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 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVGGKVIHLVER 87
Cdd:cd01809      1 LEVTVKTLDSQNRTFTVPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVDGKVIHLVER 71

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 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVGGKVIHLVER 87
Cdd:cd01809      1 LEVTVKTLDSQNRTFTVPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVDGKVIHLVER 71

Ubiquitin family; This family contains a number of ubiquitin-like proteins: SUMO (smt3 homolog), Nedd8, Elongin B, Rub1, and Parkin. A number of them are thought to carry a distinctive five-residue motif termed the proteasome-interacting motif (PIM), which may have a biologically significant role in protein delivery to proteasomes and recruitment of proteasomes to transcription sites.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1731767326   19 VLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVG-GKVIHLVERAP 89
Cdd:pfam00240    1 ITVKTLDGKKITLEVDPTDTVLELKEKIAEKEGVPPEQQRLIYSGKVLEDDQTLGEYGIEdGSTIHLVLRQR 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        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVS---IPSEKQRLIYQGRVLQDDKKLQEYNV--GGKVIHLVER---- 87
Cdd:TIGR00601    1 MTLTFKTLQQQKFKIDMEPDETVKELKEKIEAEQGkdaYPVAQQKLIYSGKILSDDKTVKEYKIkeKDFVVVMVSKpktg 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|...
gi 1731767326   88 ----APPQTQLPSGASSGTGSASATHGG--APLPGTRGPGASV 124
Cdd:TIGR00601   81 tgkvAPPAATPTSAPTPTPSPPASPASGmsAAPASAVEEKSPS 123

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 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVGGKVIHLVER 87
Cdd:cd01809      1 LEVTVKTLDSQNRTFTVPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVDGKVIHLVER 71

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 1731767326   19 VLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVG-GKVIHLV 85
Cdd:cd17039      1 ITVKTLDGKTYTVEVDPDDTVADLKEKIEEKTGIPVEQQRLIYNGKELKDDKTLSDYGIKdGSTIHLV 68

ubiquitin-like (Ubl) domain found in Saccharomyces cerevisiae proteasome interacting protein Dsk2p and similar proteins; The family contains several fungal multiubiquitin receptors, including Saccharomyces cerevisiae Dsk2p and Schizosaccharomyces pombe Dph1p, both of which have been characterized as shuttle proteins transporting ubiquitinated substrates destined for degradation from the E3 ligase to the 26S proteasome. They interact with the proteasome through their N-terminal ubiquitin-like domain (Ubl) and with ubiquitin (Ub) through their C-terminal Ub-associated domain (UBA). S. cerevisiae Dsk2p is a nuclear-enriched protein that may involve in the ubiquitin-proteasome proteolytic pathway through interacting with K48-linked polyubiquitin and the proteasome. Moreover, it has been implicated in spindle pole duplication through assisting in Cdc31 assembly into the new spindle pole body (SPB). S. pombe Dph1p is an ubiquitin (Ub0 receptor working in concert with the class V myosin, Myo52, to target the degradation of the S. pombe CLIP-170 homolog, Tip1. It also can protect Ub chains against disassembly by deubiquitinating enzymes.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|..
gi 1731767326   38 NVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV-GGKVIHLVERA 88
Cdd:cd16106     22 TVLELKELIAEKSDIPAEQQRLIYKGKILKDEETLSSYKIqDGHTVHLVKGA 73

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 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV 77
Cdd:cd01810      1 LSIFVRNEKGQSHTYEVRLTQTVDQLKQKVSGREGVHDDQFWLTFEGRPLEDQLPLGEYGL 61

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 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVGGK-VIHLVER 87
Cdd:cd01803      1 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKEsTLHLVLR 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        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVS---IPSEKQRLIYQGRVLQDDKKLQEYNV--GGKVIHLVER---- 87
Cdd:TIGR00601    1 MTLTFKTLQQQKFKIDMEPDETVKELKEKIEAEQGkdaYPVAQQKLIYSGKILSDDKTVKEYKIkeKDFVVVMVSKpktg 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|...
gi 1731767326   88 ----APPQTQLPSGASSGTGSASATHGG--APLPGTRGPGASV 124
Cdd:TIGR00601   81 tgkvAPPAATPTSAPTPTPSPPASPASGmsAAPASAVEEKSPS 123

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.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASV---SIPSEKQRLIYQGRVLQDDKKLQEYNVGGK--VIHLVERA 88
Cdd:cd16126      1 MQITLKTLQQQTFKIDIDPEETVKALKEKIESEKgkdAFPVAGQKLIYAGKILNDDTALKEYKIDEKnfVVVMVTKP 77

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1731767326   19 VLVKTLDSQtRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV-GGKVIHLV 85
Cdd:cd01808      5 VTVKTPKEK-EDFEVPEDSSVKEFKEEISKKFKAPVEQLVLIFAGKILKDQDTLSQHGIkDGLTVHLV 71

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 1731767326   18 EVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV 77
Cdd:cd16107      1 QIFVRTYCGKTIVLHAKASDTVESLHQQIEARTGIPSLEQRLIFGGRQLQHSQSLESCKM 60

ubiquitin-like (Ubl) domain found in UV excision repair protein RAD23 homolog A (HR23A); HR23A, also termed RAD23A, is a DNA repair protein that binds to 19S subunit of the 26S proteasome and shuttles ubiquitinated proteins to the proteasome for degradation, which is required for efficient nucleotide excision repair (NER), a primary mechanism for removing UV-induced DNA lesions. HR23A also plays a critical role in the interaction of HIV-1 viral protein R (Vpr) with the proteasome, especially facilitating Vpr to promote protein poly-ubiquitination. HR23A 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.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASV---SIPSEKQRLIYQGRVLQDDKKLQEYNVGGK 80
Cdd:cd17126      1 VTITLKTLQQQTFKIRMEPDETVKVLKEKIEAEKgrdAFPVAGQKLIYAGKILSDDVPIRDYRIDEK 67

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 1731767326   21 VKTLDSQTRTFIVGAQ--MNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVG-GKVIHLVER 87
Cdd:cd01797      5 VRTMDGKKEARVDGLSklTKIEDLRERIEEKFDVEPELQRLFYRGKQLEDGHTLFDYDVGlNDIIQLMVR 74

Beta-grasp ubiquitin-like fold; Ubiquitin is a protein modifier that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. The ubiquitination process comprises 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 proteins have similar ubiquitin beta-grasp fold and attach to other proteins in a ubiquitin-like manner but with biochemically distinct roles. Ubiquitin and ubiquitin-like proteins conjugate and deconjugate via ligases and peptidases to covalently modify target polypeptides. Some other ubiquitin-like domains have adaptor roles in ubiquitin-signaling by mediating protein-protein interaction. In addition to Ubiquitin-like (Ubl) domain, Ras-associating (RA) domain, F0/F1 sub-domain of FERM (Four.1 protein, Ezrin, Radixin, Moesin) domain, TGS (ThrRS, GTPase and SpoT) domain, Ras-binding domain (RBD), Ubiquitin regulatory domain X (UBX), Dublecortin-like domain, and RING finger- and WD40-associated ubiquitin-like (RAWUL) domain have beta-grasp ubiquitin-like folds, and are included in this superfamily.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1731767326   19 VLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYN-VGGKVIHLV 85
Cdd:cd00196      1 VKVETPSLKKIVVAVPPSTTLRQVLEKVAKRIGLPPDVIRLLFNGQVLDDLMTAKQVGlEPGEELHFV 68

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
                   ....*....|....*....|....*....|....*....|....*...
gi 1731767326   40 KEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV--GGKVIHLV 85
Cdd:cd17062     30 SELREKIAEELGVPEDRIKLISNGKVLKDEKTLAEQGVknNSQVMVLV 77

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
                   ....*....|....*....|....*....|....*....|....*....|.
gi 1731767326   27 QTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV 77
Cdd:cd01793      9 SLHTLEVSGNETVADIKAHIAALEGIAVEDQVLLYAGAPLEDDVVLGQCGI 59

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 1731767326   17 LEVLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV-GGKVIHLV 85
Cdd:cd01802      1 MELFIETLTGTAFELRVSPFETVASVKAKIQRLEGIPVSQQHLIWSGRELEDDYCLHDYNItDGSTLKLV 70

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 1731767326   39 VKEFKEHIAASV-SIPSEK-QRLIYQGRVLQDDKKLQEY-----NVGGKVIHLV 85
Cdd:cd01790     25 VLKLKEHLSEVYpSKPLPEdQKLIYSGKLLEDHQTLKDVlreddPEQVHTVHLV 78

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.

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gi 1731767326   19 VLVKTLDSQTRTFIVGAQMNVKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNV 77
Cdd:cd16103      4 IFVKFPDGTSKPYAINPEDTILDLKEKIEEQGGPPVEDQILLFQGQELRDKKSLKYYGI 62

ubiquitin-like (Ubl) domain found in ubiquitin-like PHD and RING finger domain-containing protein 1(UHRF1); UHRF1, also termed inverted CCAAT box-binding protein of 90 kDa, or nuclear protein 95, or nuclear zinc finger protein Np95 (Np95), or RING finger protein 106, or transcription factor ICBP90, or E3 ubiquitin-protein ligase 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 ofTIP60. It is also an N-methylpurine DNA glycosylase (MPG)-interacting protein that binds MPG in a p53status-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. UHRF1 contains an N-terminal ubiquitin-like domain (Ubl), a tandem Tudor domain (TTD), a plant homeodomain (PHD) finger, a SET and RING finger associated (SRA) domain, and a C-terminal RING-finger domain. It specifically binds to hemimethylated DNA, double-stranded CpG dinucleotides, and recruits the maintenance methyltransferase DNMT1 to its hemimethylated DNA substrate through its SRA domain. UHRF1-dependent H3K23 ubiquitination has an essential role in maintenance DNA methylation and replication. The tandem Tudor domain directs UHRF1 binding to the heterochromatin mark histone H3K9me3 and the PHD finger targets UHRF1 to unmodified histone H3 in euchromatic regions. The RING-finger domain exhibits both autocatalytic E3 ubiquitin (Ub) ligase activity and activity against histone H3 and DNMT1.

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gi 1731767326   21 VKTLDS-QTRTFIVGAQMN-VKEFKEHIAASVSIPSEKQRLIYQGRVLQDDKKLQEYNVG-GKVIHLVER 87
Cdd:cd17122      5 VRTMDGkETHRIDSLSKLTkVEELRQKIQELFGVEPERQRLFYRGKQMEDGHTLFDYSVGlNDIVQLLVR 74