Protein Kinases, catalytic domain; The protein kinase superfamily is mainly composed of the catalytic domains of serine/threonine-specific and tyrosine-specific protein kinases. It also includes RIO kinases, which are atypical serine protein kinases, aminoglycoside phosphotransferases, and choline kinases. These proteins catalyze the transfer of the gamma-phosphoryl group from ATP to hydroxyl groups in specific substrates such as serine, threonine, or tyrosine residues of proteins.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05104 233 KNCIHRDLAARNILLTHGRITKICDFGLARDIR 265

Catalytic domain of the Protein Tyrosine Kinase, Kit; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Kit is important in the development of melanocytes, germ cells, mast cells, hematopoietic stem cells, the interstitial cells of Cajal, and the pacemaker cells of the GI tract. Kit signaling is involved in major cellular functions including cell survival, proliferation, differentiation, adhesion, and chemotaxis. Mutations in Kit, which result in constitutive ligand-independent activation, are found in human cancers such as gastrointestinal stromal tumor (GIST) and testicular germ cell tumor (TGCT). The aberrant expression of Kit and/or SCF is associated with other tumor types such as systemic mastocytosis and cancers of the breast, neurons, lung, prostate, colon, and rectum. Although the structure of the human Kit catalytic domain is known, it is excluded from this specific alignment model because it contains a deletion in its sequence. Kit is a member of the Platelet Derived Growth Factor Receptor (PDGFR) subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with five immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of Kit to its ligand, the stem-cell factor (SCF), leads to receptor dimerization, trans phosphorylation and activation, and intracellular signaling. The Kit subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
                ....*....|....*....|....*....|...
gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05104 233 KNCIHRDLAARNILLTHGRITKICDFGLARDIR 265

Protein tyrosine and serine/threonine kinase; Protein phosphorylation, which plays a key role in most cellular activities, is a reversible process mediated by protein kinases and phosphoprotein phosphatases. Protein kinases catalyze the transfer of the gamma phosphate from nucleotide triphosphates (often ATP) to one or more amino acid residues in a protein substrate side chain, resulting in a conformational change affecting protein function. Phosphoprotein phosphatases catalyze the reverse process. Protein kinases fall into three broad classes, characterized with respect to substrate specificity; Serine/threonine-protein kinases, tyrosine-protein kinases, and dual specificity protein kinases (e.g. MEK - phosphorylates both Thr and Tyr on target proteins). This entry represents the catalytic domain found in a number of serine/threonine- and tyrosine-protein kinases. It does not include the catalytic domain of dual specificity kinases.

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gi 17225783    11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:pfam07714 121 KNFVHRDLAARNCLVSENLVVKISDFGLSRDI 152

cyclin-dependent protein kinase; Provisional

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gi 17225783   14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:PTZ00024 141 MHRDLSPANIFINSKGICKIADFGLAR 167

Catalytic domain of the Protein Tyrosine Kinase, Kit; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Kit is important in the development of melanocytes, germ cells, mast cells, hematopoietic stem cells, the interstitial cells of Cajal, and the pacemaker cells of the GI tract. Kit signaling is involved in major cellular functions including cell survival, proliferation, differentiation, adhesion, and chemotaxis. Mutations in Kit, which result in constitutive ligand-independent activation, are found in human cancers such as gastrointestinal stromal tumor (GIST) and testicular germ cell tumor (TGCT). The aberrant expression of Kit and/or SCF is associated with other tumor types such as systemic mastocytosis and cancers of the breast, neurons, lung, prostate, colon, and rectum. Although the structure of the human Kit catalytic domain is known, it is excluded from this specific alignment model because it contains a deletion in its sequence. Kit is a member of the Platelet Derived Growth Factor Receptor (PDGFR) subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with five immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of Kit to its ligand, the stem-cell factor (SCF), leads to receptor dimerization, trans phosphorylation and activation, and intracellular signaling. The Kit subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
                ....*....|....*....|....*....|...
gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05104 233 KNCIHRDLAARNILLTHGRITKICDFGLARDIR 265

Tyrosine kinase, catalytic domain; Phosphotransferases. Tyrosine-specific kinase subfamily.

                           10        20        30
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gi 17225783     11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:smart00219 121 KNFIHRDLAARNCLVGENLVVKISDFGLSRDL 152

Protein tyrosine and serine/threonine kinase; Protein phosphorylation, which plays a key role in most cellular activities, is a reversible process mediated by protein kinases and phosphoprotein phosphatases. Protein kinases catalyze the transfer of the gamma phosphate from nucleotide triphosphates (often ATP) to one or more amino acid residues in a protein substrate side chain, resulting in a conformational change affecting protein function. Phosphoprotein phosphatases catalyze the reverse process. Protein kinases fall into three broad classes, characterized with respect to substrate specificity; Serine/threonine-protein kinases, tyrosine-protein kinases, and dual specificity protein kinases (e.g. MEK - phosphorylates both Thr and Tyr on target proteins). This entry represents the catalytic domain found in a number of serine/threonine- and tyrosine-protein kinases. It does not include the catalytic domain of dual specificity kinases.

                          10        20        30
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gi 17225783    11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:pfam07714 121 KNFVHRDLAARNCLVSENLVVKISDFGLSRDI 152

Catalytic domain of Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. They can be classified into receptor and non-receptor tyr kinases. PTKs play important roles in many cellular processes including, lymphocyte activation, epithelium growth and maintenance, metabolism control, organogenesis regulation, survival, proliferation, differentiation, migration, adhesion, motility, and morphogenesis. Receptor tyr kinases (RTKs) are integral membrane proteins which contain an extracellular ligand-binding region, a transmembrane segment, and an intracellular tyr kinase domain. RTKs are usually activated through ligand binding, which causes dimerization and autophosphorylation of the intracellular tyr kinase catalytic domain, leading to intracellular signaling. Some RTKs are orphan receptors with no known ligands. Non-receptor (or cytoplasmic) tyr kinases are distributed in different intracellular compartments and are usually multi-domain proteins containing a catalytic tyr kinase domain as well as various regulatory domains such as SH3 and SH2. PTKs are usually autoinhibited and require a mechanism for activation. In many PTKs, the phosphorylation of tyr residues in the activation loop is essential for optimal activity. Aberrant expression of PTKs is associated with many development abnormalities and cancers.The PTK family is part of a larger superfamily that includes the catalytic domains of serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd00192 124 KKFVHRDLAARNCLVGEDLVVKISDFGLSRDI 155

Catalytic domain of the Protein Tyrosine Kinase, Platelet Derived Growth Factor Receptor alpha; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. PDGFR alpha is a receptor PTK (RTK) containing an extracellular ligand-binding region with five immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding to its ligands, the PDGFs, leads to receptor dimerization, trans phosphorylation and activation, and intracellular signaling. PDGFR alpha forms homodimers or heterodimers with PDGFR beta, depending on the nature of the PDGF ligand. PDGF-AA, PDGF-AB, and PDGF-CC induce PDGFR alpha homodimerization. PDGFR signaling plays many roles in normal embryonic development and adult physiology. PDGFR alpha signaling is important in the formation of lung alveoli, intestinal villi, mesenchymal dermis, and hair follicles, as well as in the development of oligodendrocytes, retinal astrocytes, neural crest cells, and testicular cells. Aberrant PDGFR alpha expression is associated with some human cancers. Mutations in PDGFR alpha have been found within a subset of gastrointestinal stromal tumors (GISTs). An active fusion protein FIP1L1-PDGFR alpha, derived from interstitial deletion, is associated with idiopathic hypereosinophilic syndrome and chronic eosinophilic leukemia. The PDGFR alpha subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05105 256 KNCVHRDLAARNVLLAQGKIVKICDFGLARDI 287

Catalytic domain of the Protein Tyrosine Kinases, Vascular Endothelial Growth Factor Receptors; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. VEGFR1 (or Flt1) binds VEGFA, VEGFB, and placenta growth factor (PLGF). It regulates monocyte and macrophage migration, vascular permeability, haematopoiesis, and the recruitment of haematopietic progenitor cells from the bone marrow. VEGFR1 is a member of the VEGFR subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with seven immunoglobulin (Ig)-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of VEGFRs to their ligands, the VEGFs, leads to receptor dimerization, activation, and intracellular signaling. The VEGFR1 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd14207 199 RKCIHRDLAARNILLSENNVVKICDFGLARDI 230

Catalytic domain of the Protein Tyrosine Kinase, Vascular Endothelial Growth Factor Receptor 2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. VEGFR2 (or Flk1) binds the ligands VEGFA, VEGFC, VEGFD and VEGFE. VEGFR2 signaling is implicated in all aspects of normal and pathological vascular endothelial cell biology. It induces a variety of cellular effects including migration, survival, and proliferation. It is critical in regulating embryonic vascular development and angiogenesis. VEGFR2 is the major signal transducer in pathological angiogenesis including cancer and diabetic retinopathy, and is a target for inhibition in cancer therapy. The carboxyl terminus of VEGFR2 plays an important role in its autophosphorylation and activation. VEGFR2 is a member of the VEGFR subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with seven immunoglobulin (Ig)-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of VEGFRs to their ligands, the VEGFs, leads to receptor dimerization, activation, and intracellular signaling. The VEGFR2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05103 198 RKCIHRDLAARNILLSENNVVKICDFGLARDI 229

Catalytic domain of the Protein Tyrosine Kinase, Fibroblast Growth Factor Receptor 2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. There are many splice variants of FGFR2 which show differential expression and binding to FGF ligands. Disruption of either FGFR2 or FGFR2b is lethal in mice, due to defects in the placenta or severe impairment of tissue development including lung, limb, and thyroid, respectively. Disruption of FGFR2c in mice results in defective bone and skull development. Genetic alterations of FGFR2 are associated with many human skeletal disorders including Apert syndrome, Crouzon syndrome, Jackson-Weiss syndrome, and Pfeiffer syndrome. FGFR2 is part of the FGFR subfamily, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with three immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of FGFRs to their ligands, the FGFs, results in receptor dimerization and activation, and intracellular signaling. The binding of FGFs to FGFRs is promiscuous, in that a receptor may be activated by several ligands and a ligand may bind to more that one type of receptor. The FGFR2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05101 165 QKCIHRDLAARNVLVTENNVMKIADFGLARDI 196

Catalytic domain of the Protein Tyrosine Kinases, Anaplastic Lymphoma Kinase and Leukocyte Tyrosine Kinase; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyr residues in protein substrates. ALK and LTK are orphan receptor PTKs (RTKs) whose ligands are not yet well-defined. ALK appears to play an important role in mammalian neural development as well as visceral muscle differentiation in Drosophila. ALK is aberrantly expressed as fusion proteins, due to chromosomal translocations, in about 60% of anaplastic large cell lymphomas (ALCLs). ALK fusion proteins are also found in rare cases of diffuse large B cell lymphomas (DLBCLs). LTK is mainly expressed in B lymphocytes and neuronal tissues. It is important in cell proliferation and survival. Transgenic mice expressing TLK display retarded growth and high mortality rate. In addition, a polymorphism in mouse and human LTK is implicated in the pathogenesis of systemic lupus erythematosus. RTKs contain an extracellular ligand-binding domain, a transmembrane region, and an intracellular tyr kinase domain. They are usually activated through ligand binding, which causes dimerization and autophosphorylation of the intracellular tyr kinase catalytic domain. The ALK/LTK subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTH---GRITKICDFGLARDI 42
Cdd:cd05036 138 IHRDIAARNCLLTCkgpGRVAKIGDFGMARDI 169

Catalytic domain of the Protein Tyrosine Kinase, Fibroblast Growth Factor Receptor 3; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Many FGFR3 splice variants have been reported with the IIIb and IIIc isoforms being the predominant forms. FGFR3 IIIc is the isoform expressed in chondrocytes, the cells affected in dwarfism, while IIIb is expressed in epithelial cells. FGFR3 ligands include FGF1, FGF2, FGF4, FGF8, FGF9, and FGF23. It is a negative regulator of long bone growth. In the cochlear duct and in the lens, FGFR3 is involved in differentiation while it appears to have a role in cell proliferation in epithelial cells. Germline mutations in FGFR3 are associated with skeletal disorders including several forms of dwarfism. Some missense mutations are associated with multiple myeloma and carcinomas of the bladder and cervix. Overexpression of FGFR3 is found in thyroid carcinoma. FGFR3 is part of the FGFR subfamily, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with three immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of FGFRs to their ligands, the FGFs, results in receptor dimerization and activation, and intracellular signaling. The binding of FGFs to FGFRs is promiscuous, in that a receptor may be activated by several ligands and a ligand may bind to more that one type of receptor. The FGFR3 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05100 153 QKCIHRDLAARNVLVTEDNVMKIADFGLARDV 184

Catalytic domain of the Protein Tyrosine Kinase, Fibroblast Growth Factor Receptor 4; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Unlike other FGFRs, there is only one splice form of FGFR4. It binds FGF1, FGF2, FGF6, FGF19, and FGF23. FGF19 is a selective ligand for FGFR4. Although disruption of FGFR4 in mice causes no obvious phenotype, in vivo inhibition of FGFR4 in cultured skeletal muscle cells resulted in an arrest of muscle progenitor differentiation. FGF6 and FGFR4 are uniquely expressed in myofibers and satellite cells. FGF6/FGFR4 signaling appears to play a key role in the regulation of muscle regeneration. A polymorphism in FGFR4 is found in head and neck squamous cell carcinoma. FGFR4 is part of the FGFR subfamily, which are receptor PTKs (RTKs) containing an extracellular ligand-binding region with three immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. The binding of FGFRs to their ligands, the FGFs, results in receptor dimerization and activation, and intracellular signaling. The binding of FGFs to FGFRs is promiscuous, in that a receptor may be activated by several ligands and a ligand may bind to more that one type of receptor. The FGFR4 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05099 153 RRCIHRDLAARNVLVTEDNVMKIADFGLARGV 184

Catalytic domain of the Protein Tyrosine Kinase, REarranged during Transfection protein; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. RET is a receptor PTK (RTK) containing an extracellular region with four cadherin-like repeats, a calcium-binding site, and a cysteine-rich domain, a transmembrane segment, and an intracellular catalytic domain. It is part of a multisubunit complex that binds glial-derived neurotropic factor (GDNF) family ligands (GFLs) including GDNF, neurturin, artemin, and persephin. GFLs bind RET along with four GPI-anchored coreceptors, bringing two RET molecules together, leading to autophosphorylation, activation, and intracellular signaling. RET is essential for the development of the sympathetic, parasympathetic and enteric nervous systems, and the kidney. RET disruption by germline mutations causes diseases in humans including congenital aganglionosis of the gastrointestinal tract (Hirschsprung's disease) and three related inherited cancers: multiple endocrine neoplasia type 2A (MEN2A), MEN2B, and familial medullary thyroid carcinoma. The RET subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05045 149 VHRDLAARNVLVAEGRKMKISDFGLSRDV 177

Catalytic domain of the Protein Tyrosine Kinase, C-ros; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. This subfamily contains c-ros, Sevenless, and similar proteins. The proto-oncogene c-ros encodes an orphan receptor PTK (RTK) with an unknown ligand. RTKs contain an extracellular ligand-binding domain, a transmembrane region, and an intracellular tyr kinase domain. RTKs are usually activated through ligand binding, which causes dimerization and autophosphorylation of the intracellular tyr kinase catalytic domain. C-ros is expressed in embryonic cells of the kidney, intestine and lung, but disappears soon after birth. It persists only in the adult epididymis. Male mice bearing inactive mutations of c-ros lack the initial segment of the epididymis and are infertile. The Drosophila protein, Sevenless, is required for the specification of the R7 photoreceptor cell during eye development. The c-ros subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLT----HGRITKICDFGLARDI 42
Cdd:cd05044 128 VHRDLAARNCLVSskdyRERVVKIGDFGLARDI 160

Catalytic domain of C-terminal Src kinase-like Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. This subfamily is composed of Csk, Chk, and similar proteins. They are cytoplasmic (or nonreceptor) PTKs containing the Src homology domains, SH3 and SH2, N-terminal to the catalytic tyr kinase domain. They negatively regulate the activity of Src kinases that are anchored to the plasma membrane. To inhibit Src kinases, Csk and Chk are translocated to the membrane via binding to specific transmembrane proteins, G-proteins, or adaptor proteins near the membrane. Csk catalyzes the tyr phosphorylation of the regulatory C-terminal tail of Src kinases, resulting in their inactivation. Chk inhibit Src kinases using a noncatalytic mechanism by simply binding to them. As negative regulators of Src kinases, Csk and Chk play important roles in cell proliferation, survival, and differentiation, and consequently, in cancer development and progression. The Csk-like subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARD 41
Cdd:cd05039 121 KKFVHRDLAARNVLVSEDNVAKVSDFGLAKE 151

Catalytic domain of the Protein Tyrosine Kinases, Src-related kinase lacking C-terminal regulatory tyrosine and N-terminal myristylation sites (Srm) and Breast tumor kinase (Brk); PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Srm and Brk (also called protein tyrosine kinase 6) are members of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Brk has been found to be overexpressed in a majority of breast tumors. Src kinases in general contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr; they are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). Srm and Brk however, lack the N-terminal myristylation sites. Src proteins are involved in signaling pathways that regulate cytokine and growth factor responses, cytoskeleton dynamics, cell proliferation, survival, and differentiation. The Srm/Brk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05148 123 QNSIHRDLAARNILVGEDLVCKVADFGLARLIK 155

Catalytic domain of Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine or tyrosine residues on protein substrates. PKs make up a large family of serine/threonine kinases (STKs), protein tyrosine kinases (PTKs), and dual-specificity PKs that phosphorylate both serine/threonine and tyrosine residues of target proteins. Majority of protein phosphorylation occurs on serine residues while only 1% occurs on tyrosine residues. Protein phosphorylation is a mechanism by which a wide variety of cellular proteins, such as enzymes and membrane channels, are reversibly regulated in response to certain stimuli. PKs often function as components of signal transduction pathways in which one kinase activates a second kinase, which in turn, may act on other kinases; this sequential action transmits a signal from the cell surface to target proteins, which results in cellular responses. The PK family is one of the largest known protein families with more than 100 homologous yeast enzymes and more than 500 human proteins. A fraction of PK family members are pseudokinases that lack crucial residues for catalytic activity. The mutiplicity of kinases allows for specific regulation according to substrate, tissue distribution, and cellular localization. PKs regulate many cellular processes including proliferation, division, differentiation, motility, survival, metabolism, cell-cycle progression, cytoskeletal rearrangement, immunity, and neuronal functions. Many kinases are implicated in the development of various human diseases including different types of cancer. The PK family is part of a larger superfamily that includes the catalytic domains of RIO kinases, aminoglycoside phosphotransferase, choline kinase, phosphoinositide 3-kinase (PI3K), and actin-fragmin kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd00180 111 NGIIHRDLKPENILLDSDGTVKLADFGLAKDL 142

Catalytic domain of Male germ cell-Associated Kinase-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of human MAK and MAK-related kinase (MRK), Saccharomyces cerevisiae Ime2p, Schizosaccharomyces pombe Mei4-dependent protein 3 (Mde3) and Pit1, Caenorhabditis elegans dyf-5, Arabidopsis thaliana MHK, and similar proteins. These proteins play important roles during meiosis. MAK is highly expressed in testicular cells specifically in the meiotic phase, but is not essential for spermatogenesis and fertility. It functions as a coactivator of the androgen receptor in prostate cells. MRK, also called Intestinal Cell Kinase (ICK), is expressed ubiquitously, with highest expression in the ovary and uterus. A missense mutation in MRK causes endocrine-cerebro-osteodysplasia, suggesting that this protein plays an important role in the development of many organs. MAK and MRK may be involved in regulating cell cycle and cell fate. Ime2p is a meiosis-specific kinase that is important during meiotic initiation and during the later stages of meiosis. Mde3 functions downstream of the transcription factor Mei-4 which is essential for meiotic prophase I. The MAK-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  15 HRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd07830 122 HRDLKPENLLVSGPEVVKIADFGLAREIR 150

Catalytic domain of Spleen Tyrosine Kinase-like Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The Syk-like subfamily is composed of Syk, ZAP-70, Shark, and similar proteins. They are cytoplasmic (or nonreceptor) PTKs containing two Src homology 2 (SH2) domains N-terminal to the catalytic tyr kinase domain. They are involved in the signaling downstream of activated receptors (including B-cell, T-cell, and Fc receptors) that contain ITAMs (immunoreceptor tyr activation motifs), leading to processes such as cell proliferation, differentiation, survival, adhesion, migration, and phagocytosis. Syk is important in B-cell receptor signaling, while Zap-70 is primarily expressed in T-cells and NK cells, and is a crucial component in T-cell receptor signaling. Syk also plays a central role in Fc receptor-mediated phagocytosis in the adaptive immune system. Shark is exclusively expressed in ectodermally derived epithelia, and is localized preferentially to the apical surface of the epithelial cells, it may play a role in a signaling pathway for epithelial cell polarity. The Syk-like subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05060 117 VHRDLAARNVLLVNRHQAKISDFGMSRALG 146

Serine/Threonine protein kinases, catalytic domain; Phosphotransferases. Serine or threonine-specific kinase subfamily.

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gi 17225783     11 QQCIHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:smart00220 116 KGIVHRDLKPENILLDEDGHVKLADFGLARQLD 148

Catalytic domain of the Protein Tyrosine Kinase, Fes; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Fes (or Fps) is a cytoplasmic (or nonreceptor) PTK containing an N-terminal region with FCH (Fes/Fer/CIP4 homology) and coiled-coil domains, followed by a SH2 domain, and a C-terminal catalytic domain. The genes for Fes (feline sarcoma) and Fps (Fujinami poultry sarcoma) were first isolated from tumor-causing retroviruses. The viral oncogenes encode chimeric Fes proteins consisting of Gag sequences at the N-termini, resulting in unregulated PTK activity. Fes kinase is expressed in myeloid, vascular endothelial, epithelial, and neuronal cells. It plays important roles in cell growth and differentiation, angiogenesis, inflammation and immunity, and cytoskeletal regulation. A recent study implicates Fes kinase as a tumor suppressor in colorectal cancer. The Fes subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARD 41
Cdd:cd05084 114 KHCIHRDLAARNCLVTEKNVLKISDFGMSRE 144

Catalytic (repeat 2) domain of the Protein Tyrosine Kinase, Tyrosine kinase 2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Tyk2 is widely expressed in many tissues. It is involved in signaling via the cytokine receptors IFN-alphabeta, IL-6, IL-10, IL-12, IL-13, and IL-23. It mediates cell surface urokinase receptor (uPAR) signaling and plays a role in modulating vascular smooth muscle cell (VSMC) functional behavior in response to injury. Tyk2 is also important in dendritic cell function and T helper (Th)1 cell differentiation. A homozygous mutation of Tyk2 was found in a patient with hyper-IgE syndrome (HIES), a primary immunodeficiency characterized by recurrent skin abscesses, pneumonia, and elevated serum IgE. This suggests that Tyk2 may play important roles in multiple cytokine signaling involved in innate and adaptive immunity. Tyk2 is a member of the Janus kinase (Jak) subfamily of proteins, which are cytoplasmic (or nonreceptor) PTKs containing an N-terminal FERM domain, followed by a Src homology 2 (SH2) domain, a pseudokinase domain, and a C-terminal tyr kinase catalytic domain. Jaks are crucial for cytokine receptor signaling. They are activated by autophosphorylation upon cytokine-induced receptor aggregation, and subsequently trigger downstream signaling events such as the phosphorylation of signal transducers and activators of transcription (STATs). The Tyk2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05080 126 QHYIHRDLAARNVLLDNDRLVKIGDFGLAKAV 157

Catalytic domain of Ephrin Receptor Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. EphRs comprise the largest subfamily of receptor PTKs (RTKs). They can be classified into two classes (EphA and EphB), according to their extracellular sequences, which largely correspond to binding preferences for either GPI-anchored ephrin-A ligands or transmembrane ephrin-B ligands. Vertebrates have ten EphA and six EphB receptors, which display promiscuous ligand interactions within each class. EphRs contain an ephrin binding domain and two fibronectin repeats extracellularly, a transmembrane segment, and a cytoplasmic tyr kinase domain. Binding of the ephrin ligand to EphR requires cell-cell contact since both are anchored to the plasma membrane. This allows ephrin/EphR dimers to form, leading to the activation of the intracellular tyr kinase domain. The resulting downstream signals occur bidirectionally in both EphR-expressing cells (forward signaling) and ephrin-expressing cells (reverse signaling). The main effect of ephrin/EphR interaction is cell-cell repulsion or adhesion. Ephrin/EphR signaling is important in neural development and plasticity, cell morphogenesis and proliferation, cell-fate determination, embryonic development, tissue patterning, and angiogenesis.The EphR subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05033 128 VHRDLAARNILVNSDLVCKVSDFGLSRRLE 157

Catalytic domain of Cyclin-Dependent protein Kinase Like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of CDKL1-5 and similar proteins. Some CDKLs, like CDKL1 and CDKL3, may be implicated in transformation and others, like CDKL3 and CDKL5, are associated with mental retardation when impaired. CDKL2 plays a role in learning and memory. CDKs belong to a large family of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. The CDKL subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  12 QCIHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd07833 120 NIIHRDIKPENILVSESGVLKLCDFGFARALT 151

Catalytic domain of AMP-activated protein kinase-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The AMPK-like subfamily is composed of AMPK, MARK, BRSK, NUAK, MELK, SNRK, TSSK, and SIK, among others. LKB1 serves as a master upstream kinase that activates AMPK and most AMPK-like kinases. AMPK, also called SNF1 (sucrose non-fermenting1) in yeasts and SnRK1 (SNF1-related kinase1) in plants, is a heterotrimeric enzyme composed of a catalytic alpha subunit and two regulatory subunits, beta and gamma. It is a stress-activated kinase that serves as master regulator of glucose and lipid metabolism by monitoring carbon and energy supplies, via sensing the cell's AMP:ATP ratio. MARKs phosphorylate tau and related microtubule-associated proteins (MAPs), and regulates microtubule-based intracellular transport. They are involved in embryogenesis, epithelial cell polarization, cell signaling, and neuronal differentiation. BRSKs play important roles in establishing neuronal polarity. TSSK proteins are almost exclusively expressed postmeiotically in the testis and play important roles in spermatogenesis and/or spermiogenesis. The AMPK-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILL-THGRItKICDFGLARDIR 43
Cdd:cd14003 118 NGIVHRDLKLENILLdKNGNL-KIIDFGLSNEFR 150

Catalytic domain of the Protein Tyrosine Kinase, Abelson kinase; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Abl (or c-Abl) is a ubiquitously-expressed cytoplasmic (or nonreceptor) PTK that contains SH3, SH2, and tyr kinase domains in its N-terminal region, as well as nuclear localization motifs, a putative DNA-binding domain, and F- and G-actin binding domains in its C-terminal tail. It also contains a short autoinhibitory cap region in its N-terminus. Abl function depends on its subcellular localization. In the cytoplasm, Abl plays a role in cell proliferation and survival. In response to DNA damage or oxidative stress, Abl is transported to the nucleus where it induces apoptosis. In chronic myelogenous leukemia (CML) patients, an aberrant translocation results in the replacement of the first exon of Abl with the BCR (breakpoint cluster region) gene. The resulting BCR-Abl fusion protein is constitutively active and associates into tetramers, resulting in a hyperactive kinase sending a continuous signal. This leads to uncontrolled proliferation, morphological transformation and anti-apoptotic effects. BCR-Abl is the target of selective inhibitors, such as imatinib (Gleevec), used in the treatment of CML. Abl2, also known as ARG (Abelson-related gene), is thought to play a cooperative role with Abl in the proper development of the nervous system. The Tel-ARG fusion protein, resulting from reciprocal translocation between chromosomes 1 and 12, is associated with acute myeloid leukemia (AML). The TEL gene is a frequent fusion partner of other tyr kinase oncogenes, including Tel/Abl, Tel/PDGFRbeta, and Tel/Jak2, found in patients with leukemia and myeloproliferative disorders. The Abl subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05052 126 IHRDLAARNCLVGENHLVKVADFGLSRLMT 155

Catalytic domain of the Protein Tyrosine Kinase, Fer; Protein Tyrosine Kinase (PTK) family; Fer kinase; catalytic (c) domain. The PTKc family is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, and phosphoinositide 3-kinase (PI3K). PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Fer kinase is a member of the Fes subfamily of proteins which are cytoplasmic (or nonreceptor) tyr kinases containing an N-terminal region with FCH (Fes/Fer/CIP4 homology) and coiled-coil domains, followed by a SH2 domain, and a C-terminal catalytic domain. Fer kinase is expressed in a wide variety of tissues, and is found to reside in both the cytoplasm and the nucleus. It plays important roles in neuronal polarization and neurite development, cytoskeletal reorganization, cell migration, growth factor signaling, and the regulation of cell-cell interactions mediated by adherens junctions and focal adhesions. Fer kinase also regulates cell cycle progression in malignant cells.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05085 113 KNCIHRDLAARNCLVGENNALKISDFGMSR 142

Catalytic domain of Numb-Associated Kinase (NAK)-like Serine/Threonine kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of Drosophila melanogaster NAK, human BMP-2-inducible protein kinase (BMP2K or BIKe) and similar vertebrate proteins, as well as the Saccharomyces cerevisiae proteins Prk1, Actin-regulating kinase 1 (Ark1), and Akl1. NAK was the first characterized member of this subfamily. It plays a role in asymmetric cell division through its association with Numb. It also regulates the localization of Dlg, a protein essential for septate junction formation. BMP2K contains a nuclear localization signal and a kinase domain that is capable of phosphorylating itself and myelin basic protein. The expression of the BMP2K gene is increase during BMP-2-induced osteoblast differentiation. It may function to control the rate of differentiation. Prk1, Ark1, and Akl1 comprise a subfamily of yeast proteins that are important regulators of the actin cytoskeleton and endocytosis. They share an N-terminal kinase domain but no significant homology in other regions of their sequences. The NAK-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783   2 AVAVFPFLPQQCIHRDLAARNILLTHGRITKICDFGLA 39
Cdd:cd14037 120 AVAAMHYLKPPLIHRDLKVENVLISDSGNYKLCDFGSA 157

Catalytic domain of the Protein Tyrosine Kinase, Csk homologous kinase; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Chk is also referred to as megakaryocyte-associated tyrosine kinase (Matk). Chk inhibits Src kinases using a noncatalytic mechanism by simply binding to them. As a negative regulator of Src kinases, Chk may play important roles in cell proliferation, survival, and differentiation, and consequently, in cancer development and progression. Chk is expressed in brain and hematopoietic cells. Like Csk, it is a cytoplasmic (or nonreceptor) tyr kinase containing the Src homology domains, SH3 and SH2, N-terminal to the catalytic tyr kinase domain. To inhibit Src kinases that are anchored to the plasma membrane, Chk is translocated to the membrane via binding to specific transmembrane proteins, G-proteins, or adaptor proteins near the membrane. Studies in mice reveal that Chk is not functionally redundant with Csk and that it plays an important role as a regulator of immune responses. Chk also plays a role in neural differentiation in a manner independent of Src by enhancing Mapk activation via Ras-mediated signaling. The Chk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05083 122 VHRDLAARNILVSEDGVAKISDFGLAK 148

Catalytic domain of Tie Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Tie proteins, consisting of Tie1 and Tie2, are receptor PTKs (RTKs) containing an extracellular region, a transmembrane segment, and an intracellular catalytic domain. The extracellular region contains an immunoglobulin (Ig)-like domain, three epidermal growth factor (EGF)-like domains, a second Ig-like domain, and three fibronectin type III repeats. Tie receptors are specifically expressed in endothelial cells and hematopoietic stem cells. The angiopoietins (Ang-1 to Ang-4) serve as ligands for Tie2, while no specific ligand has been identified for Tie1. The binding of Ang-1 to Tie2 leads to receptor autophosphorylation and activation, promoting cell migration and survival. In contrast, Ang-2 binding to Tie2 does not result in the same response, suggesting that Ang-2 may function as an antagonist. In vivo studies of Tie1 show that it is critical in vascular development. The Tie subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05047 131 KQFIHRDLAARNILVGENYVAKIADFGLSR 160

Catalytic domain of the Protein Tyrosine Kinase, Interleukin-2-inducible T-cell Kinase; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Itk, also known as Tsk or Emt, is a member of the Tec-like subfamily of proteins, which are cytoplasmic (or nonreceptor) PTKs with similarity to Src kinases in that they contain Src homology protein interaction domains (SH3, SH2) N-terminal to the catalytic tyr kinase domain. Unlike Src kinases, most Tec subfamily members except Rlk also contain an N-terminal pleckstrin homology (PH) domain, which binds the products of PI3K and allows membrane recruitment and activation. In addition, Itk contains the Tec homology (TH) domain containing one proline-rich region and a zinc-binding region. Itk is expressed in T-cells and mast cells, and is important in their development and differentiation. Of the three Tec kinases expressed in T-cells, Itk plays the predominant role in T-cell receptor (TCR) signaling. It is activated by phosphorylation upon TCR crosslinking and is involved in the pathway resulting in phospholipase C-gamma1 activation and actin polymerization. It also plays a role in the downstream signaling of the T-cell costimulatory receptor CD28, the T-cell surface receptor CD2, and the chemokine receptor CXCR4. In addition, Itk is crucial for the development of T-helper(Th)2 effector responses. The Itk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783   8 FLPQQC-IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05112 115 YLEEASvIHRDLAARNCLVGENQVVKVSDFGMTR 148

Catalytic domain of the Serine/Threonine Kinase, Never In Mitosis gene A (NIMA)-related kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The Nek family is composed of 11 different mammalian members (Nek1-11) with similarity to the catalytic domain of Aspergillus nidulans NIMA kinase, the founding member of the Nek family, which was identified in a screen for cell cycle mutants that were prevented from entering mitosis. Neks contain a conserved N-terminal catalytic domain and a more divergent C-terminal regulatory region of various sizes and structures. They are involved in the regulation of downstream processes following the activation of Cdc2, and many of their functions are cell cycle-related. They play critical roles in microtubule dynamics during ciliogenesis and mitosis. The Nek family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd08215 125 LHRDLKTQNIFLTKDGVVKLGDFGISK 151

Catalytic domain of the Protein Tyrosine Kinases, Tropomyosin Related Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The Trk subfamily consists of TrkA, TrkB, TrkC, and similar proteins. They are receptor PTKs (RTKs) containing an extracellular region with arrays of leucine-rich motifs flanked by two cysteine-rich clusters followed by two immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. Binding to their ligands, the nerve growth factor (NGF) family of neutrotrophins, leads to Trk receptor oligomerization and activation of the catalytic domain. Trk receptors are mainly expressed in the peripheral and central nervous systems. They play important roles in cell fate determination, neuronal survival and differentiation, as well as in the regulation of synaptic plasticity. Altered expression of Trk receptors is associated with many human diseases. The Trk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05049 141 QHFVHRDLATRNCLVGTNLVVKIGDFGMSRDI 172

Catalytic domain of Cyclin-Dependent protein Kinase 9-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of CDK9 and CDK12 from higher eukaryotes, yeast BUR1, C-type plant CDKs (CdkC), and similar proteins. CDK9, BUR1, and CdkC are functionally equivalent. They act as a kinase for the C-terminal domain of RNA polymerase II and participate in regulating mutliple steps of gene expression including transcription elongation and RNA processing. CDK9 and CdkC associate with T-type cyclins while BUR1 associates with the cyclin BUR2. CDK12 is a unique CDK that contains an arginine/serine-rich (RS) domain, which is predominantly found in splicing factors. CDK12 interacts with cyclins L1 and L2, and participates in regulating transcription and alternative splicing. CDKs belong to a large family of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. The CDK9-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd07840 126 LHRDIKGSNILINNDGVLKLADFGLAR 152

Catalytic domain of STE family Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine (ST) or tyrosine residues on protein substrates. This family is composed of STKs, and some dual-specificity PKs that phosphorylate both threonine and tyrosine residues of target proteins. Most members are kinases involved in mitogen-activated protein kinase (MAPK) signaling cascades, acting as MAPK kinases (MAPKKs), MAPKK kinases (MAPKKKs), or MAPKKK kinases (MAP4Ks). The MAPK signaling pathways are important mediators of cellular responses to extracellular signals. The pathways involve a triple kinase core cascade comprising of the MAPK, which is phosphorylated and activated by a MAPKK, which itself is phosphorylated and activated by a MAPKKK. Each MAPK cascade is activated either by a small GTP-binding protein or by an adaptor protein, which transmits the signal either directly to a MAPKKK to start the triple kinase core cascade or indirectly through a mediator kinase, a MAP4K. Other STE family members include p21-activated kinases (PAKs) and class III myosins, among others. PAKs are Rho family GTPase-regulated kinases that serve as important mediators in the function of Cdc42 (cell division cycle 42) and Rac. Class III myosins are motor proteins containing an N-terminal kinase catalytic domain and a C-terminal actin-binding domain, which can phosphorylate several cytoskeletal proteins, conventional myosin regulatory light chains, as well as autophosphorylate the C-terminal motor domain. They play an important role in maintaining the structural integrity of photoreceptor cell microvilli. The STE family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTH-GRItKICDFGLARDI 42
Cdd:cd05122 117 HGIIHRDIKAANILLTSdGEV-KLIDFGLSAQL 148

Catalytic domain of the Serine/Threonine Kinase, Cyclin-Dependent protein Kinase 4; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CDK4 partners with all three D-type cyclins (D1, D2, and D3) and is also regulated by INK4 inhibitors. It is active towards the retinoblastoma (pRb) protein and plays a role in regulating the early G1 phase of the cell cycle. It is expressed ubiquitously and is localized in the nucleus. CDK4 also shows kinase activity towards Smad3, a signal transducer of TGF-beta signaling which modulates transcription and plays a role in cell proliferation and apoptosis. CDK4 is inhibited by the p21 inhibitor and is specifically mutated in human melanoma. CDKs belong to a large family of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. The CDK4 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783   8 FLPQQCI-HRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd07863 123 FLHANCIvHRDLKPENILVTSGGQVKLADFGLAR 156

Catalytic domain of a subset of Src kinase-like Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. This subfamily includes a subset of Src-like PTKs including Src, Fyn, Yrk, and Yes, which are all widely expressed. Yrk has been detected only in chickens. It is primarily found in neuronal and epithelial cells and in macrophages. It may play a role in inflammation and in response to injury. Src (or c-Src) proteins are cytoplasmic (or non-receptor) PTKs which are anchored to the plasma membrane. They contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). Src proteins are involved in signaling pathways that regulate cytokine and growth factor responses, cytoskeleton dynamics, cell proliferation, survival, and differentiation. They were identified as the first proto-oncogene products, and they regulate cell adhesion, invasion, and motility in cancer cells and tumor vasculature, contributing to cancer progression and metastasis. They are also implicated in acute inflammatory responses and osteoclast function. The Src/Fyn-like subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd14203 113 IHRDLRAANILVGDNLVCKIADFGLARLIE 142

Catalytic domain of the Serine/Threonine Kinase, Mixed lineage kinase-Like mitogen-activated protein Triple Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MLTK, also called zipper sterile-alpha-motif kinase (ZAK), contains a catalytic kinase domain and a leucine zipper. There are two alternatively-spliced variants, MLTK-alpha and MLTK-beta. MLTK-alpha contains a sterile-alpha-motif (SAM) at the C-terminus. MLTK regulates the c-Jun N-terminal kinase, extracellular signal-regulated kinase, p38 MAPK, and NF-kB pathways. ZAK is the MAP3K involved in the signaling cascade that leads to the ribotoxic stress response initiated by cellular damage due to Shiga toxins and ricin. It may also play a role in cell transformation and cancer development. MAP3Ks (MKKKs or MAPKKKs) phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals.The MLTK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  10 PQQCIHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd14060 105 PVKVIHRDLKSRNVVIAADGVLKICDFGASR 135

Catalytic domain of the Protein Tyrosine Kinase, Muscle-specific kinase; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Musk is a receptor PTK (RTK) containing an extracellular region with four immunoglobulin-like domains and a cysteine-rich cluster, a transmembrane segment, and an intracellular catalytic domain. Musk is expressed and concentrated in the postsynaptic membrane in skeletal muscle. It is essential for the establishment of the neuromuscular junction (NMJ), a peripheral synapse that conveys signals from motor neurons to muscle cells. Agrin, a large proteoglycan released from motor neurons, stimulates Musk autophosphorylation and activation, leading to the clustering of acetylcholine receptors (AChRs). To date, there is no evidence to suggest that agrin binds directly to Musk. Mutations in AChR, Musk and other partners are responsible for diseases of the NMJ, such as the autoimmune syndrome myasthenia gravis. The Musk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05050 152 VHRDLATRNCLVGENMVVKIADFGLSRNI 180

Catalytic domain of the Protein Tyrosine Kinases, Lymphocyte-specific kinase and Blk; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Lck and Blk are members of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Lck is expressed in T-cells and natural killer cells. It plays a critical role in T-cell maturation, activation, and T-cell receptor (TCR) signaling. Lck phosphorylates ITAM (immunoreceptor tyr activation motif) sequences on several subunits of TCRs, leading to the activation of different second messenger cascades. Phosphorylated ITAMs serve as binding sites for other signaling factor such as Syk and ZAP-70, leading to their activation and propagation of downstream events. In addition, Lck regulates drug-induced apoptosis by interfering with the mitochondrial death pathway. The apototic role of Lck is independent of its primary function in T-cell signaling. Blk is expressed specifically in B-cells. It is involved in pre-BCR (B-cell receptor) signaling. Src kinases contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). The Lck/Blk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05067 125 IHRDLRAANILVSDTLSCKIADFGLARLI 153

Catalytic domain of the Protein Tyrosine Kinase, Spleen tyrosine kinase; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Syk is a cytoplasmic (or nonreceptor) PTK containing two Src homology 2 (SH2) domains N-terminal to the catalytic tyr kinase domain. Syk was first cloned from the spleen, and its function in hematopoietic cells is well-established. It is involved in the signaling downstream of activated receptors (including B-cell and Fc receptors) that contain ITAMs (immunoreceptor tyr activation motifs), leading to processes such as cell proliferation, differentiation, survival, adhesion, migration, and phagocytosis. More recently, Syk expression has been detected in other cell types (including epithelial cells, vascular endothelial cells, neurons, hepatocytes, and melanocytes), suggesting a variety of biological functions in non-immune cells. Syk plays a critical role in maintaining vascular integrity and in wound healing during embryogenesis. It also regulates Vav3, which is important in osteoclast function including bone development. In breast epithelial cells, where Syk acts as a negative regulator for EGFR signaling, loss of Syk expression is associated with abnormal proliferation during cancer development suggesting a potential role as a tumor suppressor. In mice, Syk has been shown to inhibit malignant transformation of mammary epithelial cells induced with murine mammary tumor virus (MMTV). The Syk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd05116 117 VHRDLAARNVLLVTQHYAKISDFGLSKALR 146

Catalytic domain of the Protein Tyrosine Kinase, Zeta-chain-associated protein of 70kDa; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Zap-70 is a cytoplasmic (or nonreceptor) PTK containing two Src homology 2 (SH2) domains N-terminal to the catalytic tyr kinase domain. Zap-70 is primarily expressed in T-cells and NK cells, and is a crucial component in T-cell receptor (TCR) signaling. Zap-70 binds the phosphorylated ITAM (immunoreceptor tyr activation motif) sequences of the activated TCR zeta-chain through its SH2 domains, leading to its phosphorylation and activation. It then phosphorylates target proteins, which propagate the signals to downstream pathways. Zap-70 is hardly detected in normal peripheral B-cells, but is present in some B-cell malignancies. It is used as a diagnostic marker for chronic lymphocytic leukemia (CLL) as it is associated with the more aggressive subtype of the disease. The Zap-70 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
                ....*....|....*....|....*..
gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05115 126 VHRDLAARNVLLVNQHYAKISDFGLSK 152

Catalytic domain of the Protein Tyrosine Kinase, Ephrin Receptor A2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The EphA2 receptor is overexpressed in tumor cells and tumor blood vessels in a variety of cancers including breast, prostate, lung, and colon. As a result, it is an attractive target for drug design since its inhibition could affect several aspects of tumor progression. EphRs comprise the largest subfamily of receptor PTKs (RTKs). Class EphA receptors bind GPI-anchored ephrin-A ligands. There are ten vertebrate EphA receptors (EphA1-10), which display promiscuous interactions with six ephrin-A ligands. EphRs contain an ephrin binding domain and two fibronectin repeats extracellularly, a transmembrane segment, and a cytoplasmic tyr kinase domain. Binding of the ephrin ligand to EphR requires cell-cell contact since both are anchored to the plasma membrane. The resulting downstream signals occur bidirectionally in both EphR-expressing cells (forward signaling) and ephrin-expressing cells (reverse signaling). Ephrin/EphR interaction mainly results in cell-cell repulsion or adhesion, making it important in neural development and plasticity, cell morphogenesis, cell-fate determination, embryonic development, tissue patterning, and angiogenesis. The EphA2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, and phosphoinositide 3-kinase (PI3K).

                        10        20
                ....*....|....*....|....*..
gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05063 129 VHRDLAARNILVNSNLECKVSDFGLSR 155

Catalytic domain of the Protein Tyrosine Kinases, Bruton's tyrosine kinase and Bone marrow kinase on the X chromosome; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Btk and Bmx (also named Etk) are members of the Tec-like subfamily of proteins, which are cytoplasmic (or nonreceptor) PTKs with similarity to Src kinases in that they contain Src homology protein interaction domains (SH3, SH2) N-terminal to the catalytic tyr kinase domain. Unlike Src kinases, most Tec subfamily members except Rlk also contain an N-terminal pleckstrin homology (PH) domain, which binds the products of PI3K and allows membrane recruitment and activation. In addition, Btk contains the Tec homology (TH) domain with proline-rich and zinc-binding regions. Btk is expressed in B-cells, and a variety of myeloid cells including mast cells, platelets, neutrophils, and dendrictic cells. It interacts with a variety of partners, from cytosolic proteins to nuclear transcription factors, suggesting a diversity of functions. Stimulation of a diverse array of cell surface receptors, including antigen engagement of the B-cell receptor, leads to PH-mediated membrane translocation of Btk and subsequent phosphorylation by Src kinase and activation. Btk plays an important role in the life cycle of B-cells including their development, differentiation, proliferation, survival, and apoptosis. Mutations in Btk cause the primary immunodeficiency disease, X-linked agammaglobulinaemia (XLA) in humans. Bmx is primarily expressed in bone marrow and the arterial endothelium, and plays an important role in ischemia-induced angiogenesis. It facilitates arterial growth, capillary formation, vessel maturation, and bone marrow-derived endothelial progenitor cell mobilization. The Btk/Bmx subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05113 119 KQFLHRDLAARNCLVNDQGVVKVSDFGLSR 148

Catalytic domain of the Protein Tyrosine Kinase, HER2; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. HER2 (ErbB2, HER2/neu) is a member of the EGFR (HER, ErbB) subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular EGF-related ligand-binding region, a transmembrane helix, and a cytoplasmic region with a tyr kinase domain and a regulatory C-terminal tail. Unlike other PTKs, phosphorylation of the activation loop of EGFR proteins is not critical to their activation. Instead, they are activated by ligand-induced dimerization, leading to the phosphorylation of tyr residues in the C-terminal tail, which serve as binding sites for downstream signaling molecules. HER2 does not bind to any known EGFR subfamily ligands, but contributes to the kinase activity of all possible heterodimers. It acts as the preferred partner of other ligand-bound EGFR proteins and functions as a signal amplifier, with the HER2-HER3 heterodimer being the most potent pair in mitogenic signaling. HER2 plays an important role in cell development, proliferation, survival and motility. Overexpression of HER2 results in its activation and downstream signaling, even in the absence of ligand. HER2 overexpression, mainly due to gene amplification, has been shown in a variety of human cancers. Its role in breast cancer is especially well-documented. HER2 is up-regulated in about 25% of breast tumors and is associated with increases in tumor aggressiveness, recurrence and mortality. HER2 is a target for monoclonal antibodies and small molecule inhibitors, which are being developed as treatments for cancer. The first humanized antibody approved for clinical use is Trastuzumab (Herceptin), which is being used in combination with other therapies to improve the survival rates of patients with HER2-overexpressing breast cancer. The HER2 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
                ....*....|....*....|....*..
gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05109 131 VHRDLAARNVLVKSPNHVKITDFGLAR 157

Catalytic domain of the Serine/Threonine kinase, Interleukin-1 Receptor Associated Kinase 4; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. IRAKs are involved in Toll-like receptor (TLR) and interleukin-1 (IL-1) signalling pathways, and are thus critical in regulating innate immune responses and inflammation. IRAKs contain an N-terminal Death domain (DD), a proST region (rich in serines, prolines, and threonines), a central kinase domain, and a C-terminal domain; IRAK-4 lacks the C-terminal domain. Vertebrates contain four IRAKs (IRAK-1, -2, -3 (or -M), and -4) that display distinct functions and patterns of expression and subcellular distribution, and can differentially mediate TLR signaling. IRAK4 plays a critical role in NFkB activation by its interaction with MyD88, which acts as a scaffold that enables IRAK4 to phosphorylate and activate IRAK1 and/or IRAK2. It also plays an important role in type I IFN production induced by TLR7/8/9. The IRAK4 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
                ....*....|....*....|....*..
gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd14158 139 IHRDIKSANILLDETFVPKISDFGLAR 165

Catalytic domain of Extracellular signal-Regulated Kinase 1 and 2-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of the mitogen-activated protein kinases (MAPKs) ERK1, ERK2, baker's yeast Fus3, and similar proteins. MAPK pathways are important mediators of cellular responses to extracellular signals. ERK1/2 activation is preferentially by mitogenic factors, differentiation stimuli, and cytokines, through a kinase cascade involving the MAPK kinases MEK1/2 and a MAPK kinase kinase from the Raf family. ERK1/2 have numerous substrates, many of which are nuclear and participate in transcriptional regulation of many cellular processes. They regulate cell growth, cell proliferation, and cell cycle progression from G1 to S phase. Although the distinct roles of ERK1 and ERK2 have not been fully determined, it is known that ERK2 can maintain most functions in the absence of ERK1, and that the deletion of ERK2 is embryonically lethal. The MAPK, Fus3, regulates yeast mating processes including mating-specific gene expression, G1 arrest, mating projection, and cell fusion. This ERK1/2-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd07849 128 LHRDLKPSNLLLNTNCDLKICDFGLAR 154

Catalytic domain of the Protein Tyrosine Kinase, Epidermal Growth Factor Receptor; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. EGFR (HER1, ErbB1) is a receptor PTK (RTK) containing an extracellular EGF-related ligand-binding region, a transmembrane helix, and a cytoplasmic region with a tyr kinase domain and a regulatory C-terminal tail. Unlike other PTKs, phosphorylation of the activation loop of EGFR proteins is not critical to their activation. Instead, they are activated by ligand-induced dimerization, leading to the phosphorylation of tyr residues in the C-terminal tail, which serve as binding sites for downstream signaling molecules. Ligands for EGFR include EGF, heparin binding EGF-like growth factor (HBEGF), epiregulin, amphiregulin, TGFalpha, and betacellulin. Upon ligand binding, EGFR can form homo- or heterodimers with other EGFR subfamily members. The EGFR signaling pathway is one of the most important pathways regulating cell proliferation, differentiation, survival, and growth. Overexpression and mutation in the kinase domain of EGFR have been implicated in the development and progression of a variety of cancers. A number of monoclonal antibodies and small molecule inhibitors have been developed that target EGFR, including the antibodies Cetuximab and Panitumumab, which are used in combination with other therapies for the treatment of colorectal cancer and non-small cell lung carcinoma (NSCLC). The small molecule inhibitors Gefitinib (Iressa) and Erlotinib (Tarceva), already used for NSCLC, are undergoing clinical trials for other types of cancer including gastrointestinal, breast, head and neck, and bladder. The EGFR subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
                ....*....|....*....|....*..
gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd05108 131 VHRDLAARNVLVKTPQHVKITDFGLAK 157

Catalytic domain of the Protein Tyrosine Kinase, Tropomyosin Related Kinase C; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. TrkC is a receptor PTK (RTK) containing an extracellular region with arrays of leucine-rich motifs flanked by two cysteine-rich clusters followed by two immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. Binding of TrkC to its ligand, neurotrophin 3 (NT3), results in receptor oligomerization and activation of the catalytic domain. TrkC is broadly expressed in the nervous system and in some non-neural tissues including the developing heart. NT3/TrkC signaling plays an important role in the innervation of the cardiac conducting system and the development of smooth muscle cells. Mice deficient with NT3 and TrkC have multiple heart defects. NT3/TrkC signaling is also critical for the development and maintenance of enteric neurons that are important for the control of gut peristalsis. The TrkC subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05094 142 QHFVHRDLATRNCLVGANLLVKIGDFGMSRDV 173

Catalytic domain of the Serine/Threonine Kinases, Cyclin-Dependent protein Kinase Like 2 and 3; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CDKL2, also called p56 KKIAMRE, is expressed in testis, kidney, lung, and brain. It functions mainly in mature neurons and plays an important role in learning and memory. Inactivation of CDKL3, also called NKIAMRE (NKIATRE in rat), by translocation is associated with mild mental retardation. It has been reported that CDKL3 is lost in leukemic cells having a chromosome arm 5q deletion, and may contribute to the transformed phenotype. CDKs belong to a large family of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. The CDKL2/3 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd07846 122 IHRDIKPENILVSQSGVVKLCDFGFARTL 150

Catalytic domain of the Protein Tyrosine Kinase, Fyn; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Fyn and Yrk are members of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Fyn, together with Lck, plays a critical role in T-cell signal transduction by phosphorylating ITAM (immunoreceptor tyr activation motif) sequences on T-cell receptors, ultimately leading to the proliferation and differentiation of T-cells. In addition, Fyn is involved in the myelination of neurons, and is implicated in Alzheimer's and Parkinson's diseases. Src kinases contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). The Fyn/Yrk subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05070 127 IHRDLRSANILVGNGLICKIADFGLARLI 155

Catalytic domain of the Serine/Threonine kinase, PDLIM1 interacting kinase 1 like; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PDIK1L is also called STK35 or CLIK-1. It is predominantly a nuclear protein which is capable of autophosphorylation. Through its interaction with the PDZ-LIM protein CLP-36, it is localized to actin stress fibers. The PDIK1L subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase (PI3K).

                        10        20        30
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gi 17225783  12 QCIHRDLAARNILLTHGR---ITKICDFGLAR 40
Cdd:cd13977 154 QIVHRDLKPDNILISHKRgepILKVADFGLSK 185

Catalytic domain of the Protein Tyrosine Kinase, Lyn; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Lyn is a member of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. Lyn is expressed in B lymphocytes and myeloid cells. It exhibits both positive and negative regulatory roles in B cell receptor (BCR) signaling. Lyn, as well as Fyn and Blk, promotes B cell activation by phosphorylating ITAMs (immunoreceptor tyr activation motifs) in CD19 and in Ig components of BCR. It negatively regulates signaling by its unique ability to phosphorylate ITIMs (immunoreceptor tyr inhibition motifs) in cell surface receptors like CD22 and CD5. Lyn also plays an important role in G-CSF receptor signaling by phosphorylating a variety of adaptor molecules. Src kinases contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). The Lyn subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05072 126 IHRDLRAANVLVSESLMCKIADFGLARVI 154

Catalytic domain of AGC family Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. AGC kinases regulate many cellular processes including division, growth, survival, metabolism, motility, and differentiation. Many are implicated in the development of various human diseases. Members of this family include cAMP-dependent Protein Kinase (PKA), cGMP-dependent Protein Kinase (PKG), Protein Kinase C (PKC), Protein Kinase B (PKB), G protein-coupled Receptor Kinase (GRK), Serum- and Glucocorticoid-induced Kinase (SGK), and 70 kDa ribosomal Protein S6 Kinase (p70S6K or S6K), among others. AGC kinases share an activation mechanism based on the phosphorylation of up to three sites: the activation loop (A-loop), the hydrophobic motif (HM) and the turn motif. Phosphorylation at the A-loop is required of most AGC kinases, which results in a disorder-to-order transition of the A-loop. The ordered conformation results in the access of substrates and ATP to the active site. A subset of AGC kinases with C-terminal extensions containing the HM also requires phosphorylation at this site. Phosphorylation at the HM allows the C-terminal extension to form an ordered structure that packs into the hydrophobic pocket of the catalytic domain, which then reconfigures the kinase into an active bi-lobed state. In addition, growth factor-activated AGC kinases such as PKB, p70S6K, RSK, MSK, PKC, and SGK, require phosphorylation at the turn motif (also called tail or zipper site), located N-terminal to the HM at the C-terminal extension. The AGC family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and Phosphoinositide 3-Kinase.

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gi 17225783  14 IHRDLAARNILLT-HGRItKICDFGLARDI 42
Cdd:cd05123 115 IYRDLKPENILLDsDGHI-KLTDFGLAKEL 143

Pseudokinase domain of the Protein Tyrosine Kinase, HER3; HER3 (ErbB3) is a member of the EGFR (HER, ErbB) subfamily of proteins, which are receptor PTKs (RTKs) containing an extracellular EGF-related ligand-binding region, a transmembrane helix, and a cytoplasmic region with a tyr kinase domain and a regulatory C-terminal tail. Unlike other PTKs, phosphorylation of the activation loop of EGFR proteins is not critical to their activation. Instead, they are activated by ligand-induced dimerization, leading to the phosphorylation of tyr residues in the C-terminal tail, which serve as binding sites for downstream signaling molecules. HER3 contains an impaired tyr kinase domain, which lacks crucial residues for catalytic activity against exogenous substrates but is still able to bind ATP and autophosphorylate. HER3 binds the neuregulin ligands, NRG1 and NRG2, and it relies on its heterodimerization partners for activity following ligand binding. The HER2-HER3 heterodimer constitutes a high affinity co-receptor capable of potent mitogenic signaling. HER3 participates in a signaling pathway involved in the proliferation, survival, adhesion, and motility of tumor cells. The HER3 subfamily is part of a larger superfamily that includes other pseudokinases and the the catalytic domains of active kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783   8 FLPQQC-IHRDLAARNILLTHGRITKICDFGLA 39
Cdd:cd05111 124 YLEEHRmVHRNLAARNVLLKSPSQVQVADFGVA 156

The catalytic domain of CAMK family Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CaMKs are multifunctional calcium and calmodulin (CaM) stimulated STKs involved in cell cycle regulation. There are several types of CaMKs including CaMKI, CaMKII, and CaMKIV. CaMKI proteins are monomeric and they play pivotal roles in the nervous system, including long-term potentiation, dendritic arborization, neurite outgrowth, and the formation of spines, synapses, and axons. CaMKII is a signaling molecule that translates upstream calcium and reactive oxygen species (ROS) signals into downstream responses that play important roles in synaptic function and cardiovascular physiology. CAMKIV is implicated in regulating several transcription factors like CREB, MEF2, and retinoid orphan receptors, as well as in T-cell development and signaling. The CAMK family also consists of other related kinases including the Phosphorylase kinase Gamma subunit (PhKG), the C-terminal kinase domains of Ribosomal S6 kinase (RSK) and Mitogen and stress-activated kinase (MSK), Doublecortin-like kinase (DCKL), and the MAPK-activated protein kinases MK2, MK3, and MK5, among others. The CAMK family is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRIT---KICDFGLARDIR 43
Cdd:cd05117 121 VHRDLKPENILLASKDPDspiKIIDFGLAKIFE 153

Catalytic domain of the Serine/Threonine kinase, Liver Kinase B1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. LKB1, also called STK11, was first identified as a tumor suppressor responsible for Peutz-Jeghers syndrome, a disorder that leads to an increased risk of spontaneous epithelial cancer. It serves as a master upstream kinase that activates AMP-activated protein kinase (AMPK) and most AMPK-like kinases. LKB1 and AMPK are part of an energy-sensing pathway that links cell energy to metabolism and cell growth. They play critical roles in the establishment and maintenance of cell polarity, cell proliferation, cytoskeletal organization, as well as T-cell metabolism, including T-cell development, homeostasis, and effector function. To be activated, LKB1 requires the adaptor proteins STe20-Related ADaptor (STRAD) and mouse protein 25 (MO25). The LKB1 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd14119 116 QGIIHKDIKPGNLLLTTDGTLKISDFGVAEAL 147

Catalytic domain of the Serine/Threonine Kinases, Mitogen-Activated Protein Kinase Kinase Kinases 12 and 13; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MAP3K12 is also called MAPK upstream kinase (MUK), dual leucine zipper-bearing kinase (DLK) or leucine-zipper protein kinase (ZPK). It is involved in the c-Jun N-terminal kinase (JNK) pathway that directly regulates axonal regulation through the phosphorylation of microtubule-associated protein 1B (MAP1B). It also regulates the differentiation of many cell types including adipocytes and may play a role in adipogenesis. MAP3K13, also called leucine zipper-bearing kinase (LZK), directly phosphorylates and activates MKK7, which in turn activates the JNK pathway. It also activates NF-kB through IKK activation and this activity is enhanced by antioxidant protein-1 (AOP-1). MAP3Ks (MKKKs or MAPKKKs) phosphorylate and activate MAP2Ks (MAPKKs or MKKs), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. The MAP3K12/13 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDIR 43
Cdd:cd14059 103 IHRDLKSPNVLVTYNDVLKISDFGTSKELS 132

Catalytic domain of the Protein Tyrosine Kinase, Tropomyosin Related Kinase B; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. TrkB is a receptor PTK (RTK) containing an extracellular region with arrays of leucine-rich motifs flanked by two cysteine-rich clusters followed by two immunoglobulin-like domains, a transmembrane segment, and an intracellular catalytic domain. Binding of TrkB to its ligands, brain-derived neurotrophic factor (BDNF) or neurotrophin 4 (NT4), results in receptor oligomerization and activation of the catalytic domain. TrkB is broadly expressed in the nervous system and in some non-neural tissues. It plays important roles in cell proliferation, differentiation, and survival. BDNF/Trk signaling plays a key role in regulating activity-dependent synaptic plasticity. TrkB also contributes to protection against gp120-induced neuronal cell death. TrkB overexpression is associated with poor prognosis in neuroblastoma (NB) and other human cancers. It acts as a suppressor of anoikis (detachment-induced apoptosis) and contributes to tumor metastasis. The TrkB subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20        30
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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05093 139 QHFVHRDLATRNCLVGENLLVKIGDFGMSRDV 170

Catalytic domain of the Serine/Threonine Kinases, Plant TEY Mitogen-Activated Protein Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Plant MAPKs are typed based on the conserved phosphorylation motif present in the activation loop, TEY and TDY. This subfamily represents the TEY subtype of plant MAPKs and is further subdivided into three groups (A, B, and C). Group A is represented by AtMPK3, AtMPK6, Nicotiana tabacum BTF4 (NtNTF4), among others. They are mostly involved in environmental and hormonal responses. AtMPK3 and AtMPK6 are also key regulators for stomatal development and patterning. Group B is represented by AtMPK4, AtMPK13, and NtNTF6, among others. They may be involved in both cell division and environmental stress response. AtMPK4 also participates in regulating innate immunity. Group C is represented by AtMPK1, AtMPK2, NtNTF3, Oryza sativa MAPK4 (OsMAPK4), among others. They may also be involved in stress responses. AtMPK1 and AtMPK2 are activated following mechanical injury and in the presence of stress chemicals such as jasmonic acid, hydrogen peroxide and abscisic acid. OsMAPK4 is also called OsMSRMK3 for Multiple Stress-Responsive MAPK3. In plants, MAPKs are associated with physiological, developmental, hormonal, and stress responses. Some plants show numerous gene duplications of MAPKs; Arabidopsis thaliana harbors at least 20 MAPKs, named AtMPK1-20. The TEY MAPK subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                        10        20
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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd07858 130 LHRDLKPSNLLLNANCDLKICDFGLAR 156

Catalytic domain of the Protein Serine/Threonine Kinase, Never In Mitosis gene A (NIMA)-related kinase 1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Nek1 is associated with centrosomes throughout the cell cycle. It is involved in the formation of primary cilium and in the maintenance of centrosomes. It cycles through the nucleus and may be capable of relaying signals between the cilium and the nucleus. Nek1 is implicated in the development of polycystic kidney disease, which is characterized by benign polycystic tumors formed by abnormal overgrowth of renal epithelial cells. It appears also to be involved in DNA damage response, and may be important for both correct DNA damage checkpoint activation and DNA repair. Nek1 is one in a family of 11 different Neks (Nek1-11) that are involved in cell cycle control. The Nek family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  11 QQCIHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd08218 120 RKILHRDIKSQNIFLTKDGIIKLGDFGIAR 149

Catalytic domain of cyclin G-Associated Kinase-like proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily includes cyclin G-Associated Kinase (GAK), Drosophila melanogaster Numb-Associated Kinase (NAK)-like proteins, and similar protein kinases. GAK plays regulatory roles in clathrin-mediated membrane trafficking, the maintenance of centrosome integrity and chromosome congression, neural patterning, survival of neurons, and immune responses. NAK plays a role in asymmetric cell division through its association with Numb. It also regulates the localization of Dlg, a protein essential for septate junction formation. The GAK-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLA 39
Cdd:cd13985 127 IHRDIKIENILFSNTGRFKLCDFGSA 152

Catalytic domain of the Protein Tyrosine Kinase, Insulin-like Growth Factor-1 Receptor; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. IGF-1R is a receptor PTK (RTK) that is composed of two alphabeta heterodimers. Binding of the ligand (IGF-1 or IGF-2) to the extracellular alpha subunit activates the intracellular tyr kinase domain of the transmembrane beta subunit. Receptor activation leads to autophosphorylation, which stimulates downstream kinase activities and biological function. IGF-1R signaling is important in the differentiation, growth, and survival of normal cells. In cancer cells, where it is frequently overexpressed, IGF-1R is implicated in proliferation, the suppression of apoptosis, invasion, and metastasis. IGF-1R is being developed as a therapeutic target in cancer treatment. The IGF-1R subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05062 141 VHRDLAARNCMVAEDFTVKIGDFGMTRDI 169

cyclin-dependent protein kinase; Provisional

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gi 17225783   14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:PTZ00024 141 MHRDLSPANIFINSKGICKIADFGLAR 167

Catalytic domain of the Protein Tyrosine Kinase, Yes; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Yes (or c-Yes) is a member of the Src subfamily of proteins, which are cytoplasmic (or non-receptor) PTKs. c-Yes kinase is the cellular homolog of the oncogenic protein (v-Yes) encoded by the Yamaguchi 73 and Esh sarcoma viruses. It displays functional overlap with other Src subfamily members, particularly Src. It also shows some unique functions such as binding to occludins, transmembrane proteins that regulate extracellular interactions in tight junctions. Yes also associates with a number of proteins in different cell types that Src does not interact with, like JAK2 and gp130 in pre-adipocytes, and Pyk2 in treated pulmonary vein endothelial cells. Although the biological function of Yes remains unclear, it appears to have a role in regulating cell-cell interactions and vesicle trafficking in polarized cells. Src kinases contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). The Yes subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase (PI3K).

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05069 130 IHRDLRAANILVGDNLVCKIADFGLARLI 158

Catalytic domain of the Serine/Threonine kinase, eukaryotic translation Initiation Factor 2-Alpha Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. EIF2AKs phosphorylate the alpha subunit of eIF-2, resulting in the downregulation of protein synthesis. eIF-2 phosphorylation is induced in response to cellular stresses including virus infection, heat shock, nutrient deficiency, and the accummulation of unfolded proteins, among others. There are four distinct kinases that phosphorylate eIF-2 and control protein synthesis under different stress conditions: General Control Non-derepressible-2 (GCN2) which is activated during amino acid or serum starvation; protein kinase regulated by RNA (PKR) which is activated by double stranded RNA; heme-regulated inhibitor kinase (HRI) which is activated under heme-deficient conditions; and PKR-like endoplasmic reticulum kinase (PERK) which is activated when misfolded proteins accumulate in the ER. The EIF2AK subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHG-RITKICDFGLARDI 42
Cdd:cd13996 129 VHRDLKPSNIFLDNDdLQVKIGDFGLATSI 158

Catalytic domain of the Serine/Threonine Kinase, Cell Cycle-Related Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CCRK was previously called p42. It is a Cyclin-Dependent Kinase (CDK)-Activating Kinase (CAK) which is essential for the activation of CDK2. It is indispensable for cell growth and has been implicated in the progression of glioblastoma multiforme. In the heart, a splice variant of CCRK with a different C-terminal half is expressed; this variant promotes cardiac cell growth and survival and is significantly down-regulated during the development of heart failure. The CCRK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLAR 40
Cdd:cd07832 122 MHRDLKPANLLISSTGVLKIADFGLAR 148

Catalytic Domain of TAM (Tyro3, Axl, Mer) Protein Tyrosine Kinases; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. The TAM subfamily consists of Tyro3 (or Sky), Axl, Mer (or Mertk), and similar proteins. TAM subfamily members are receptor tyr kinases (RTKs) containing an extracellular ligand-binding region with two immunoglobulin-like domains followed by two fibronectin type III repeats, a transmembrane segment, and an intracellular catalytic domain. Binding to their ligands, Gas6 and protein S, leads to receptor dimerization, autophosphorylation, activation, and intracellular signaling. TAM proteins are implicated in a variety of cellular effects including survival, proliferation, migration, and phagocytosis. They are also associated with several types of cancer as well as inflammatory, autoimmune, vascular, and kidney diseases. The TAM subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05035 135 IHRDLAARNCMLDENMTVCVADFGLSRKI 163

Catalytic domain of the Protein Tyrosine Kinase, Tyro3; PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Tyro3 (or Sky) is predominantly expressed in the central nervous system and the brain, and functions as a neurotrophic factor. It is also expressed in osteoclasts and has a role in bone resorption. Tyro3 is a member of the TAM subfamily, composed of receptor PTKs (RTKs) containing an extracellular ligand-binding region with two immunoglobulin-like domains followed by two fibronectin type III repeats, a transmembrane segment, and an intracellular catalytic domain. Binding to their ligands, Gas6 and protein S, leads to receptor dimerization, autophosphorylation, activation, and intracellular signaling. The Tyro3 subfamily is part of a larger superfamily that includes the catalytic domains of other kinases such as serine/threonine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 17225783  14 IHRDLAARNILLTHGRITKICDFGLARDI 42
Cdd:cd05074 145 IHRDLAARNCMLNENMTVCVADFGLSKKI 173