ubiquitin-like (Ubl) domain found in ubiquitin-like protein FUBI and similar proteins; FUBI is a pro-apoptotic regulatory gene FAU encoding ubiquitin-like protein with ribosomal protein S30 as a C-terminal extension. FUBI functions as a tumor suppressor protein that may be involved in the ATP-dependent proteolytic activity of ubiquitin. The N-terminal ubiquitin-like (Ubl) domain of FUBI has the beta-grasp Ubl fold, and it may act as a substitute or an inhibitor of ubiquitin or one of ubiquitin's close relatives UCRP, FAT10, and Nedd8.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 298919223   1 MQLFVRAQELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGRMLGG 74
Cdd:cd01793    1 MQLFVRAQSLHTLEVSGNETVADIKAHIAALEGIAVEDQVLLYAGAPLEDDVVLGQCGIPDLATLEVAVRLLGG 74

ubiquitin-like (Ubl) domain found in ubiquitin-like protein FUBI and similar proteins; FUBI is a pro-apoptotic regulatory gene FAU encoding ubiquitin-like protein with ribosomal protein S30 as a C-terminal extension. FUBI functions as a tumor suppressor protein that may be involved in the ATP-dependent proteolytic activity of ubiquitin. The N-terminal ubiquitin-like (Ubl) domain of FUBI has the beta-grasp Ubl fold, and it may act as a substitute or an inhibitor of ubiquitin or one of ubiquitin's close relatives UCRP, FAT10, and Nedd8.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 298919223   1 MQLFVRAQELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGRMLGG 74
Cdd:cd01793    1 MQLFVRAQSLHTLEVSGNETVADIKAHIAALEGIAVEDQVLLYAGAPLEDDVVLGQCGIPDLATLEVAVRLLGG 74

Ubiquitin homologues; Ubiquitin-mediated proteolysis is involved in the regulated turnover of proteins required for controlling cell cycle progression

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 298919223     1 MQLFVRAQ--ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGR 70
Cdd:smart00213   1 IELTVKTLdgKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

Ubiquitin [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 298919223   1 MQLFVRAQ--ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGRMLG 73
Cdd:COG5272    1 MQIFVKTLtgKTITLEVEPNDTIEAVKAKIQDKEGIPPDQQRLIFAGKQLEDDRTLADYNIQKESTLHLVTRTLG 75

Ribosomal protein S30 [Translation, ribosomal structure and biogenesis]; Ribosomal protein S30 is part of the Pathway/BioSystem: Archaeal ribosomal proteins

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 298919223  77 HGSLARAGKVRGQTPkVAKQEKKKKKTGRAKRRMQYNRRFV 117
Cdd:COG4919    4 HGSLTKAGKVRSQTP-KIPAKPRKNPPPRVRNRREYRKRFV 43

ubiquitin-like (Ubl) domain found in ubiquitin-like protein FUBI and similar proteins; FUBI is a pro-apoptotic regulatory gene FAU encoding ubiquitin-like protein with ribosomal protein S30 as a C-terminal extension. FUBI functions as a tumor suppressor protein that may be involved in the ATP-dependent proteolytic activity of ubiquitin. The N-terminal ubiquitin-like (Ubl) domain of FUBI has the beta-grasp Ubl fold, and it may act as a substitute or an inhibitor of ubiquitin or one of ubiquitin's close relatives UCRP, FAT10, and Nedd8.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 298919223   1 MQLFVRAQELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGRMLGG 74
Cdd:cd01793    1 MQLFVRAQSLHTLEVSGNETVADIKAHIAALEGIAVEDQVLLYAGAPLEDDVVLGQCGIPDLATLEVAVRLLGG 74

Ubiquitin homologues; Ubiquitin-mediated proteolysis is involved in the regulated turnover of proteins required for controlling cell cycle progression

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 298919223     1 MQLFVRAQ--ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGR 70
Cdd:smart00213   1 IELTVKTLdgKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

ubiquitin-like (Ubl) domain found in ubiquitin and ubiquitin-like Ubl proteins; Ubiquitin-like (Ubl) proteins have a similar ubiquitin (Ub) beta-grasp fold and attach to other proteins in a Ubl manner but with biochemically distinct roles. Ub and Ubl proteins conjugate and deconjugate via ligases and peptidases to covalently modify target polypeptides. Some Ubl domains have adaptor roles in Ub-signaling by mediating protein-protein interaction. Prokaryotic sulfur carrier proteins are Ub-related proteins that can be activated in an ATP-dependent manner. Polyubiquitination signals for a diverse set of cellular events via different isopeptide linkages formed between the C terminus of one ubiquitin (Ub) and the epsilon-amine of K6, K11, K27, K29, K33, K48, or K63 of a second Ub. One of these seven lysine residues (K27, Ub numbering) is conserved in this Ubl_ubiquitin_like family. K27-linked Ub chains are versatile and can be recognized by several downstream receptor proteins. K27 has roles beyond chain linkage, such as in Ubl NEDD8 (which contains many of the same lysines (K6, K11, K27, K33, K48) as Ub) where K27 has a role (other than conjugation) in the mechanism of protein neddylation.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 298919223   3 LFVR--AQELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEV 67
Cdd:cd17039    1 ITVKtlDGKTYTVEVDPDDTVADLKEKIEEKTGIPVEQQRLIYNGKELKDDKTLSDYGIKDGSTIHL 67

ubiquitin-like (Ubl) domain 2 found in interferon-stimulated gene 15 (ISG15) and similar proteins; ISG15, also termed interferon-induced 15 kDa protein, or interferon-induced 17 kDa protein (IP17), or ubiquitin cross-reactive protein (UCRP), is an antiviral interferon-induced ubiquitin-like protein that upon viral infection it modifies cellular and viral proteins by mechanisms similar to ubiquitination. Although ISG15 has properties similar to those of other ubiquitin-like (Ubl) molecules, it is a unique member of the Ubl superfamily, whose expression and conjugation to target proteins are tightly regulated by specific signaling pathways, indicating it may have specialized functions in the immune system. ISG15 contains two tandem Ubl domains with a beta-grasp Ubl fold. This family corresponds to the second Ubl domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 298919223   1 MQLFVRAQ--ELHTLEVTGQETVAQIKDHVASLEGIaPEDQVVLL-AGSPLEDEATLGQCGVEALTTLEVAGRM 71
Cdd:cd01810    1 LSIFVRNEkgQSHTYEVRLTQTVDQLKQKVSGREGV-HDDQFWLTfEGRPLEDQLPLGEYGLKPQSTIHMNLRL 73

ubiquitin-like (Ubl) domain found in ubiquitin; Ubiquitin is a protein modifier in eukaryotes that is involved in various cellular processes, including transcriptional regulation, cell cycle control, and DNA repair. Ubiquitination is comprised of a cascade of E1, E2 and E3 enzymes that results in a covalent bond between the C-terminus of ubiquitin and the epsilon-amino group of a substrate lysine. Ubiquitin-like (Ubl) proteins have similar ubiquitin beta-grasp fold and attach to other proteins in a Ubl manner but with biochemically distinct roles. Ubiquitin (Ub)and Ubl proteins conjugate and deconjugate via ligases and peptidases to covalently modify target polypeptides. Ub includes Ubq/RPL40e and Ubq/RPS27a fusions as well as homopolymeric multiubiquitin protein chains.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 298919223   1 MQLFVRA--QELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGRMLGG 74
Cdd:cd01803    1 MQIFVKTltGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 76

ubiquitin-like (Ubl) domain found in the Rad23 protein family; The Rad23 family includes the yeast nucleotide excision repair (NER) proteins, Rad23p (in Saccharomyces cerevisiae) and Rhp23p (in Schizosaccharomyces pombe), their mammalian orthologs HR23A and HR23B, and putative DNA repair proteins from plants. Rad23 proteins play dual roles in DNA repair as well as in proteosomal degradation. They have affinity for both the proteasome and ubiquitinylated proteins and participate in translocating polyubiquitinated proteins to the proteasome. Rad23 proteins carry an ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, and two ubiquitin-associated (UBA) domains, as well as a xeroderma pigmentosum group C (XPC) protein-binding domain. The Ubl domain is responsible for the binding to proteasome. The UBA domains are important for binding of ubiquitin (Ub) or multi-ubiquitinated substrates, which suggests Rad23 proteins might be involved in certain pathways of Ub metabolism. Both the Ubl domain and the XPC-binding domain are necessary for efficient NER function of Rad23 proteins.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 298919223   1 MQLFVR--AQELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLL-AGSPLEDEATLGQCGVE 60
Cdd:cd01805    1 MKITFKtlQQQTFEIEVEPSDTVLELKEKIEQEQGDFPASGQKLIySGKVLKDDKTLSEYNIK 63

ubiquitin-like (Ubl) domain found in ubiquitin-specific-processing protease 48 (USP48) and similar proteins; USP48, also termed USP31, or deubiquitinating enzyme 48, or ubiquitin thioesterase 48, or ubiquitin carboxyl-terminal hydrolase 48, belongs to the ubiquitin specific protease (USP) family that is one of at least seven deubiquitylating enzyme (DUB) families capable of deconjugating ubiquitin (Ub)and ubiquitin-like (Ubl) adducts. While the USP proteins have a conserved catalytic core domain, USP48 differs in its domain architecture. It contains an N-terminal USP domain, three DUSP (domain present in ubiquitin-specific protease) domains, and a C-terminal Ubl domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions. USP48 is a deubiquitinating enzyme that interacts with TNF receptor-associated factor 2 (TRAF2) and has been implicated in activation of nuclear factor-kappaB (NF-kappaB). Moreover, as a nuclear deubiquitinase regulated by casein kinase 2 (CK2), USP48 controls the ubiquitin/proteasome-system (UPS)-dependent turnover of activated NF-kappaB/RelA in the nucleus together with the COP9 signalosome, suggesting a role of USP48 in a timely control of immune responses.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 298919223   9 ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDE-ATLGQCGVEALTTLEV 67
Cdd:cd01795    6 ERKSLTVSSTTTLKELKLQIMEKFSVAPFDQHLYFNGRELTDDsATLADLGILPGDVLYL 65

ubiquitin-like (Ubl) domain 1 found in leukocyte antigen F (HLA-F) adjacent transcript 10 (FAT10) and similar proteins; FAT10, also termed ubiquitin D (UBD), or diubiquitin, is a cytokine-inducible ubiquitin-like (Ubl) modifer that is highly expressed in the thymus, and targets substrates covalently for 26S proteasomal degradation. It is also associated with cancer development, antigen processing and antimicrobial defense, chromosomal stability and cell cycle regulation. FAT10 is presented on immune cells and under the inflammatory conditions, is synergistically induced by interferon gamma (IFNgamma) and tumor necrosis factor (TNFalpha) in the non-immune (liver parenchymal) cells. FAT10 contains two Ubl domains. The family corresponds to the first Ubl domain of FAT10. Some family members contain only one Ubl domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 298919223   9 ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEV 67
Cdd:cd17052   10 DLMTFDANPQDSVKKINEHVRSKTKVPVQDQVLLLGSKILKPRRRLSSYGIDKEKTIHL 68

ubiquitin-like (Ubl) domain found in AN1-type zinc finger protein 4 (ZFAND4) and similar proteins; ZFAND4, also termed AN1-type zinc finger and ubiquitin domain-containing protein-like 1 (ANUBL1), may function as an oncogene that promotes proliferation and regulates relevant tumor suppressor genes in gastric cancer, suggesting a role in gastric cancer initiation and progression. ZFAND4contains an N-terminal ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions, as well as a C-terminal AN1-type zinc finger. Unlike ubiquitin polyproteins and most ubiquitin fusion proteins, the N-terminal Ubl domain of ZFAND4 does not undergo proteolytic processing.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 298919223   1 MQLFVRA--QELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTL 65
Cdd:cd01802    1 MELFIETltGTAFELRVSPFETVASVKAKIQRLEGIPVSQQHLIWSGRELEDDYCLHDYNITDGSTL 67

ubiquitin-like (Ubl) domain found in eukaryotic protein linking integrin-associated protein (IAP, also known as CD47) with cytoskeleton (PLIC) proteins; The PLIC proteins (or ubiquilins) family contains human homologs of the yeast ubiquitin-like (Ubl) Dsk2 protein, PLIC-1 (also termed ubiquilin-1), PLIC-2 (also termed ubiquilin-2, or Chap1), PLIC-3 (also termed ubiquilin-3) and PLIC-4 (also termed ubiquilin-4, ataxin-1 interacting ubiquitin-like protein, A1Up, connexin43-interacting protein of 75 kDa, or CIP75), and mouse PLIC proteins. They are ubiquitin (Ub)-binding adaptor proteins involved in all protein degradation pathways through delivering ubiquitinated substrates to proteasomes. They also promote autophagy-dependent cell survival during nutrient starvation. PLIC-1 regulates the function of the thrombospondin receptor CD47 and G protein signaling. It plays a role in TLR4-mediated signaling through interacting with the Toll/interleukin-1 receptor (TIR) domain of TLR4. It also inhibits the TLR3-Trif antiviral pathway by reducing the abundance of Trif. Moreover, PLIC-1 binds to gamma-aminobutyric acid receptors (GABAARs) and modulates the Ub-dependent, proteasomal degradation of GABAARs. Furthermore, PLIC-1 acts as a molecular chaperone regulating amyloid precursor protein (APP) biosynthesis, trafficking, and degradation by stimulating K63-linked polyubiquitination of lysine 688 in the APP intracellular domain. In addition, PLIC-1 is involved in the protein aggregation-stress pathway via associating with the Ub-interacting motif (UIM) proteins ataxin 3, HSJ1a, and epidermal growth factor substrate 15 (EPS15). PLIC-2 is a protein that binds the ATPase domain of the HSP70-like Stch protein. It functions as a negative regulator of G protein-coupled receptor (GPCR) endocytosis. It also involved in amyotrophic lateral sclerosis (ALS)-related dementia. PLIC-3 is encoded by UbiquilinN3, a testis-specific gene. It shows high sequence similarity with the Xenopus protein XDRP1, a nuclear phosphoprotein that binds to the N-terminus of cyclin A and inhibits Ca2+-induced degradation of cyclin A, but not cyclin B. PLIC-4 is an ubiquitin-like (Ubl) nuclear protein that interacts with ataxin-1 and further links ataxin-1 with the chaperone and Ub-proteasome pathways. It also binds to the non-ubiquitinated gap junction protein connexin43 (Cx43) and regulates the turnover of Cx43 through the proteasomal pathway. PLIC proteins contain an N-terminal Ubl domain that is responsible for the binding of Ub-interacting motifs (UIMs) expressed by proteasomes and endocytic adaptors, and C-terminal Ub-associated (UBA) domain that interacts with Ub chains present on proteins destined for proteasomal degradation. In addition, mammalian PLIC2 proteins have an extra collagen-like motif region, which is absent in other PLIC proteins and the yeast Dsk2 protein.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 298919223   7 AQELHTLEVTGQETVAQIKDHVASLEGiAPEDQVVLL-AGSPLEDEATLGQCGV 59
Cdd:cd01808   10 PKEKEDFEVPEDSSVKEFKEEISKKFK-APVEQLVLIfAGKILKDQDTLSQHGI 62

ubiquitin-like (Ubl) domain found in neural precursor cell expressed developmentally down-regulated protein 8 (NEDD8) and similar proteins; NEDD8, also termed Neddylin, or RELATED TO UBIQUITIN (RUB/Rub1p) in plant and yeast, is a ubiquitin-like protein that conjugates to nuclear proteins in a manner analogous to ubiquitination and sentrinization. It modifies a family of molecular scaffold proteins called cullins that are responsible for assembling the ROC1/Rbx1 RING-based E3 ubiquitin ligases, of which several play a direct role in tumorigenesis. NEDD8 deamidation and its inhibition of Cullin-RING ubiquitin ligases (CRLs) activity are responsible for Cycle-inhibiting factor (Cif)/Cif homolog in Burkholderia pseudomallei (CHBP)-induced cytopathic effect. NEDD8 contains a single conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions. Polyubiquitination, signals for a diverse set of cellular events via different isopeptide linkages formed between the C terminus of one ubiquitin (Ub) and the epsilon-amine of K6, K11, K27, K29, K33, K48, or K63 of a second Ub. Ubl NEDD8, contains many of the same lysines (K6, K11, K27, K33, K48) as Ub, where K27 has an role (other than conjugation) in the mechanism of protein neddylation.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 298919223  13 LEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTTLEVAGRMLGG 74
Cdd:cd01806   13 IDIEPTDKVERIKERVEEKEGIPPQQQRLIFSGKQMNDEKTAADYKIEGGSVLHLVLALRGG 74

ubiquitin-like (Ubl) domain found in transcription elongation factor B (Elongin B) and similar proteins; Elongin B, also termed Elongin 18 kDa subunit, or EloB, or RNA polymerase II transcription factor SIII subunit B (SIII p18), is part of an E3 ubiquitin ligase complex called VEC that activates ubiquitination by the E2 ubiquitin-conjugating enzyme Ubc5. VEC is composed of von Hippel-Lindau tumor suppressor protein (pVHL), elongin C, cullin 2, NEDD8, and Rbx1. ElonginB binds elonginC to form the elonginBC complex which is a positive regulator of RNA polymerase II elongation factor Elongin A. The BC complex then binds VHL (von Hippel-Lindau) tumor suppressor protein to form a VCB ternary complex. Elongin B has a ubiquitin-like (Ubl) domain. Ub has a beta-grasp Ubl fold, a common structure involved in protein-protein interactions. Ub is a protein modifier in eukaryotes that is involved in various cellular processes, including transcriptional regulation, cell cycle control, and DNA repair.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 298919223   3 LFVRAQELHT-LEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLGQCGVEALTT 64
Cdd:cd01788    4 LMIRRKKTTIfTDAKESTTVFELKKIIEGILKRPPEDQRLYKDDQLLDDTKTLGDCGFTSQTA 66

ubiquitin-like (Ubl) domain found in non-canonical Inhibitor of kappa B kinases IKKepsilon and TBK1, and similar proteins; IKKepsilon and TBK1 (TRAF family member-associated NF-kappaB activator-binding kinase 1) are non-canonical members of IKK family. They have been characterized as activators of nuclear factor-kappaB (NF-kappaB), but they are not essential for NF-kappaB activation. They play critical roles in antiviral response via phosphorylation and activation of transcription factors IRF3, IRF7, STAT1 and STAT3. They are also involved in the survival, tumorigenesis and development of various cancers. Both IKKepsilon and TBK1 contain an N-terminal protein kinase domain followed a ubiquitin-like (Ubl) domain. The Ubl domain acts as a protein-protein interaction domain, and has been implicated in regulating kinase activity, which modulates interactions in the interferon pathway.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 298919223   9 ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLAGSPLEDEATLgQCGVEALTTLE 66
Cdd:cd12219   13 ELLKIYLDPTETLAEFQELIAEQTEIPAKNQLLLFEGQLLEEEVTL-PVSDYPKTTEE 69

ubiquitin-like (Ubl) domain found in inhibitor of nuclear factor kappa-B kinases, IKK-alpha and IKK-beta, and similar proteins; IKK, also termed IkappaB kinase, is an enzyme complex involved in propagating the cellular response to inflammation. It is part of the upstream nuclear factor kappa-B kinase (NF-kappaB) signal transduction cascade, and plays an important role in regulating the NF-kappaB transcription factor. IKK is composed of three subunits, IKK-alpha/CHUK, IKK-beta/IKBKB, and IKK-gamma/NEMO. The IKK-alpha and IKK-beta subunits together are catalytically active whereas the IKK-gamma subunit serves a regulatory function. IKK-alpha and IKK-beta phosphorylate the IkappaB proteins, marking them for degradation via ubiquitination and allowing NF-kappaB transcription factors to go into the nucleus. IKK-alpha, also known as IKK-A, or IkappaB kinase A (IkBKA), or conserved helix-loop-helix ubiquitous kinase (CHUK), or I-kappa-B kinase 1 (IKK1), or nuclear factor NF-kappa-B inhibitor kinase alpha (NFKBIKA), or transcription factor 16 (TCF-16), belongs to the serine/threonine protein kinase family. In addition to NF-kappaB response, it has many additional cellular targets in an NF-kappaB-independent manner. For instance, it plays a role in epidermal differentiation, as well as in the regulation of the cell cycle protein cyclin D1. IKK-beta, also known as IKK-B, or IkappaB kinase B (IkBKB), or I-kappa-B kinase 2 (IKK2), or nuclear factor NF-kappa-B inhibitor kinase beta (NFKBIKB), belongs to the serine/threonine protein kinase family as well. It interacts with many different protein partners and has been implicated in the treatment of many inflammatory diseases and cancers. Both IKK-alpha and IKK-beta contain an N-terminal catalytic domain followed by a conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 298919223   9 ELHTLEVTGQETVAQIKDHVASLEGIAPEDQVVLLA-GSPLEDEATLGQC 57
Cdd:cd17046   12 RILSYEVTEDTSLSTLQSWIERDTGIPVEDQELLLPtGVSLDPEKPASQC 61