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 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:cd01803   1 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 76

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 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:cd01803   1 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 76

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 400261191    5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLR 76
Cdd:smart00213  1 IELTVKTLDGKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

ubiquitin; Provisional

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:PTZ00044  1 MQILIKTLTGKKQSFNFEPDNTVQQVKMALQEKEGIDVKQIRLIYSGKQMSDDLKLSDYKVVPGSTIHMVLQLRGG 76

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 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:cd01803   1 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 76

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 400261191    5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLR 76
Cdd:smart00213  1 IELTVKTLDGKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 400261191  7 IFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:cd01806   1 IKVKTLTGKEIEIDIEPTDKVERIKERVEEKEGIPPQQQRLIFSGKQMNDEKTAADYKIEGGSVLHLVLALRGG 74

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLR 78
Cdd:cd01802   1 MELFIETLTGTAFELRVSPFETVASVKAKIQRLEGIPVSQQHLIWSGRELEDDYCLHDYNITDGSTLKLVLAMR 74

ubiquitin; Provisional

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:PTZ00044  1 MQILIKTLTGKKQSFNFEPDNTVQQVKMALQEKEGIDVKQIRLIYSGKQMSDDLKLSDYKVVPGSTIHMVLQLRGG 76

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 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDG-RTLSDYNIQKESTLHLV 74
Cdd:cd17053   1 LTVNSKLLTGTVHTLQVSRSTTVAQVKAMIEDQSGVPPNEQILVYNGKRLEDGdKTLGEYGIKTGDTLYLL 71

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 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEG-IPPDQQRLIFAGKQLEDGRTLSDYNIQKESTL 71
Cdd:cd01805   1 MKITFKTLQQQTFEIEVEPSDTVLELKEKIEQEQGdFPASGQKLIYSGKVLKDDKTLSEYNIKEKDFV 68

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 400261191  5 MQIFVKTltGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLRLRGG 80
Cdd:cd01793   1 MQLFVRA--QSLHTLEVSGNETVADIKAHIAALEGIAVEDQVLLYAGAPLEDDVVLGQCGIPDLATLEVAVRLLGG 74

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 400261191  7 IFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLR 76
Cdd:cd01798   1 VFVRFNSSHGFPVEVDSDWSILQLKEVVAKRQGVPPDQLRIIFAGKELSDDLTLQNCDLGQQSIVHAVQG 70

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQkESTLHLVLR 76
Cdd:cd01809   1 LEVTVKTLDSQNRTFTVPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVD-GKVIHLVER 71

ubiquitin-like (Ubl) domain 2 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 are required for its antiviral activity. This family corresponds to the second Ubl domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 400261191  4 GMQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVL 75
Cdd:cd16103   1 EIQIFVKFPDGTSKPYAINPEDTILDLKEKIEEQGGPPVEDQILLFQGQELRDKKSLKYYGIKDGDTLQLSL 72

UV excision repair protein Rad23; All proteins in this family for which functions are known are components of a multiprotein complex used for targeting nucleotide excision repair to specific parts of the genome. In humans, Rad23 complexes with the XPC protein. This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 400261191    5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEG---IPPDQQRLIFAGKQLEDGRTLSDYNI 65
Cdd:TIGR00601   1 MTLTFKTLQQQKFKIDMEPDETVKELKEKIEAEQGkdaYPVAQQKLIYSGKILSDDKTVKEYKI 64

ubiquitin-like (Ubl) domain found in the eukaryotic Ddi1 family; The eukaryotic Ddi1 family, including yeast aspartyl protease DNA-damage inducible 1 (Ddi1) and Ddi1-like proteins from vertebrates and other eukaryotes, has been characterized by containing an N-terminal ubiquitin-like (Ubl) domain and a conserved retroviral aspartyl-protease-like domain (RVP) that is important in cell-cycle control. Yeast Ddi1 and many family members also contain a C-terminal ubiquitin-association (UBA) domain, however, Ddi1-like proteins from all vertebrates lack the UBA domain. Ddi1, also termed v-SNARE-master 1 (Vsm1), is an ubiquitin receptor involved in the cell cycle and late secretory pathway in Saccharomyces cerevisiae. It functions as an UBA-Ubl shuttle protein that is required for the proteasome to enable ubiquitin-dependent degradation of its ligands. For instance, Ddi1 plays an essential role in the final stages of proteasomal degradation of Ho endonuclease and of its cognate FBP, Ufo1. Moreover, Ddi1 and its associated protein Rad23p play a cooperative role as negative regulators in yeast PHO pathway. This family also includes mammalian regulatory solute carrier protein family 1 member 1 (RSC1A1), also termed transporter regulator RS1 (RS1), which mediates transcriptional and post-transcriptional regulation of Na(+)-D-glucose cotransporter SGLT1. Ddi1-like proteins play a significant role in cell cycle control, growth control, and trafficking in yeast and may play a crucial role in embryogenesis in higher eukaryotes.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 400261191  5 MQIFVKTL-TGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQL-EDGRTLSDYNIQ 66
Cdd:cd01796   1 MKLTVTTEdDDRLFSLEVSPDMTLEDLKALCEAETGIPAAEQVLLHNGQPLtDDKKTLEALGLK 64

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 400261191  5 MQIFVKTLTGK--TITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLR 76
Cdd:cd01797   1 MWIQVRTMDGKkeARVDGLSKLTKIEDLRERIEEKFDVEPELQRLFYRGKQLEDGHTLFDYDVGLNDIIQLMVR 74

ubiquitin-like (Ubl) domain found in splicing factor 3A 120kDa subunit (SF3a120) and similar proteins; Mammalian splicing factor SF3a consists of three subunits of 60, 66, and 120 kDa and functions early during pre-mRNA splicing by converting the U2 snRNP to its active form. The 120kDa subunit SF3a120, also termed splicing factor 3A subunit 1 (SF3A1), or spliceosome-associated protein 114 (SAP114), is the U2 snRNP-specific protein that is critical for spliceosome assembly and normal splicing events. During splicing, SF3a120, together with the U2 snRNP and other proteins, are recruited to the 3' splicing site to generate the splicing complex A after the recognition of the 3' splicing site. SF3a120 contains two N-terminal SWAP (suppressor-of-white-apricot) domains, referred to collectively as the SURP module, as well as a C-terminal ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 400261191 12 LTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRL-IFAGKQLEDGRTLSDYNIQKESTLHLVLR 76
Cdd:cd01800  19 LNGQVLELTLPLTDTISVLKEKIHEELGMPANKQKLqVEGGGFLKDSNSLAFYNLGSGTVLTLSLK 84

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIF---AGKQ--LEDGRTLSDYNIQKESTLHLV 74
Cdd:cd01811   1 IQVTVKQLGGKSLTLWVNPYDPIWQLKEEIEKEWCIPIYQQRLSFqepGGERqvLRNDKTLADYGIFYDTTILLL 75

ubiquitin-like (Ubl) domain found in ubiquitin domain-containing protein 1 (UBTD1); UBTD1 is the mammalian homolog of the mitochondrial Dc-UbP/UBTD2 protein, both of which contain an N-terminal ubiquitin binding domain (UBD) and a C-terminal ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions. UBTD1 stably interacts with the UBE2D family of E2 ubiquitin conjugating enzymes. As a tumor suppressor, UBTD1 plays a pivotal role in in regulating cellular senescence that mediates p53 function. It is also involved in MDM2 ubiquitination and degradation.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 400261191  9 VKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVL 75
Cdd:cd17120   3 VRLSTGKDVRLSASMSDTIGQLKKQLHAQEGIEPSWQRWFFSGKLLTDKTRLQETKIQKDFVIQVIV 69

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 400261191 15 KTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLI-FAGKQLEDGRTLSDYNIQKESTLHLV 74
Cdd:cd17129  11 RTIDVVLPDTETVGDIKQILENELGIPPCKQILKgWKARTVSDSTVLRSLHLPKENSLYLL 71

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.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGrTLSDYNIQKESTLHLV 74
Cdd:cd01804   1 INLYIHPTTGGRFELSVPPNETVEGLKRRISKKLKVPKERITLLHKEKQLKDG-TLRENGIGDGSKLTLL 69

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 400261191 13 TGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGR-TLSDYNIQKESTLHLV 74
Cdd:cd01795   4 RGERKSLTVSSTTTLKELKLQIMEKFSVAPFDQHLYFNGRELTDDSaTLADLGILPGDVLYLK 66

ubiquitin-like (Ubl) domain found in UV excision repair protein RAD23 homolog B (HR23B); HR23B, also termed xeroderma pigmentosum group C (XPC) repair-complementing complex 58 kDa protein (p58), is tightly complexed with XPC protein to form the XPC-HR23B complex. Although it displays a high affinity for both single- and double-stranded DNA, the XPC-HR23B complex functions as a global genome repair (GGR)-specific repair factor that is specifically involved in global genome but not transcription-coupled nucleotide excision repair (NER). HR23B also interacts specifically with S5a subunit of the human 26S proteasome, and plays an important role in shuttling ubiquitinated cargo proteins to the proteasome. HR23B contains an N-terminal ubiquitin-like (Ubl) domain that binds proteasomes and two C-terminal ubiquitin-associated (UBA) domains that bind ubiquitin or multi-ubiquitinated substrates. In addition, it has a XPC protein-binding domain that might be necessary for its efficient NER function.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEG---IPPDQQRLIFAGKQLEDGRTLSDYNIQKES 69
Cdd:cd16126   1 MQITLKTLQQQTFKIDIDPEETVKALKEKIESEKGkdaFPVAGQKLIYAGKILNDDTALKEYKIDEKN 68

ubiquitin-like (Ubl) domain found in homocysteine-inducible endoplasmic reticulum stress protein HERP; HERP is an endoplasmic reticulum (ER) integral membrane protein containing an N-terminal ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold. The Ubl domain is required for the degradation of HERP itself as well as for HERP-mediated anti-apoptotic effects. HERP is induced by the ER stress response pathway and is involved in improving the balance of folding capacity and protein loads in the ER. There are two types of HERP, HERP1 and HERP2, which are encoded by the HERPUD1 and HERPUD2 genes, respectively.

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                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 400261191 18 TLEVEPSDTIENVKAKIQDK-EGIP-PDQQRLIFAGKQLEDGRTLSDYNIQKES----TLHLV 74
Cdd:cd01790  16 TVNCTLGWTVLKLKEHLSEVyPSKPlPEDQKLIYSGKLLEDHQTLKDVLREDDPeqvhTVHLV 78

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.

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                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 400261191 17 ITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLhLVLRL 77
Cdd:cd17062  19 ITLETSLDITGSELREKIAEELGVPEDRIKLISNGKVLKDEKTLAEQGVKNNSQV-MVLVL 78

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 400261191  15 KTITLEVEPSDTIENVKAKIqdkEGI---PPDQQRLIFAGKQLEDGRTLSDYNI-------QKESTLHLVLRLRGG 80
Cdd:cd01788   11 TTIFTDAKESTTVFELKKII---EGIlkrPPEDQRLYKDDQLLDDTKTLGDCGFtsqtaraQAPATLGLAFRADGE 83

ubiquitin-like (Ubl) domain found in ubiquitin-like domain-containing CTD phosphatase 1 (UBLCP1) and similar proteins; UBLCP1 is a 26S proteasome phosphatase that regulates nuclear proteasome activity. It is localized in the nucleus and it contains conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, which directly interacts with the proteasome. Knockdown of UBLCP1 in cells promotes 26S proteasome assembly and selectively enhances nuclear proteasome activity. UBLCP1 may also play a role in the regulation of phosphorylation state of RNA polymerase II C-terminal domain, a key event during mRNA metabolism.

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                ....*....|....*....|....*....|....*....|....*....|....*.
gi 400261191 14 GKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLI---FAGKQLEDGRTLSDYNIQ 66
Cdd:cd01813   9 GKEYPVTVLSSDTVLDLKQRIFELTGVLPKRQKLLglkVKGKPADDDVKLSSLKLK 64

ubiquitin-like (Ubl) domain found in ubiquitin domain-containing protein UBFD1 and similar proteins; UBFD1, also termed ubiquitin-binding protein homolog (UBPH), is a polyubiquitin binding protein containing a conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions. It may play a role as nuclear factor-kappaB (NF-kappaB) regulator.

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                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 400261191 15 KTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGkQLEDGRTLSDYNIQKESTLHLV 74
Cdd:cd17047  10 EKYDVKFPLDSTIAELKEHIETLTGVPPAMQKLMYKG-LLKDDKTLRELKVTKGAKVMVV 68

Ubiquitin-2 like Rad60 SUMO-like;

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 400261191   22 EPSDTIENVKAKI-----QDKEGIPPDQQ--RLIFAGKQLEDGRTLSDYNI------QKESTLHLVLR 76
Cdd:pfam13881  21 SPATTVADLKEKViaqwpKDKENGPKTVNdvKLINAGKILENNKTLGECRLpvgetpGGVTTMHVVVR 88

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.

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                ....*....|....*....|....*....|....*....|....*....|..
gi 400261191 13 TGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFA-GKQLEDGRTLSDY 63
Cdd:cd17046  10 TYRILSYEVTEDTSLSTLQSWIERDTGIPVEDQELLLPtGVSLDPEKPASQC 61

ubiquitin-like (Ubl) domain found in Arabidopsis thaliana NPL4-like proteins NPL4-1, NPL4-2, and similar proteins; The family includes a group of uncharacterized plant ubiquitin-like (Ubl) domain-containing proteins, including Arabidopsis thaliana NPL4-like protein 1 and NPL4-like protein 2.

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                ....*....|....*....|....*....|....*....|....*....|....*....
gi 400261191 19 LEVEPSDTIENVKAKIQDKEGIPPDQQRL-IFAGKQL---EDGRTLSDYNIQKESTLHL 73
Cdd:cd17055  14 VEVPDDATVGDLKEKIAEQLSVPVSDQTLsLDPGPDLltaKSSATLSQLGLKHGDMVFL 72

ubiquitin-like (Ubl) domain found in ubiquitin-like protein 5 (UBL5) and similar proteins; UBL5, known as Hub1 in yeast, is an atypical ubiquitin-like (Ubl) post-translational modifier that contains a conserved Ubl domain with a beta-grasp Ubl fold. At the C-terminal end of its Ubl fold is a di-tyrosine motif followed by a single variable residue instead of the characteristic di-glycine found in all other Ubl modifiers, and thus UBL5 does not form covalent conjugates with cellular proteins. The yeast Hub1p binds non-covalently to the HIND element of spliceosomal protein Snu66p (Snu66p is termed SART1 in mammals) and modifies the spliceosome by this unconventional Ubl modifier. In higher eukaryotes, UBL5/Hub1 plays a role in modulating pre-mRNA splicing. It also is required for signaling in the mitochondrial unfolded protein response, through interaction with the transcription factor DVE-1 and upregulation of chaperone genes in response to mitochondrial stress. Moreover, UBL5 functions as a factor that directly binds to and stabilizes FANCI, and promotes the functionality of the Fanconi anemia (FA) DNA repair pathway.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 400261191  5 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHL 73
Cdd:cd01791   2 IEVICNDRLGKKVRVKCNPDDTIGDLKKLIAAQTGTRPEKIVLKKWYTIFKDHITLEDYEIHDGMNLEL 70

ubiquitin-like (Ubl) domain 2 found in Ankyrin repeat and ubiquitin domain-containing 1 (ANKUB1) and similar proteins; ANKUB1 is an uncharacterized protein with two tandem ubiquitin-like (Ubl) domains located at the N-terminal of Ankyrin repeats (ANK). The Ubl domain may have an adaptor role in ubiquitin(Ub)-signaling by mediating protein-protein interaction. Ubl proteins have a beta-grasp Ubl fold and attach to other proteins in a Ubl manner with biochemically distinct roles. The ankyrin repeats have been identified in numerous proteins with diverse functions. The family corresponds to the second Ubl domain.

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                ....*....|....*....|....*....|....*....|....*....|..
gi 400261191 23 PSDTIENVKAKIQDKEGIPPDQQRLI-FAGKQLEDGRTLSDYNIQKESTLHL 73
Cdd:cd17051  26 LTTTVSQLRSIISRKTGLPVSVFRLVtPDGTEMYDCNLLDDYGIDIGTTLRL 77

ubiquitin-like (Ubl) domain found in small ubiquitin-related modifier (SUMO) and similar proteins; SUMO (also known as "Smt3" and "sentrin" in other organisms) resembles ubiquitin (Ub) in structure, ligation to other proteins, and the mechanism of ligation. 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 Ub and the epsilon-amino group of a substrate lysine. SUMOs, like Ub, are covalently conjugated to lysine residues in a wide variety of target proteins in eukaryotic cells and regulate numerous cellular processes, such as transcription, epigenetic gene control, genomic instability, and protein degradation. The mammalian SUMOs have four paralogs, SUMO1 through SUMO4, which all regulate different cellular functions by conjugating to different proteins. SUMO2-4 are more closely related to each other than to SUMO1.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 400261191 13 TGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQ 66
Cdd:cd01763  11 GGKKVRFKVKKTTKLKKLFDAYAEKKGLDPDSLRFTFDGERISPNDTPESLGLE 64

Ubiquitin regulatory domain X (UBX) structurally similar to a beta-grasp ubiquitin-like fold; The UBXD family of proteins contains the ubiquitin regulatory domain X (UBX) with a beta-grasp ubiquitin-like fold, but without the C-terminal double glycine motif. UBX domain is typically located at the carboxyl terminus of proteins, and participates broadly in the regulation of protein degradation. Members in this family function as cofactors 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. Based on domain composition, UBXD proteins can be divided into two main groups, with and without ubiquitin-associated (UBA) domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 400261191  9 VKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAG-----KQLEDGRTLSDYNIQKESTLHLV 74
Cdd:cd01767   4 IRLPDGSRIQRRFSKSDTLQDLYDFVESNLGDSPSSFSLVTSFprrvlTDEDSDKTLEELGLTPNAVLFVE 74