B-Box C-terminal domain; Coiled coil region C-terminal to (some) B-Box domains

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091  132 LAEIYEQHVTKVNEEVAKLRRRLMELISLVQEVERNVEAVRNAKDERVREIRNAVE----MMIARLDTQLKNKLITLMGQ 207
Cdd:smart00502   1 QREALEELLTKLRKKAAELEDALKQLISIIQEVEENAADVEAQIKAAFDELRNALNkrkkQLLEDLEEQKENKLKVLEQQ 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*..
gi 1005261091  208 KTSLTQETELLESLLQEVEHQLRSCSKSELISKSSEILMMFQQVHRK 254
Cdd:smart00502  81 LESLTQKQEKLSHAINFTEEALNSGDPTELLLSKKLIIERLQNLLKQ 127

Modified RING finger, HC subclass (C4C4-type), found in tripartite motif-containing protein 37 (TRIM37) and similar proteins; TRIM37, also known as mulibrey nanism protein, or MUL, is a peroxisomal E3 ubiquitin-protein ligase that is involved in the tumorigenesis of several cancer types, including pancreatic ductal adenocarcinoma (PDAC), hepatocellular carcinoma (HCC), breast cancer, and sporadic fibrothecoma. It mono-ubiquitinates histone H2A, a chromatin modification associated with transcriptional repression. Moreover, TRIM37 possesses anti-HIV-1 activity, and interferes with viral DNA synthesis. Mutations in the human TRIM37 gene (also known as MUL) cause Mulibrey (muscle-liver-brain-eye) nanism, a rare growth disorder of prenatal onset characterized by dysmorphic features, pericardial constriction, and hepatomegaly. TRIM37 belongs to the C-VIII subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a MATH (meprin and TRAF-C homology) domain positioned C-terminal to the RBCC domain. Its MATH domain has been shown to interact with the TRAF (TNF-Receptor-Associated Factor) domain of six known TRAFs in vitro.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1005261091  13 FRCFICMEKLRDARLCPHCSKLCCFSCIRRWLTEQRAQCPHCR 55
Cdd:cd16619     1 FRCFICMEKLRDPRLCPHCSKLFCKGCIRRWLSEQRSSCPHCR 43

B-Box C-terminal domain; Coiled coil region C-terminal to (some) B-Box domains

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091  132 LAEIYEQHVTKVNEEVAKLRRRLMELISLVQEVERNVEAVRNAKDERVREIRNAVE----MMIARLDTQLKNKLITLMGQ 207
Cdd:smart00502   1 QREALEELLTKLRKKAAELEDALKQLISIIQEVEENAADVEAQIKAAFDELRNALNkrkkQLLEDLEEQKENKLKVLEQQ 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*..
gi 1005261091  208 KTSLTQETELLESLLQEVEHQLRSCSKSELISKSSEILMMFQQVHRK 254
Cdd:smart00502  81 LESLTQKQEKLSHAINFTEEALNSGDPTELLLSKKLIIERLQNLLKQ 127

Modified RING finger, HC subclass (C4C4-type), found in tripartite motif-containing protein 37 (TRIM37) and similar proteins; TRIM37, also known as mulibrey nanism protein, or MUL, is a peroxisomal E3 ubiquitin-protein ligase that is involved in the tumorigenesis of several cancer types, including pancreatic ductal adenocarcinoma (PDAC), hepatocellular carcinoma (HCC), breast cancer, and sporadic fibrothecoma. It mono-ubiquitinates histone H2A, a chromatin modification associated with transcriptional repression. Moreover, TRIM37 possesses anti-HIV-1 activity, and interferes with viral DNA synthesis. Mutations in the human TRIM37 gene (also known as MUL) cause Mulibrey (muscle-liver-brain-eye) nanism, a rare growth disorder of prenatal onset characterized by dysmorphic features, pericardial constriction, and hepatomegaly. TRIM37 belongs to the C-VIII subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a MATH (meprin and TRAF-C homology) domain positioned C-terminal to the RBCC domain. Its MATH domain has been shown to interact with the TRAF (TNF-Receptor-Associated Factor) domain of six known TRAFs in vitro.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1005261091  13 FRCFICMEKLRDARLCPHCSKLCCFSCIRRWLTEQRAQCPHCR 55
Cdd:cd16619     1 FRCFICMEKLRDPRLCPHCSKLFCKGCIRRWLSEQRSSCPHCR 43

B-box zinc finger;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1005261091  90 NEKDKCENHH-EKLSVFCWTCKKCICHQCALwgGMHGGHTFKPL 132
Cdd:pfam00643   1 SKERLCPEHEeEPLTLYCNDCQELLCEECSV--GEHRGHTVVPL 42

MATH domain; This motif has been called the Meprin And TRAF-Homology (MATH) domain. This domain is hugely expanded in the nematode C. elegans.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091 285 NFSTLRQRaDPVYSPPLQVSGLCWRLKVYPDGNgvvrgyYLSVFL----ELSAGLPETSKYEYRVEMVHQSCNDPTKNII 360
Cdd:pfam00917   3 NFSKIKEG-ESYYSPVEERFNIPWRLQIYRKGG------FLGLYLhcdkEEELERGWSIETEFTLKLVSSNGKSVTKTDT 75

                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 1005261091 361 REFASDfevgECWGYNRFFRLDLLANEgYLNpqNDTVI 398
Cdd:pfam00917  76 HVFEKP----KGWGWGKFISWDDLEKD-YLV--DDSIT 106

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1005261091  15 CFICMEKLRDARLCP--HCSklCCFSCIRRWLtEQRAQCPHCRAPLQ 59
Cdd:pfam13920   5 CVICLDRPRNVVLLPcgHLC--LCEECAERLL-RKKKKCPICRQPIE 48

DNA repair protein rad18; All proteins in this family for which functions are known are involved in nucleotide excision repair.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
                  ....*....|....*....|....*....|....*....|....*..
gi 1005261091  13 FRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQrAQCPHCRAPLQ 59
Cdd:TIGR00599  27 LRCHICKDFFDVPVLTS-CSHTFCSLCIRRCLSNQ-PKCPLCRAEDQ 71

The Bin/Amphiphysin/Rvs (BAR) domain of GTPase Regulator Associated with Focal adhesion kinase; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions. GTPase Regulator Associated with Focal adhesion kinase (GRAF), also called Rho GTPase activating protein 26 (ARHGAP26), is a GAP with activity towards RhoA and Cdc42 and is only weakly active towards Rac1. It influences Rho-mediated cytoskeletal rearrangements and binds focal adhesion kinase (FAK), which is a critical component of integrin signaling. GRAF contains an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, a Rho GAP domain, and a C-terminal SH3 domain. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. The BAR domain of GRAF directly interacts with its Rho GAP domain and inhibits its activity. Autoinhibited GRAF is capable of binding membranes and tubulating liposomes, showing that the membrane-tubulation and GAP-inhibitory functions of the BAR domain can occur simultaneously.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091 158 ISLVQEVERNVEAVRNAKDERVREIRNAVEMMIARLDTQLKNKLITLMGQKTSLTQETELL---------------ESLL 222
Cdd:cd07636    63 ICIARSLQEFAAVLRNLEDERTRMIENASEVLITPLEKFRKEQIGAAKEAKKKYDKETEKYcavlekhlnlsskkkESQL 142

                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 1005261091 223 QEVEHQLRSCsKSELISKSSEILMMFQQVHRKPMASFV 260
Cdd:cd07636   143 HEADSQVDLV-RQHFYEVSLEYVFKVQEVQERKMFEFV 179

B-Box C-terminal domain; Coiled coil region C-terminal to (some) B-Box domains

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091  132 LAEIYEQHVTKVNEEVAKLRRRLMELISLVQEVERNVEAVRNAKDERVREIRNAVE----MMIARLDTQLKNKLITLMGQ 207
Cdd:smart00502   1 QREALEELLTKLRKKAAELEDALKQLISIIQEVEENAADVEAQIKAAFDELRNALNkrkkQLLEDLEEQKENKLKVLEQQ 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*..
gi 1005261091  208 KTSLTQETELLESLLQEVEHQLRSCSKSELISKSSEILMMFQQVHRK 254
Cdd:smart00502  81 LESLTQKQEKLSHAINFTEEALNSGDPTELLLSKKLIIERLQNLLKQ 127

B-box-type 2 zinc finger found in tripartite motif-containing protein 37 (TRIM37) and similar proteins; TRIM37, also known as Mulibrey nanism protein, is a peroxisomal E3 ubiquitin-protein ligase that is involved in the tumorigenesis of several cancer types, including pancreatic ductal adenocarcinoma (PDAC), hepatocellular carcinoma (HCC), breast cancer, and sporadic fibrothecoma. It mono-ubiquitinates histone H2A, a chromatin modification associated with transcriptional repression. Moreover, TRIM37 possesses anti-HIV-1 activity, and interferes with viral DNA synthesis. Mutations in the human TRIM37 gene (also known as MUL) cause Mulibrey (muscle-liver-brain-eye) nanism, a rare growth disorder of prenatal onset characterized by dysmorphic features, pericardial constriction, and hepatomegaly. TRIM37 belongs to the C-VIII subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox2, and a coiled coil region, as well as a MATH (meprin and TRAF-C homology) domain positioned C-terminal to the RBCC domain. Its MATH domain has been shown to interact with the TRAF (TNF-Receptor-Associated Factor) domain of six known TRAFs in vitro. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1005261091  93 DKCENHHEKLSVFCWTCKKCICHQCALWGGMHGGHTFKPL 132
Cdd:cd19779     1 DKCETHNEKLSVYCWTCKKCICHQCALWGGTHSGHTFKPL 40

meprin and TRAF homology;

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091  284 ENFSTLRqRADPVYSPPLQVSGLCWRLKVYPDGNgvvrgyYLSVFLELSAGLPETSKY--EYRVEMVHQSCNDptKNIIR 361
Cdd:smart00061   7 KNVSRLE-EGESYFSPSEEHFNIPWRLKIYRKNG------FLSLYLHCEKEECDSRKWsiEAEFTLKLVSQNG--KSLSK 77

                           90
                   ....*....|....*...
gi 1005261091  362 EFASDFEVGECWGYNRFF 379
Cdd:smart00061  78 KDKHVFEKPSGWGFSKFI 95

B-Box-type zinc finger;

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|...
gi 1005261091   91 EKDKCENHH-EKLSVFCWTCKKCICHQCALWggMHGGHTFKPL 132
Cdd:smart00336   2 RAPKCDSHGdEPAEFFCEECGALLCRTCDEA--EHRGHTVVLL 42

HC subclass of RING (RING-HC) finger and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers. Some have a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle, and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1005261091  13 FRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQRAQCPHC 54
Cdd:cd16449     1 LECPICLERLKDPVLLP-CGHVFCRECIRRLLESGSIKCPIC 41

Modified RING finger, C3HGC3-type, found in RING finger and WD repeat domain-containing protein 3 (RFWD3) and similar proteins; RFWD3, also known as RING finger protein 201 (RNF201) or FLJ10520, is an E3 ubiquitin-protein ligase that forms a complex with Mdm2 and p53 to synergistically ubiquitinate p53 and acts as a positive regulator of p53 stability in response to DNA damage. It is phosphorylated by checkpoint kinase ATM/ATR and the phosphorylation mutant fails to stimulate p53 ubiquitination. RFWD3 also functions as a novel replication protein A (RPA)-associated protein involved in DNA replication checkpoint control. RFWD3 contains an N-terminal SQ-rich region followed by a RING finger domain that exhibits robust E3 ubiquitin ligase activity toward p53, a coiled-coil domain and three WD40 repeats in the C-terminus, the latter two of which may be responsible for protein-protein interaction. The RING finger in this family is a modified C3HGC3-type RING finger, but not a canonical C3H2C3-type RING-H2 finger or C3HC4-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1005261091  15 CFICMEKLRDA---RLCP-HCSKLCCFSCIRRWLTEQRAQCPHCRAPLQLRELVN 65
Cdd:cd16450     5 CPICFEPWTSSgehRLVSlKCGHLFGYSCIEKWLKGKGKKCPQCNKKAKRSDIRP 59

Variant RING finger, HC subclass (C4C4-type), found in retinoblastoma-binding protein 6 (RBBP6) and similar proteins; RBBP6, also known as proliferation potential-related protein, protein P2P-R, retinoblastoma-binding Q protein 1 (RBQ-1), or p53-associated cellular protein of testis (PACT), is a nuclear E3 ubiquitin-protein ligase involved in multiple processes, such as the control of gene expression, mitosis, cell differentiation, and cell apoptosis. It plays a role in both promoting and inhibiting apoptosis in many human cancers, including esophageal, lung, hepatocellular, and colon cancers, familial myeloproliferative neoplasms, as well as in human immunodeficiency virus-associated nephropathy (HIVAN). It functions as an Rb- and p53-binding protein that plays an important role in chaperone-mediated ubiquitination and possibly in protein quality control. It acts as a scaffold protein to promote the assembly of the p53/TP53-MDM2 complex, resulting in an increase of MDM2-mediated ubiquitination and degradation of p53/TP53, and leading to both apoptosis and cell growth. It is also a double-stranded RNA-binding protein that plays a role in mRNA processing by regulating the human polyadenylation machinery and modulating expression of mRNAs with AU-rich 3' untranslated regions (UTRs). Moreover, RBBP6 ubiquitinates and destabilizes the transcriptional repressor ZBTB38 that negatively regulates transcription and levels of the MCM10 replication factor on chromatin. Furthermore, RBBP6 is involved in tunicamycin-induced apoptosis by mediating protein kinase (PKR) activation. RBBP6 contains an N-terminal ubiquitin-like domain and a C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger. RBBP6 interacts with chaperones Hsp70 and Hsp40 through its N-terminal ubiquitin-like domain. It promotes the ubiquitination of p53 by Hdm2 in an E4-like manner through its RING finger. It also interacts directly with the pro-proliferative transcription factor Y-box-binding protein-1 (YB-1) via its RING finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1005261091  13 FRCFICMEKLRDARLCPHCSKLCCFSCIRRWLTEQRAQCPHCRAPLQLREL 63
Cdd:cd16620     4 LKCPICKDLMKDAVLTPCCGNSFCDECIRTALLEEDFTCPTCKEPDVSPDA 54

Tumor Necrosis Factor Receptor (TNFR)-Associated Factor (TRAF) family, TRAF domain, C-terminal MATH subdomain; TRAF molecules serve as adapter proteins that link cell surface TNFRs and receptors of the interleukin-1/Toll-like family to downstream kinase signaling cascades which results in the activation of transcription factors and the regulation of cell survival, proliferation and stress responses in the immune and inflammatory systems. There are at least six mammalian and three Drosophila proteins containing TRAF domains. The mammalian TRAFs display varying expression profiles, indicating independent and cell type-specific regulation. They display distinct, as well as overlapping functions and interactions with receptors. Most TRAFs, except TRAF1, share N-terminal homology and contain a RING domain, multiple zinc finger domains, and a TRAF domain. TRAFs form homo- and heterotrimers through its TRAF domain. The TRAF domain can be divided into a more divergent N-terminal alpha helical region (TRAF-N), and a highly conserved C-terminal MATH subdomain (TRAF-C) with an eight-stranded beta-sandwich structure. TRAF-N mediates trimerization while TRAF-C interacts with receptors.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091 283 LENFSTLRQRAD-----PVYSPPLQVSG----LCwrLKVYPDGNGVVRGYYLSVFL-----ELSAGLPETSKYEYRVEMV 348
Cdd:cd00270     7 IKDYSRKLQEAVagsntVLYSPPFYTSRygykLC--LRLYLNGDGTGKGTHLSLFVhvmkgEYDALLEWPFRGKITLTLL 84

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1005261091 349 HQSCNDPTKNIIREFASD-----FEVGEC------WGYNRFFRLDLLANEGYLnpQNDTVILRFQV 403
Cdd:cd00270    85 DQSDDSKRKHITETFMPDpnssaFQRPPTgennigFGYPEFVPLEKLESRGYV--KDDTLFIKVEV 148

Ubiquitin-specific protease 21 (Ubp21p) family, MATH domain; composed of fungal proteins with similarity to Ubp21p of fission yeast. Ubp21p is a deubiquitinating enzyme that may be involved in the regulation of the protein kinase Prp4p, which controls the formation of active spliceosomes. Members of this family are similar to human HAUSP (Herpesvirus-associated ubiquitin-specific protease) in that they contain an N-terminal MATH domain and a C-terminal catalytic protease (C19 family) domain. HAUSP is also an ubiquitin-specific protease that specifically catalyzes the deubiquitylation of p53 and MDM2. The MATH domain of HAUSP contains the binding site for p53 and MDM2. Similarly, the MATH domain of members in this family may be involved in substrate binding.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1005261091 277 DSATFVLENFSTLRQRadpVYSPPLQVSGLCWRLKVYPDGNGVVRgyYLSVFLE------LSAGLPETSKYEYRVEMVHQ 350
Cdd:cd03775     1 QSFTWRIKNWSELEKK---VHSPKFKCGGFEWRILLFPQGNSQTG--GVSIYLEphpeeeEKAPLDEDWSVCAQFALVIS 75

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1005261091 351 SCNDPTKNIIREFASDFEVGEC-WGYNRFFRLDLLANEGYLNP----QNDTVILRFQVR 404
Cdd:cd03775    76 NPGDPSIQLSNVAHHRFNAEDKdWGFTRFIELRKLAHRTPDKPspflENGELNITVYVR 134

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1005261091  15 CFICMEKLRDARLCP--HCSklCCFSCIRRWLtEQRAQCPHCRAPLQ 59
Cdd:pfam13920   5 CVICLDRPRNVVLLPcgHLC--LCEECAERLL-RKKKKCPICRQPIE 48

B-box-type 2 zinc finger found in tripartite motif-containing proteins, TRIM16, TRIM29, TRIM47 and similar proteins; This family includes a group of tripartite motif-containing proteins, such as TRIM16, TRIM29 and TRIM47. TRIM16, also termed estrogen-responsive B box protein (EBBP), is a regulator that may play a role in the regulation of keratinocyte differentiation. It may also act as a tumor suppressor through affecting cell proliferation and migration or tumorigenicity in carcinogenesis. TRIM29, also termed ataxia telangiectasia group D-associated protein (ATDC), plays a crucial role in the regulation of macrophage activation in response to viral or bacterial infections within the respiratory tract. TRIM47, also known as gene overexpressed in astrocytoma protein (GOA) or RING finger protein 100 (RNF100), plays an important role in the process of dedifferentiation that is associated with astrocytoma tumorigenesis. TRIM16 and TRIM29 belong to an unclassified TRIM (tripartite motif) family of proteins that do not have RING fingers and thus lack the characteristic tripartite (RING (R), B-box, and coiled coil (CC)) RBCC motif. TRIM47 belongs to the C-IV subclass of TRIM family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1005261091  94 KCENHHEKLSVFCWTCKKCICHQCALwgGMHGGHTFKPLAE 134
Cdd:cd19769     2 VCPIHKKPLELFCRTDQMCICELCAK--EEHRGHDVVTVEE 40

RING finger, HC subclass, found in RING finger protein 219 (RNF219) and similar proteins; RNF219 may function as a modulator of late-onset Alzheimer's disease (LOAD) associated amyloid beta A4 precursor protein (APP) endocytosis and metabolism. It genetically interacts with apolipoprotein E epsilon4 allele (APOE4). Thus, a genetic variant of RNF219 was found to affect amyloid deposition in human brain and LOAD age-of-onset. Moreover, common genetic variants at the RNF219 locus had been associated with alternations in lipid metabolism, cognitive performance and central nervous system ventricle volume. RNF219 contains a C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1005261091  15 CFICMEKLRDARLCPHcSKLCCFSCIRRWLtEQRAQCPHCRAPL 58
Cdd:cd16562     4 CHICLGKVRQPVICSN-NHVFCSSCMDVWL-KNNNQCPACRVPI 45

B-box-type 2 zinc finger found in tripartite motif-containing protein 14 (TRIM14) and similar proteins; TRIM14 is a mitochondrial adaptor that facilitates innate immune signaling. It also plays a critical role in tumor development. TRIM14 belongs to an unclassified TRIM (tripartite motif) family of proteins that do not have RING fingers and thus lack the characteristic tripartite (RING (R), B-box, and coiled coil (CC)) RBCC motif. It contains a Bbox2 zinc finger as well as a C-terminal SPRY/B30.2 domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1005261091  93 DKCENHHE-KLSVFCWTCKKCICHQCALWGGmHGGHTFKPLAEIY 136
Cdd:cd19768     1 RCCPEHKDrPLELFCKTCKRCVCALCPILGQ-HRGHDVRLIDEEA 44

RING finger, HC subclass, found in topoisomerase I-binding arginine/serine-rich protein (Topors) and similar proteins; Topors, also known as topoisomerase I-binding RING finger protein, tumor suppressor p53- binding protein 3, or p53-binding protein 3 (p53BP3), is a ubiquitously expressed nuclear E3 ubiquitin-protein ligase that can ligate both ubiquitin and small ubiquitin-like modifier (SUMO) to substrate proteins in the nucleus. It contains an N-terminal C3HC4-type RING-HC finger which ligates ubiquitin to its target proteins including DNA topoisomerase I, p53, NKX3.1, H2AX, and the AAV-2 Rep78/68 proteins. As a RING-dependent E3 ubiquitin ligase, Topors works with the E2 enzymes UbcH5a, UbcH5c, and UbcH6, but not with UbcH7, CDC34, or UbcH2b. Topors acts as a tumor suppressor in various malignancies. It regulates p53 modification, suggesting it may be responsible for astrocyte elevated gene-1 (AEG-1, also known as metadherin, or LYRIC) ubiquitin modification. Plk1-mediated phosphorylation of Topors inhibits Topors-mediated sumoylation of p53, whereas p53 ubiquitination is enhanced, leading to p53 degradation. It also functions as a negative regulator of the prostate tumor suppressor NKX3.1. Moreover, Topors is associated with promyelocytic leukemia nuclear bodies, and may be involved in the cellular response to camptothecin. It also plays a key role in the turnover of H2AX protein, discriminating the type of DNA damaging stress. Furthermore, Topors is a cilia-centrosomal protein associated with autosomal dominant retinal degeneration. Mutations in TOPORS cause autosomal dominant retinitis pigmentosa (adRP).

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1005261091  15 CFICMEKLRD--ARLCPhCSKLCCFSCIRRWlTEQRAQCPHCRAP 57
Cdd:cd16574     4 CPICLDRFENekAFLDG-CFHAFCFTCILEW-SKVKNECPLCKQP 46

RING finger, HC subclass, found in RING finger protein 5 (RNF5) and similar proteins; RNF5, also known as protein G16 or Ram1, is an E3 ubiquitin-protein ligase anchored to the outer membrane of the endoplasmic reticulum (ER). It acts at early stages of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) biosynthesis and functions as a target for therapeutic modalities to antagonize mutant CFTR proteins in CF patients carrying the F508del allele. It also regulates the turnover of specific G protein-coupled receptors by ubiquitinating JNK-associated membrane protein (JAMP) and preventing proteasome recruitment. RNF5 limits basal levels of autophagy and influences susceptibility to bacterial infection through the regulation of ATG4B stability. It is also involved in the degradation of Pendrin, a transmembrane chloride/anion exchanger highly expressed in thyroid, kidney, and inner ear. RNF5 plays an important role in cell adhesion and migration. It can modulate cell migration by ubiquitinating paxillin. Furthermore, RNF5 interacts with virus-induced signaling adaptor (VISA) at mitochondria in a viral infection-dependent manner, and further targets VISA at K362 and K461 for K48-linked ubiquitination and degradation after viral infection. It also negatively regulates virus-triggered signaling by targeting MITA, also known as STING, for ubiquitination and degradation at the mitochondria. In addition, RNF5 determines breast cancer response to ER stress-inducing chemotherapies through the regulation of the L-glutamine carrier proteins SLC1A5 and SLC38A2 (SLC1A5/38A2). It also has been implicated in muscle organization and in recognition and processing of misfolded proteins. RNF5 contains a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1005261091  13 FRCFICMEKLRDA--RLCPHcskLCCFSCIRRWLTE--QRAQCPHCRA 56
Cdd:cd16743     1 FECNICLETARDAvvSLCGH---LFCWPCLHQWLETrpERQECPVCKA 45

RING finger, HC subclass, found in RING finger protein RNF5, RNF185 and similar proteins; RNF5 and RNF185 are E3 ubiquitin-protein ligases that are anchored to the outer membrane of the endoplasmic reticulum (ER). RNF5 acts at early stages of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) biosynthesis, and functions as a target for therapeutic modalities to antagonize mutant CFTR proteins in CF patients carrying the F508del allele. RNF185 controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical endoplasmic reticulum-associated degradation (ERAD) model substrates. Moreover, both RNF5 and RNF185 play important roles in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. Arabidopsis thaliana RING membrane-anchor proteins (AtRMAs) are also included in this family. They possess E3 ubiquitin-protein ligase activity and may play a role in the growth and development of Arabidopsis. All members of this family contain a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*
gi 1005261091  13 FRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTE--QRAQCPHCR 55
Cdd:cd16534     1 FECNICLDTASDPVVTM-CGHLFCWPCLYQWLETrpDRQTCPVCK 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 65 (TRIM65), B box and SPRY domain-containing protein (BSPRY) and similar proteins; The family includes TRIM65 and BSPRY. TRIM65 is an E3 ubiquitin-protein ligase that interacts with the innate immune receptor MDA5 enhancing its ability to stimulate interferon-beta signaling. It functions as a potential oncogenic protein that negatively regulates p53 through ubiquitination, providing insight into development of novel approaches targeting TRIM65 for non-small cell lung carcinoma (NSCLC) treatment, and also overcoming chemotherapy resistance. Moreover, TRIM65 negatively regulates microRNA-driven suppression of mRNA translation by targeting TNRC6 proteins for ubiquitination and degradation. BSPRY is a regulatory protein for maintaining calcium homeostasis. It may regulate epithelial calcium transport by inhibiting TRPV5 activity. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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                  ....*....|....*....|....*....|....*....|..
gi 1005261091  93 DKCENHHEKLSVFCWTCKKCICHQCALWGGMHgGHTFKPLAE 134
Cdd:cd19793     1 ELCPEHGRELELYCRTEKRCVCAQCASKGECR-GHRVTLLEE 41

N1R/p28-like protein; Provisional

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1005261091  15 CFICMEKLRDAR-------LCPHCSKLCCFSCIRRWlTEQRAQCPHCRAP 57
Cdd:PHA02929  177 CAICMEKVYDKEiknmyfgILSNCNHVFCIECIDIW-KKEKNTCPVCRTP 225

Modified RING finger, HC subclass (C3HC5-type), found in neuralized-like protein NEURL1A, NEURL1B, and similar proteins; This subfamily includes Drosophila neuralized (D-neu) protein, and its two mammalian homologs, NEURL1A and NEURL1B. D-neu is a regulator of the developmentally important Notch signaling pathway. NEURL1A, also known as NEURL1, NEU, neuralized 1, or RING finger protein 67 (RNF67), is a mammalian homolog of D-neu. It functions as an E3 ubiquitin-protein ligase that directly interacts with and monoubiquitinates cytoplasmic polyadenylation element-binding protein 3 (CPEB3), an RNA binding protein and a translational regulator of local protein synthesis, which facilitates hippocampal plasticity and hippocampal-dependent memory storage. It also acts as a potential tumor suppressor that causes apoptosis and downregulates Notch target genes in medulloblastoma. NEURL1B, also known as neuralized-2 (NEUR2) or neuralized-like protein 3, is another mammalian homolog of D-neu protein. It functions as an E3 ubiquitin-protein ligase that interacts with and ubiquitinates Delta. Thus, it plays a role in the endocytic pathways for Notch signaling by working cooperatively with another E3 ligase, Mind bomb-1 (Mib1), in Delta endocytosis to hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs)-positive vesicles. Members of this subfamily contain two neuralized homology regions (NHRs) responsible for Neural-ligand interactions and a modified C3HC5-type RING-HC finger required for ubiquitin ligase activity. The C3HC5-type RING-HC finger is distinguished from typical C3HC4-type RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1005261091  15 CFICMEKLRDARLCPhCSKLC-CFSCIRRwLTEQRAQCPHCRAPLQ 59
Cdd:cd16647     4 CVICYERPVDTVLYR-CGHMCmCYDCALQ-LKRRGGSCPICRAPIK 47

RING finger, HC subclass, found in Arabidopsis thaliana RING membrane-anchor proteins (AtRMAs) and similar proteins; AtRMAs, including AtRma1, AtRma2, and AtRma3, are endoplasmic reticulum (ER)-localized Arabidopsis homologs of human outer membrane of the ER-anchor E3 ubiquitin-protein ligase, RING finger protein 5 (RNF5). AtRMAs possess E3 ubiquitin ligase activity, and may play a role in the growth and development of Arabidopsis. The AtRMA1 and AtRMA3 genes are predominantly expressed in major tissues, such as cotyledons, leaves, shoot-root junction, roots, and anthers, while AtRMA2 expression is restricted to the root tips and leaf hydathodes. AtRma1 probably functions with the Ubc4/5 subfamily of E2. AtRma2 is likely involved in the cellular regulation of ABP1 expression levels through interacting with auxin binding protein 1 (ABP1). AtRMA proteins contain an N-terminal C3HC4-type RING-HC finger and a trans-membrane-anchoring domain in their extreme C-terminal region.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1005261091  13 FRCFICMEKLRDArLCPHCSKLCCFSCIRRWLTEQRAQ--CPHCRA 56
Cdd:cd16745     1 FECNICLDLAQDP-VVTLCGHLFCWPCLHKWLRRQSSQpeCPVCKA 45

DNA repair protein rad18; All proteins in this family for which functions are known are involved in nucleotide excision repair.This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

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                  ....*....|....*....|....*....|....*....|....*..
gi 1005261091  13 FRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQrAQCPHCRAPLQ 59
Cdd:TIGR00599  27 LRCHICKDFFDVPVLTS-CSHTFCSLCIRRCLSNQ-PKCPLCRAEDQ 71

B-box-type 2 zinc finger found in tripartite motif-containing protein 67 (TRIM67) and similar proteins; TRIM67, also termed TRIM9-like protein (TNL), is a protein selectively expressed in the cerebellum. It interacts with PRG-1, an important molecule in the control of hippocampal excitability dependent on presynaptic LPA2 receptor signaling, and 80K-H (also known as glucosidase II beta), a protein kinase C substrate. It negatively regulates Ras signaling in cell proliferation via degradation of 80K-H, leading to neural differentiation including neuritogenesis. TRIM67 belongs to the C-I subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, the fibronectin type III domain and the SPRY/B30.2 domain positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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                  ....*....|....*....|....*....|....*....|....
gi 1005261091  95 CENHH-EKLSVFCWTCKKCICHQCaLWGGMHGGHTFKPLAEIYE 137
Cdd:cd19827     3 CAEHElENYSMYCASCRTPVCYQC-LEEGKHAKHEVKALGAMWK 45

RING finger, HC subclass, found in RING finger protein 138 (RNF138) and similar proteins; RNF138, also known as Nemo-like kinase-associated RING finger protein (NARF) or NLK-associated RING finger protein, is an E3 ubiquitin-protein ligase that plays an important role in glioma cell proliferation, apoptosis, and cell cycle. It specifically cooperates with the E2 conjugating enzyme E2-25K (Hip-2/UbcH1), regulates the ubiquitylation and degradation of T cell factor/lymphoid enhancer factor (TCF/LEF), and further suppresses Wnt-beta-catenin signaling. RNF138, together with three closely related proteins: RNF114, RNF125 and RNF166, forms a novel family of ubiquitin ligases with a C3HC4-type RING-HC finger, a C2HC-, and two C2H2-type zinc fingers, as well as a ubiquitin interacting motif (UIM).

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                  ....*....|....*....|....*....|....*....|....*....|..
gi 1005261091  11 EVFRCFICMEKLRDARLCPHCSKLCCFSCIRRWLTEQRAQCPHCRAPLQLRE 62
Cdd:cd16544     1 AELTCPVCQEVLKDPVELPPCRHIFCKACILLALRSSGARCPLCRGPVGKTE 52

B-box-type 2 zinc finger found in B box and SPRY domain-containing protein (BSPRY) and similar proteins; BSPRY is a regulatory protein for maintaining calcium homeostasis. It may regulate epithelial calcium transport by inhibiting TRPV5 activity. BSPRY is composed of a B-box, an alpha-helical coiled coil and a SPRY domain. The B-box motif shows high sequence similarity with B-Box-type zinc finger 2 found in tripartite motif-containing proteins (TRIMs). The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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                  ....*....|....*....|....*....|....*....|..
gi 1005261091  93 DKCENHHEKLSVFCWTCKKCICHQCALWGGMHgGHTFKPLAE 134
Cdd:cd19834     1 DLCPDHELELDWFCSTERRLVCAQCASLGTCR-GHRVTPLEE 41

RING finger, H2 subclass, found in Arabidopsis thaliana RING-H2 finger A1a (RHA1A), A1b (RHA1B) and similar proteins; This subfamily includes Arabidopsis thaliana RHA1A, RHA1B and XERICO. RHA1A is a probable E3 ubiquitin-protein ligase that may possess E3 ubiquitin ligase activity in vitro. RHA1B possesses E3 ubiquitin-protein ligase activity when associated with the E2 enzyme UBC8 in vitro. XERICO functions on abscisic acid homeostasis at post-translational level, probably through ubiquitin/proteasome-dependent substrate-specific degradation. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1005261091  14 RCFICMEKLRDA---RLCPHCSKLCCFSCIRRWLTEQRAQCPHCRAPL 58
Cdd:cd23121     3 CCAICLSDFNSDeklRQLPKCGHIFHHHCLDRWIRYNKITCPLCRADL 50

RING finger, HC subclass, found in midline-2 (MID2) and similar proteins; MID2, also known as midin-2, midline defect 2, RING finger protein 60 (RNF60), or tripartite motif-containing protein 1 (TRIM1), is a probable E3 ubiquitin-protein ligase and is highly related to MID1 that associates with cytoplasmic microtubules along their length and throughout the cell cycle. Like MID1, MID2 associates with the microtubule network and may at least partially compensate for the loss of MID1. Both MID1 and MID2 interacts with Alpha 4, which is a regulatory subunit of PP2-type phosphatases, such as PP2A, and an integral component of the rapamycin-sensitive signaling pathway. MID2 can also substitute for MID1 to control exocytosis of lytic granules in cytotoxic T cells. Loss-of-function mutations in MID2 lead to the human X-linked intellectual disability (XLID). MID2 belongs to the C-I subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxy-terminal subgroup one signature) box, a fibronectin type III (FN3) domain, and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. MID2 hetero-dimerizes in vitro with its paralog MID1.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1005261091   6 VESIAEVFRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQRA-----------QCPHCRAPLQL 60
Cdd:cd16754     1 METLESELTCPICLELFEDPLLLP-CAHSLCFSCAHRILTSGCAsgesieppsafQCPTCRYVISL 65

RING finger, HC subclass, found in RING finger protein 169 (RNF169) and similar proteins; RNF169 is an uncharacterized E3 ubiquitin-protein ligase paralogous to RNF168. It functions as a negative regulator of the DNA damage signaling cascade. RNF169 recognizes polyubiquitin structures but does not itself contribute to double-strand break (DSB)-induced chromatin ubiquitylation. It contributes to regulation of the DSB repair pathway utilization via functionally competing with recruiting repair factors, 53BP1 and RAP80-BRCA1, for association with RNF168-modified chromatin independent of its catalytic activity, limiting the magnitude of the RNF8/RNF168-dependent signaling response to DSBs. RNF169 contains an N-terminal C3HC4-type RING-HC finger and a C-terminal MIU (motif interacting with ubiquitin) domain.

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gi 1005261091  13 FRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQRAQ--CPHCRAPL 58
Cdd:cd16551     2 LTCAGCLEVPVEPATLP-CGHTLCRGCANRALDAAEAGptCPRCRAPL 48

RING finger, HC subclass, found in the makorin (MKRN) proteins; The MKRN protein subfamily includes ribonucleoproteins that are characterized by a variety of zinc-finger motifs, including typical arrays of one to four C3H1-type zinc fingers and a C3HC4-type RING-HC finger. Another motif rich in Cys and His residues (CH), with so far unknown function, is also generally present in MKRN proteins. MKRN proteins may have E3 ubiquitin ligase activity.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1005261091  15 CFICMEK-LRDAR---LCPHCSKLCCFSCIRRW------LTEQRAQCPHCR 55
Cdd:cd16521     3 CGICMEVvLEKERrfgILSNCNHVFCLECIREWrsskdfENSIVRSCPICR 53

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl and similar proteins; Cbl, also known as Casitas B-lineage lymphoma proto-oncogene, proto-oncogene c-Cbl, RING finger protein 55 (RNF55), or signal transduction protein Cbl, is a multi-domain protein that acts as a key negative regulator of various receptor and non-receptor tyrosine kinase signaling. It contains a tyrosine kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain), a proline-rich domain, a C3HC4-type RING-HC finger, and an ubiquitin-associated (UBA) domain. TKB is responsible for the interactions with many tyrosine kinases, such as the colony-stimulating factor-1 (CSF-1) receptor, Syk/ZAP-70, and Src-family of protein tyrosine kinases. The proline-rich domain can recruit proteins with a SH3 domain. Moreover, Cbl functions as an E3 ubiquitin ligase that can bind ubiquitin-conjugating enzymes (E2s) through the RING-HC finger.

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gi 1005261091  15 CFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQRAQCPHCRAPLQLRE 62
Cdd:cd16708    24 CKICAENDKDVKIEP-CGHLMCTSCLTSWQESEGQGCPFCRCEIKGTE 70

RING finger, HC subclass, found in tripartite motif-containing proteins, TRIM7, TRIM11 and TRIM27, and similar proteins; TRIM7, TRIM11 and TRIM27, closely related tripartite motif-containing proteins, belong to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) by mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. TRIM11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM27, also known as RING finger protein 76 (RNF76), RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. In addition, it inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. TRIM27 promotes a non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. TRIM27 also forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is a component of an estrogen receptor 1 (ESR1) regulatory complex that is involved in estrogen receptor-mediated transcription in MCF-7 cells.

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gi 1005261091  15 CFICMEKLRDarlcP---HCSKLCCFSCIRR-W-LTEQRAQCPHCRAPLQLRELVNCR 67
Cdd:cd16594     8 CPICLDYFTD----PvtlDCGHSFCRACIARcWeEPETSASCPQCRETCPQRNLRPNR 61

RING finger, HC subclass, found in Saccharomyces cerevisiae radiation sensitivity protein 18 (RAD18) and similar proteins; RAD18, also called RING-type E3 ubiquitin transferase RAD18, acts as a postreplication repair E3 ubiquitin-protein ligase that associates with the E2 ubiquitin conjugating enzyme UBC2/RAD6 to form the UBC2-RAD18 ubiquitin ligase complex involved in postreplicative repair (PRR) of damaged DNA. The UBC2-RAD18 complex cooperates with RAD5 and the UBC13-MMS2 dimer to attach mono-ubiquitin chains on 'Lys-164' of POL30, which is necessary for PRR. The UBC2-RAD18 complex is also involved in prevention of spontaneous mutations caused by 7,8-dihydro-8-oxoguanine. RAD18 is an E3 RING-finger protein belonging to the UBC2/RAD6 epistasis group. It contains a typical C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1005261091  13 FRCFICMEKLRDARLCPhCSKLCCFSCIRRWLTEQrAQCPHCRAPLQLREL 63
Cdd:cd23148     4 LRCHICKDLLKAPMRTP-CNHTFCSFCIRTHLNND-ARCPLCKAEVTESGL 52