ubiquitin-like (Ubl) domain found in ubiquitin-like proteins UBL4A and similar proteins; UBL4A, also termed GdX, is a ubiquitously expressed ubiquitin-like (Ubl) protein that forms a complex with partner proteins and participates in the protein processing through endoplasmic reticulum (ER), acting as a chaperone. As a key component of the BCL2-associated athanogene 6 (BAG6) chaperone complex, UBL4A plays a role in mediating DNA damage signaling and cell death. UBL4A also regulates insulin-induced Akt plasma membrane translocation through promotion of Arp2/3-dependent actin branching. Moreover, UBL4A specifically stabilizes the TC45/STAT3 association and promotes dephosphorylation of STAT3 to repress tumorigenesis. UBL4B is testis-specific, and encoded by an X-derived retrogene Ubl4b, which is specifically expressed in post-meiotic germ cells in mammals. As a germ cell-specific cytoplasmic protein, UBL4B is not present in somatic cells. Moreover, UBL4B is present in elongated spermatids, but not in spermatocytes and round spermatids, suggesting its function is restricted to late spermiogenesis. The function of UBL4A may be compensated by either UBL4B or other Ubl proteins in normal conditions. Both UBL4A and UBL4B contain a conserved Ubl domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01807   1 MLITVKILQGKECTIEVSPTESVLTVKQLVAEQLNVPVSQQRLVFKGKTLADEHSLSDYSIGPGSKIHLVVK 72

ubiquitin-like (Ubl) domain found in ubiquitin-like proteins UBL4A and similar proteins; UBL4A, also termed GdX, is a ubiquitously expressed ubiquitin-like (Ubl) protein that forms a complex with partner proteins and participates in the protein processing through endoplasmic reticulum (ER), acting as a chaperone. As a key component of the BCL2-associated athanogene 6 (BAG6) chaperone complex, UBL4A plays a role in mediating DNA damage signaling and cell death. UBL4A also regulates insulin-induced Akt plasma membrane translocation through promotion of Arp2/3-dependent actin branching. Moreover, UBL4A specifically stabilizes the TC45/STAT3 association and promotes dephosphorylation of STAT3 to repress tumorigenesis. UBL4B is testis-specific, and encoded by an X-derived retrogene Ubl4b, which is specifically expressed in post-meiotic germ cells in mammals. As a germ cell-specific cytoplasmic protein, UBL4B is not present in somatic cells. Moreover, UBL4B is present in elongated spermatids, but not in spermatocytes and round spermatids, suggesting its function is restricted to late spermiogenesis. The function of UBL4A may be compensated by either UBL4B or other Ubl proteins in normal conditions. Both UBL4A and UBL4B contain a conserved Ubl domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01807   1 MLITVKILQGKECTIEVSPTESVLTVKQLVAEQLNVPVSQQRLVFKGKTLADEHSLSDYSIGPGSKIHLVVK 72

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 7657667       1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:smart00213   1 IELTVKTLDGKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

ubiquitin; Provisional

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657667     1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:PTZ00044   1 MQILIKTLTGKKQSFNFEPDNTVQQVKMALQEKEGIDVKQIRLIYSGKQMSDDLKLSDYKVVPGSTIHMVLQ 72

ubiquitin-like (Ubl) domain found in ubiquitin-like proteins UBL4A and similar proteins; UBL4A, also termed GdX, is a ubiquitously expressed ubiquitin-like (Ubl) protein that forms a complex with partner proteins and participates in the protein processing through endoplasmic reticulum (ER), acting as a chaperone. As a key component of the BCL2-associated athanogene 6 (BAG6) chaperone complex, UBL4A plays a role in mediating DNA damage signaling and cell death. UBL4A also regulates insulin-induced Akt plasma membrane translocation through promotion of Arp2/3-dependent actin branching. Moreover, UBL4A specifically stabilizes the TC45/STAT3 association and promotes dephosphorylation of STAT3 to repress tumorigenesis. UBL4B is testis-specific, and encoded by an X-derived retrogene Ubl4b, which is specifically expressed in post-meiotic germ cells in mammals. As a germ cell-specific cytoplasmic protein, UBL4B is not present in somatic cells. Moreover, UBL4B is present in elongated spermatids, but not in spermatocytes and round spermatids, suggesting its function is restricted to late spermiogenesis. The function of UBL4A may be compensated by either UBL4B or other Ubl proteins in normal conditions. Both UBL4A and UBL4B contain a conserved Ubl domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01807   1 MLITVKILQGKECTIEVSPTESVLTVKQLVAEQLNVPVSQQRLVFKGKTLADEHSLSDYSIGPGSKIHLVVK 72

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 7657667       1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
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 7657667    3 LTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLV 70
Cdd:cd17039   1 ITVKTLDGKTYTVEVDPDDTVADLKEKIEEKTGIPVEQQRLIYNGKELKDDKTLSDYGIKDGSTIHLV 68

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 7657667    5 VKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLV 70
Cdd:cd01806   3 VKTLTGKEIEIDIEPTDKVERIKERVEEKEGIPPQQQRLIFSGKQMNDEKTAADYKIEGGSVLHLV 68

ubiquitin-like (Ubl) domain found in BCL2-associated athanogene 6 (BAG6) and similar proteins; BAG6, also termed large proline-rich protein BAG6, or BAG family molecular chaperone regulator 6, or HLA-B-associated transcript 3 (Bat3), or protein Scythe, or protein G3, is a nucleo-cytoplasmic shuttling chaperone protein that is highly conserved in eukaryotes. It functions in two distinct biological pathways, ubiquitin-mediated protein degradation of defective polypeptides and tail-anchored transmembrane protein biogenesis in mammals. BAG6 is a component of the heterotrimeric BAG6 sortase complex composed of BAG6, transmembrane recognition complex 35 (TRC35) and ubiquitin-like protein 4A (UBL4A). The BAG6 complex together with the cochaperone small, glutamine-rich, tetratricopeptide repeat-containing, protein alpha (SGTA) plays a role in the biogenesis of tail-anchored membrane proteins and subsequently shown to regulate the ubiquitination and proteasomal degradation of mislocalized proteins. Moreover, BAG6 acts as an apoptotic regulator that binds reaper, a potent apoptotic inducer. BAG6/reaper is thought to signal apoptosis, in part through regulating the folding and activity of apoptotic signaling molecules. It is also likely a key regulator of the molecular chaperone Heat Shock Protein A2 (HSPA2) stability/function in human germ cells. Furthermore, aspartyl protease-mediated cleavage of BAG6 is necessary for autophagy and fungal resistance in plants. BAG6 contains a ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, which provides a platform for discriminating substrates with shorter hydrophobicity stretches as a signal for defective proteins.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIG 62
Cdd:cd01809   1 LEVTVKTLDSQNRTFTVPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVD 62

ubiquitin-like (Ubl) domain 1 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 (Ubl) that upon viral infection, modifies cellular and viral proteins by mechanisms similar to ubiquitination. Although ISG15 has properties similar to those of other 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 first Ubl domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFK--GKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01792   1 WDLTVKMLTGNEFQVSVSPSMTVSELKAQITQKIGVPAFQQRLAVQpsGVELQDGVRLASQGLGPSSTVLLVVK 74

ubiquitin-like (Ubl) domain found in ubiquitin-like PHD and RING finger domain-containing proteins, UHRF1 and UHRF2, and similar proteins; UHRF1 is a unique chromatin effector protein that integrates the recognition of both histone PTMs and DNA methylation. It is essential for cell proliferation and plays a critical role in the development and progression of many human carcinomas, such as laryngeal squamous cell carcinoma, gastric cancer, esophageal squamous cell carcinoma, colorectal cancer, prostate cancer, and breast cancer. UHRF1 can acts as a transcriptional repressor through its binding to histone H3 when it is unmodified at Arg2. Its overexpression in human lung fibroblasts results in downregulation of expression of the tumor suppressor pRB. It also plays a role in transcriptional repression of the cell cycle regulator p21. Moreover, UHRF1-dependent repression of factors can facilitate the G1-S transition. It interacts with Tat-interacting protein of 60 kDa (TIP60) and induces degradation-independent ubiquitination of TIP60. It is also an N-methylpurine DNA glycosylase (MPG)-interacting protein that binds MPG in a p53 status-independent manner in the DNA base excision repair (BER) pathway. In addition, UHRF1 functions as an epigenetic regulator that is important for multiple aspects of epigenetic regulation, including maintenance of DNA methylation patterns and recognition of various histone modifications. UHRF2 was originally identified as a ubiquitin ligase acting as a small ubiquitin-like modifier (SUMO) E3 ligase that enhances zinc finger protein 131 (ZNF131) SUMOylation but does not enhance ZNF131 ubiquitination. It also ubiquitinates PCNP, a PEST-containing nuclear protein. Moreover, UHRF2 functions as a nuclear protein involved in cell-cycle regulation and has been implicated in tumorigenesis. It interacts with cyclins, CDKs, p53, pRB, PCNA, HDAC1, DNMTs, G9a, methylated histone H3 lysine 9, and methylated DNA. It interacts with the cyclin E-CDK2 complex, ubiquitinates cyclins D1 and E1, induces G1 arrest, and is involved in the G1/S transition regulation. Furthermore, UHRF2 is a direct transcriptional target of the transcription factor E2F-1 in the induction of apoptosis. It recruits HDAC1 and binds to methyl-CpG. UHRF2 also participates in the maturation of Hepatitis B virus (HBV) through interacting with HBV core protein and promoting its degradation. Both UHRF1 and UHRF2 contain an N-terminal ubiquitin-like domain (Ubl), a tandem Tudor domain (TTD), a plant homeodomain (PHD) finger, a set- and ring-associated (SRA) domain, and a C-terminal RING finger.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 7657667    1 MQLTVKALQGRECSLQVPEDEL--VSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01797   1 MWIQVRTMDGKKEARVDGLSKLtkIEDLRERIEEKFDVEPELQRLFYRGKQLEDGHTLFDYDVGLNDIIQLMVR 74

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNS 65
Cdd:cd01810   1 LSIFVRNEKGQSHTYEVRLTQTVDQLKQKVSGREGVHDDQFWLTFEGRPLEDQLPLGEYGLKPQS 65

ubiquitin-like (Ubl) domain found in midnolin and similar proteins; Midnolin, also termed midbrain nucleolar protein, is a nucleolar protein that may be involved in regulation of genes related to neurogenesis in the nucleolus. It is strongly expressed at the mesencephalon (midbrain) of the embryo in day 12.5 (E12.5) mice and its expression is developmentally regulated. Midnolin plays a role in cellular signaling of adult tissues and regulates glucokinase enzyme activity in pancreatic beta cells. It can also control development via regulation of mRNA transport in cells. Midnolin contains an N-terminal conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKrLSDYSIGPNSKLNLV 70
Cdd:cd01804   1 INLYIHPTTGGRFELSVPPNETVEGLKRRISKKLKVPKERITLLHKEKQLKDGT-LRENGIGDGSKLTLL 69

Ubiquitin-2 like Rad60 SUMO-like; The small ubiquitin-related modifier SUMO-1 is a Ub/Ubl family member, and although SUMO-1 shares structural similarity to Ub, SUMO's cellular functions remain distinct insomuch as SUMO modification alters protein function through changes in activity, cellular localization, or by protecting substrates from ubiquitination. Rad60 family members contain functionally enigmatic, integral SUMO-like domains (SLDs). Despite their divergence from SUMO, each Rad60 SLD interacts with a subset of SUMO pathway enzymes: SLD2 specifically binds the SUMO E2 conjugating enzyme (Ubc9)), whereas SLD1 binds the SUMO E1 (Fub2, also called Uba2) activating and E3 (Pli1, also called Siz1 and Siz2) specificity enzymes. Structural analysis of PDB:2uyz reveals a mechanistic basis for the near-synonymous roles of Rad60 and SUMO in survival of genotoxic stress and suggest unprecedented DNA-damage-response functions for SLDs in regulating SUMOylation. The Rad60 branch of this family is also known as RENi (Rad60-Esc2-Nip45), and biologically it should be two distinct families SUMO and RENi (Rad60-Esc2-Nip45).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 7657667      1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQ-RLLFKGKALADGKRLSDYSI 61
Cdd:pfam11976   1 IKIILKGKDGKEVFIKVKPTTTVSKLINAYRKKRGIPPSQQvRLIFDGERLDPNSTVEDLDI 62

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        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657667    3 LTVKALQGREcSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01808   5 VTVKTPKEKE-DFEVPEDSSVKEFKEEISKKFKAPVEQLVLIFAGKILKDQDTLSQHGIKDGLTVHLVIK 73

ubiquitin-like (Ubl) domain found in Arabidopsis thaliana ubiquitin-protein ligase 5 (AtUPL5) and similar proteins; Arabidopsis thaliana AtUPL5, also termed HECT-type E3 ubiquitin transferase UPL5, is an E3 ubiquitin-protein ligase that contains a ubiquitin-like domain (Ubl), a C-type lectin-binding domain, a leucine zipper and a HECT domain. HECT domain containing-ubiquitin-protein ligases have more than one member in different genomes, these proteins have been classified into four sub-families (UPL1/2, UPL3/4, UPL5 and UPL6/7). AtUPL5 fUPL5 regulates leaf senescence in Arabidopsis through degradation of the transcription factor WRKY53.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 7657667    2 QLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLV 70
Cdd:cd16107   1 QIFVRTYCGKTIVLHAKASDTVESLHQQIEARTGIPSLEQRLIFGGRQLQHSQSLESCKMENDATLFLV 69

ubiquitin-like (Ubl) domain 2 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 second Ubl domain of FAT10. Some family members contain only one Ubl domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADG-KRLSDYSIGPNSKLNLV 70
Cdd:cd17053   1 LTVNSKLLTGTVHTLQVSRSTTVAQVKAMIEDQSGVPPNEQILVYNGKRLEDGdKTLGEYGIKTGDTLYLL 71

ubiquitin-like (Ubl) domain found in BAG family molecular chaperone regulator 1 (BAG1) and similar proteins; BAG1, also termed Bcl-2-associated athanogene 1, or HAP, is a multifunctional protein involved in a variety of cellular functions such as apoptosis, transcription, and proliferative pathways, as well as in cell signaling and differentiation. It delivers chaperone-recognized unfolded substrates to the proteasome for degradation. BAG1 functions as a co-chaperone for Hsp70/Hsc70 to increase Hsp70 foldase activity. It also suppresses apoptosis and enhances neuronal differentiation. As an anti-apoptotic factor, BAG1 interacts with tau and regulates its proteasomal degradation. It also binds to BCR-ABL with a high affinity, and directly routes immature BCR-ABL for proteasomal degradation. It acts as a potential therapeutic target in Parkinson's disease. It also modulates huntingtin toxicity, aggregation, degradation, and subcellular distribution, suggesting a role in Huntington's disease. There are at least four isoforms of Bag1 protein that are formed by alternative initiation of translation within a common mRNA. BAG1 contains an N-terminal ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, and a C-terminal BAG domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 7657667   18 PEDELVSTLKQL---VSEKLNVPVRQQRLLFKGKALAD-GKRLSDYSIGPNSKLNLVVK 72
Cdd:cd01812  18 SQDEDEPTLQDLaeaIEEVTGVPVENQKLIFKGKSLKDpEQPLSALGVKNGSKIMLIGK 76

ubiquitin-like (Ubl) domain found in NEDD8 ultimate buster 1 (NUB1) and similar proteins; NUB1, also termed negative regulator of ubiquitin-like proteins 1, or renal carcinoma antigen NY-REN-18, or protein BS4, is a NEDD8-interacting protein that can be induced by interferon. It functions as a strong post-transcriptional down-regulator of the NEDD8 expression and plays critical roles in regulating many biological events, such as cell growth, NF-kappaB signaling, and biological responses to hypoxia. NUB1 can also interact with aryl hydrocarbon receptor-interacting protein-like 1 (AIPL1), which may function in the regulation of cell cycle progression. NUB1 contains a conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, three ubiquitin-associated domains (UBA), a bipartite nuclear localization signal (NLS) and a PEST motif.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 7657667   12 ECSLqvpeDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKL 67
Cdd:cd17062  22 ETSL----DITGSELREKIAEELGVPEDRIKLISNGKVLKDEKTLAEQGVKNNSQV 73

ubiquitin-like (Ubl) domain found in parkin and similar proteins; Parkin, also termed Parkinson juvenile disease protein 2, is a RBR-type E3 ubiquitin-protein ligase that is associated with recessive early onset Parkinson's disease (PD), and exerts a protective effect against dopamine-induced alpha-synuclein-dependent cell toxicity. Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism. Parkin functions within a multiprotein E3 ubiquitin ligase complex, catalyzing the covalent attachment of ubiquitin moieties onto substrate proteins, such as BCL2, SYT11, CCNE1, GPR37, RHOT1/MIRO1, MFN1, MFN2, STUB1, SNCAIP, SEPT5, TOMM20, USP30, ZNF746 and AIMP2. It mediates monoubiquitination as well as Lys-6-, Lys-11-, Lys-48- and Lys-63-linked polyubiquitination of substrates depending on the context. Parkin may enhance cell viability and protects dopaminergic neurons from oxidative stress-mediated death by regulating mitochondrial function. It also limits the production of reactive oxygen species (ROS), and regulates cyclin-E during neuronal apoptosis. Moreover, parkin displays a ubiquitin ligase-independent function in transcriptional repression of p53. Parkin contains an N-terminal ubiquitin-like (Ubl) domain and a C-terminal RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain use an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction.

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gi 7657667   15 LQVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSDYSIGPNSKLNLV 70
Cdd:cd01798  13 VEVDSDWSILQLKEVVAKRQGVPPDQLRIIFAGKELSDDLTLQNCDLGQQSIVHAV 68

ubiquitin-like (Ubl) domain 1 found in FAS-associated factor 1 (FAF1) and similar proteins; FAF1, also termed UBX domain-containing protein 12 (UBXD12), or UBX domain-containing protein 3A (UBXN3A), belongs to the UBXD family of proteins that contains the ubiquitin (Ub) regulatory domain X (UBX) with a beta-grasp ubiquitin-like (Ubl) fold, but without the C-terminal double glycine motif. The UBX domain is typically located at the carboxyl terminus of proteins, and participates broadly in the regulation of protein degradation. In addition, FAF1 contains two tandem Ubl domains, which show high structural similarity with the UBX domain. FAF1 functions as a cofactor of p97 (also known as VCP or Cdc48), which is a homohexameric AAA ATPase (ATPase associated with a variety of activities) involved in a variety of functions ranging from cell-cycle regulation to membrane fusion and protein degradation. The FAF1-p97 complex inhibits the proteasomal protein degradation in which p97 acts as a co-chaperone. Moreover, FAF1 is an apoptotic signaling molecule that acts downstream in the Fas signal transduction pathway. It interacts with the cytoplasmic domain of Fas, but not to a Fas mutant that is deficient in signal transduction. FAF1 is widely expressed in adult and embryonic tissues, and in tumor cell lines, and is localized not only in the cytoplasm where it interacts with Fas, but also in the nucleus. FAF1 contains phosphorylation sites for protein kinase CK2 within the nuclear targeting domain. Phosphorylation influences nuclear localization of FAF1 but does not affect its potentiation of Fas-induced apoptosis. Other functions have also been attributed to FAF1. It inhibits nuclear factor-kappaB (NF-kappaB) by interfering with the nuclear translocation of the p65 subunit. Although the precise role of FAF1 in the ubiquitination pathway remains unclear, FAF1 interacts with valosin-containing protein (VCP), which is involved in the ubiquitin-proteosome pathway. The family corresponds to the first Ubl domain.

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gi 7657667   11 RECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLL-FKGKALADGKRLSDYSIGPNSKLNLV 70
Cdd:cd17129  11 RTIDVVLPDTETVGDIKQILENELGIPPCKQILKgWKARTVSDSTVLRSLHLPKENSLYLL 71

ubiquitin-like (Ubl) domain 1 found in 2'-5'-oligoadenylate synthase-like protein (OASL) and similar proteins; OASL, also termed 2'-5'-OAS-related protein (2'-5'-OAS-RP), or 59 kDa 2'-5'-oligoadenylate synthase-like protein, or thyroid receptor-interacting protein 14, or TR-interacting protein 14 (TRIP-14), or p59 OASL (p59OASL), is an interferon (IFN)-induced antiviral protein that plays an important role in the IFNs-mediated antiviral signaling pathway. It inhibits respiratory syncytial virus replication and is targeted by the viral nonstructural protein 1 (NS1). It also displays antiviral activity against encephalomyocarditis virus (EMCV) and hepatitis C virus (HCV) via an alternative antiviral pathway independent of RNase L. Moreover, OASL does not have 2'-5'-OAS activity, but can bind double-stranded RNA (dsRNA) to enhance RIG-I signaling. OASL belongs to the 2'-5' oligoadenylate synthase (OAS) family. While each member of this family has a conserved N-terminal OAS catalytic domain, only OASL has two tandem C-terminal ubiquitin-like (Ubl) repeats, which is required for its antiviral activity. This family corresponds to the first Ubl domain.

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gi 7657667    1 MQLTVKALQGRECSLQVPEDELVSTLKQLVSEKLNVPVRQQRLLFK-----GKALADGKRLSDYSIGPNSKLNLV 70
Cdd:cd01811   1 IQVTVKQLGGKSLTLWVNPYDPIWQLKEEIEKEWCIPIYQQRLSFQepggeRQVLRNDKTLADYGIFYDTTILLL 75

ubiquitin-like (Ubl) domain found in Sacsin and similar proteins; Sacsin, also termed DnaJ homolog subfamily C member 29 (DNAJC29), is encoded by SACS gene that is highly expressed in the brain. Mutations in SACS can cause the neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix Saguenay (ARSACS) which is characterized by early-onset spastic ataxia. Sacsin is a modular protein that is localized on the mitochondrial surface and possibaly required for normal mitochondrial network organization. Sacsin knockdown resulted in a reduction in cells expressing plyglutamine-expanded ataxin-1, which correlated with a loss of cells with large nuclear ataxin-1 incusions. At the N-terminus, sacsin contains a ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, which can interact with the proteasome. At the C-terminus, sacsin harbors a protein-protein interaction J-domain followed by an higher eukaryotes and prokaryotes nucleotide-binding (HEPN) domain. The J-domain is typically associated with DnaJ-like co-chaperones involved in regulation of the Hsp70 heat shock system.

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gi 7657667   16 QVPEDELVSTLKQLVSEKLNVPVRQQRLLFKGKALADGKRLSD 58
Cdd:cd17049  18 EVPPSAAVRDIKELIYEETDFPVSEQQLWHNGKELSDWVKIGG 60