RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2217355636 428 DSYICAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSSTPCPLCRTIISRVFFQTEL 486
Cdd:cd16554     1 ESLTCPVCLDLYYDPYMCYPCGHIFCEPCLRQLAKSSPKNTPCPLCRTTIRRVFFQEEL 59

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2217355636 428 DSYICAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSSTPCPLCRTIISRVFFQTEL 486
Cdd:cd16554     1 ESLTCPVCLDLYYDPYMCYPCGHIFCEPCLRQLAKSSPKNTPCPLCRTTIRRVFFQEEL 59

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|..
gi 2217355636  432 CAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSStpCPLC 473
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWLESGNNT--CPIC 40

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 2217355636 432 CAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSstpCPLCR 474
Cdd:TIGR00599  29 CHICKDFFDVP-VLTSCSHTFCSLCIRRCLSNQPK---CPLCR 67

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2217355636 428 DSYICAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSSTPCPLCRTIISRVFFQTEL 486
Cdd:cd16554     1 ESLTCPVCLDLYYDPYMCYPCGHIFCEPCLRQLAKSSPKNTPCPLCRTTIRRVFFQEEL 59

RING finger, HC subclass, found in Caenorhabditis elegans RING finger protein NHL-1 and similar proteins; NHL-1 functions as an E3 ubiquitin-protein ligase in the presence of both UBC-13 and UBC-1 within the ubiquitin pathway of Caenorhabditis elegans. It acts in chemosensory neurons to promote stress resistance in distal tissues by the transcription factor DAF-16 activation but is dispensable for the activation of heat shock factor 1 (HSF-1). NHL-1 belongs to the TRIM (tripartite motif)-NHL 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 domain, as well as an NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2217355636 432 CAVCLDVYFNPYMcYPCHHIFC-EPCLRTLAKDNPSSTPCPLCRTI 476
Cdd:cd16524     8 CPICLDRYRRPKL-LPCQHTFClSPCLEGLVDYVTRKLKCPECRAE 52

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 2217355636 430 YICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSStpCPLC 473
Cdd:cd16449     1 LECPICLERLKDP-VLLPCGHVFCRECIRRLLESGSIK--CPIC 41

RING-type zinc-finger; This zinc-finger is a typical RING-type of plant ubiquitin ligases.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 2217355636 432 CAVCLDVYFNPYMcyPCHHIFCEPCLRTLAKDNPSSTPCP 471
Cdd:pfam13445   1 CPICLELFTDPVL--PCGHTFCRECLEEMSQKKGGKFKCP 38

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 2217355636 432 CAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSstpCPLC 473
Cdd:pfam13923   2 CPICMDMLKDPSTTTPCGHVFCQDCILRALRAGNE---CPLC 40

RING finger, HC subclass, found in tripartite motif-containing protein 77 (TRIM77) and similar proteins; TRIM77 belongs 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 two consecutive zinc-binding domains, a C3HC4-type RING-HC finger and Bbox2, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 2217355636 428 DSYICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSSTPCPLCRTIISR 479
Cdd:cd16543     2 DQLTCSICLDLLKDP-VTIPCGHSFCMNCITLLWDRKQGVPSCPQCRESFPP 52

RING finger, HC subclass, found in RING finger protein 125 (RNF125); RNF125, also known as T-cell RING activation protein 1 (TRAC-1), is an E3 ubiquitin-protein ligase that is predominantly expressed in lymphoid cells, and functions as a positive regulator of T cell activation. It also down-modulates HIV replication and inhibits pathogen-induced cytokine production. It negatively regulates type I interferon signaling, which conjugates Lys(48)-linked ubiquitination to retinoic acid-inducible gene-I (RIG-I) and subsequently leads to the proteasome-dependent degradation of RIG-I. Further, RNF125 conjugates ubiquitin to melanoma differentiation-associated gene 5 (MDA5), a family protein of RIG-I. It thus acts as a negative regulator of RIG-I signaling, and is a direct target of miR-15b in the context of Japanese encephalitis virus (JEV) infection. Moreover, RNF125 binds to and ubiquitinates JAK1, prompting its degradation and inhibition of receptor tyrosine kinase (RTK) expression. It also negatively regulates p53 function through physical interaction and ubiquitin-mediated proteasome degradation. Mutations in RNF125 may lead to overgrowth syndromes (OGS). RNF125, together with three closely related proteins: RNF114, RNF138 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). The UIM of RNF125 binds K48-linked poly-ubiquitin chains and is, together with the RING domain, required for auto-ubiquitination.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2217355636 429 SYICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSStpCPLCRTIISR 479
Cdd:cd16542     1 NFDCAVCLEVLHQP-VRTRCGHVFCRPCIATSLRNNTWT--CPYCRAYLSS 48

RING finger, HC subclass, found in tripartite motif-containing protein 3 (TRIM3); TRIM3, also known as brain-expressed RING finger protein (BERP), RING finger protein 97 (RNF97), or RING finger protein 22 (RNF22), is an E3 ubiquitin-protein ligase involved in the pathogenesis of various cancers. It functions as a tumor suppressor that regulates asymmetric cell division in glioblastoma. It binds to the cdk inhibitor p21(WAF1/CIP1) and regulates its availability that promotes cyclin D1-cdk4 nuclear accumulation. Moreover, TRIM3 plays an important role in the central nervous system (CNS). It is encoded by the gene BERP (brain-expressed RING finger protein), a unique p53-regulated gene that modulates seizure susceptibility and GABAAR cell surface expression. Furthermore, TRIM3 mediates activity-dependent turnover of postsynaptic density (PSD) scaffold proteins GKAP/SAPAP1 and is a negative regulator of dendritic spine morphology. In addition, TRIM3 may be involved in vesicular trafficking via its association with the cytoskeleton-associated-recycling or transport (CART) complex that is necessary for efficient transferrin receptor recycling, but not for epidermal growth factor receptor (EGFR) degradation. It also regulates the motility of the kinesin superfamily protein KIF21B. TRIM3 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is 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 domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 2217355636 426 EKDSYICAVCLDVYFNPYMcYPCHHIFCEPCLRTLAKDNPSSTPCPLCR 474
Cdd:cd16768     1 DKQFLVCSICLDRYHNPKV-LPCLHTFCERCLQNYIPPQSLTLSCPVCR 48

RING finger, HC subclass, found in tripartite motif-containing protein TRIM2, TRIM3, and similar proteins; TRIM2, also known as RING finger protein 86 (RNF86), is an E3 ubiquitin-protein ligase that ubiquitinates the neurofilament light chain, a component of the intermediate filament in axons. Loss of function of TRIM2 results in early-onset axonal neuropathy. TRIM3, also known as brain-expressed RING finger protein (BERP), RING finger protein 97 (RNF97), or RING finger protein 22 (RNF22), is an E3 ubiquitin-protein ligase involved in the pathogenesis of various cancers. It also plays an important role in the central nervous system (CNS). In addition, TRIM3 may be involved in vesicular trafficking via its association with the cytoskeleton-associated-recycling or transport (CART) complex that is necessary for efficient transferrin receptor recycling, but not for epidermal growth factor receptor (EGFR) degradation. Both TRIM2 and TRIM3 belong to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is 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 domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2217355636 431 ICAVCLDVYFNPYMcYPCHHIFCEPCLRTLAKDNPSSTPCPLCR 474
Cdd:cd16586     3 SCGICLERYKNPKV-LPCLHTFCERCLQNYIPAESLSLSCPVCR 45

RING finger, HC subclass, found in RING finger protein 114 (RNF114) and similar proteins; RNF114, also known as zinc finger protein 228 (ZNF228) or zinc finger protein 313 (ZNF313), is a p21(WAF1)-targeting ubiquitin E3 ligase that interacts with X-linked inhibitor of apoptosis (XIAP)-associated factor 1 (XAF1) and may play a role in p53-mediated cell-fate decisions. It is involved in the immune response to double-stranded RNA in disease pathogenesis. Moreover, RNF114 interacts with A20 and modulates its ubiquitylation. It negatively regulates nuclear factor-kappaB (NF-kappaB)-dependent transcription and positively regulates T-cell activation. RNF114 may play a putative role in the regulation of immune responses, since it corresponds to a novel psoriasis susceptibility gene, ZNF313. RNF114, together with three closely related proteins: RNF125, RNF138 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).

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2217355636 430 YICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKdnPSSTPCPLCRT 475
Cdd:cd16540     2 FTCPVCLEIFETP-VRVPCGHVFCNACLQECLK--PKKPVCAVCRS 44

RING finger, HC subclass, found in tripartite motif-containing protein TRIM65 and similar proteins; 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 the 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. TRIM65 belongs 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, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2217355636 432 CAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSST-PCPLCR 474
Cdd:cd16609     6 CSICLGLYQDP-VTLPCQHSFCRACIEDHWRQKDEGSfSCPECR 48

RING finger, HC subclass, found in tripartite motif-containing protein 2 (TRIM2); TRIM2, also known as RING finger protein 86 (RNF86), is an E3 ubiquitin-protein ligase that ubiquitinates the neurofilament light chain, a component of the intermediate filament in axons. Loss of function of TRIM2 results in early-onset axonal neuropathy. TRIM2 also plays a role in mediating the p42/p44 MAPK-dependent ubiquitination of the cell death-promoting protein Bcl-2-interacting mediator of cell death (Bim) in rapid ischemic tolerance. TRIM2 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is 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 domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 2217355636 426 EKDSYICAVCLDVYFNPYMcYPCHHIFCEPCLRTLAKDNPSSTPCPLCR 474
Cdd:cd16767     3 DKQFLICSICLDRYKNPKV-LPCLHTFCERCLQNYIPAHSLTLSCPVCR 50

RING finger, HC subclass, found in checkpoint with forkhead and RING finger domains protein (CHFR); CHFR, also known as RING finger protein 196 (RNF196), is a checkpoint protein that delays entry into mitosis in response to stress. It functions as an E3 ubiquitin ligase that ubiquitinates and degrades its target proteins, such as Aurora-A, Plk1, Kif22, and PARP-1, which are critical for proper mitotic transitions. It also plays an important role in cell cycle progression and tumor suppression, and is negatively regulated by SUMOylation-mediated proteasomal ubiquitylation. Moreover, CHFR is involved in the early stage of the DNA damage response, which mediates the crosstalk between ubiquitination and poly-ADP-ribosylation. CHFR contains a fork head associated (FHA) domain and a C3HC4-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2217355636 428 DSYICAVCLDVYFNPYMCYPCHHIFCEPCLRTLAkdNPSSTPCPLCRTIISRV 480
Cdd:cd16503     1 ENLTCSICQDLLHDCVSLQPCMHNFCAACYSDWM--ERSNTECPTCRATVQRV 51

RING finger, HC subclass, found in RING finger protein 166 (RNF166) and similar proteins; RNF166 is encoded by the gene RNF166 targeted by thyroid hormone receptor alpha1 (TRalpha1), which is important in brain development. It plays an important role in RNA virus-induced interferon-beta production by enhancing the ubiquitination of TRAF3 and TRAF6. RNF166, together with three closely related proteins: RNF114, RNF125 and RNF138, 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).

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 2217355636 430 YICAVCLDVYFNPYMCYPCHHIFC----EPCLRTlakdnpSSTPCPLCR 474
Cdd:cd16549     2 FSCPICLEVYHKPVVITSCGHTFCgeclQPCLQV------ASPLCPLCR 44

RING-finger-containing E3 ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 2217355636 429 SYICAVCLDVYFNPyMCYPCHHIFCEPCL---RTLAKdnpsSTPCPLCR 474
Cdd:COG5574   215 DYKCFLCLEEPEVP-SCTPCGHLFCLSCLlisWTKKK----YEFCPLCR 258

second RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the second RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2217355636 432 CAVCLDVYFNPyMCYPCHHIFCEPCL-RTLAKdnpsSTPCPLCRT 475
Cdd:cd16514     4 CSLCLRLLYEP-VTTPCGHTFCRACLeRCLDH----SPKCPLCRT 43

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2217355636 430 YICAVCLDVYFNPYMCyPCHHIFCEPCLRTLAKDNPSSTPCPLCR 474
Cdd:cd16534     1 FECNICLDTASDPVVT-MCGHLFCWPCLYQWLETRPDRQTCPVCK 44

RING finger, HC subclass, found in Arabidopsis thaliana protein BENZOIC ACID HYPERSENSITIVE 1 (BAH1) and similar proteins; This subfamily includes Arabidopsis thaliana BAH1 and BAH1-like. BAH1, also known as protein NITROGEN LIMITATION ADAPTATION (NLA), or RING-type E3 ubiquitin transferase BAH1, acts as an E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. It plays a role in salicylic acid-mediated negative feedback regulation of salicylic acid (SA) accumulation. It may be involved in the overall regulation of SA, benzoic acid and phenylpropanoid biosynthesis. It controls the adaptability to nitrogen limitation by channeling the phenylpropanoid metabolic flux to the induced anthocyanin synthesis. BAH1-like, also known as RING finger protein 178, or RING-type E3 ubiquitin transferase BAH1-like, is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2217355636 432 CAVCLDVYFNPYmCYPCHHIFCEPCLRTLA--------KDNPSSTPCPLCRTI 476
Cdd:cd23127    11 CSICLDTVFDPV-ALGCGHLFCNSCACSAAsvlifqglKAAPPEAKCPLCRQD 62

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV 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 C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2217355636 427 KDSYICAVCLDVYFNPYMcYPCHHIFCEPCLRTLAKDNPSSTP-CPLCRT 475
Cdd:cd16597     3 EEELTCSICLELFKDPVT-LPCGHNFCGVCIEKTWDSQHGSEYsCPQCRA 51

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2217355636 431 ICAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSstpCPLCRTI 476
Cdd:cd16506     2 TCPICLDEIQNKKTLEKCKHSFCEDCIDRALQVKPV---CPVCGVV 44

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 2217355636 432 CAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSstpCPLCR 474
Cdd:TIGR00599  29 CHICKDFFDVP-VLTSCSHTFCSLCIRRCLSNQPK---CPLCR 67

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
                  ....*....|....*....|....*....|....*....|....*...
gi 2217355636 428 DSYICAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNPSStpCPLCRT 475
Cdd:cd16620     2 DELKCPICKDLMKDAVLTPCCGNSFCDECIRTALLEEDFT--CPTCKE 47

RING finger, HC subclass, found in Candida albicans transcriptional regulator of yeast form adherence 3 (TRY3) and similar proteins; TRY3 acts as a transcription factor required for yeast cell adherence to silicone substrate. It contains a typical C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2217355636 428 DSYICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSStpCPLCR 474
Cdd:cd23137     1 DDYACPICMNVAWKP-VRLECSHVFCLRCLVKAQKQKKDN--CPLCR 44

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 2(RNFT2); RNFT2, also known as transmembrane protein 118 (TMEM118), is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2217355636 431 ICAVCLDVYFNPYMCYpCHHIFCEPCLrTLAKDNPSStpCPLCRTII 477
Cdd:cd16742    15 ICAICQAEFREPLILI-CQHVFCEECL-CLWFDRERT--CPLCRSVV 57

RING finger, HC subclass, found in RING finger protein 10 (RNF10) and similar proteins; RNF10 is an E3 ubiquitin-protein ligase that interacts with mesenchyme Homeobox 2 (MEOX2) transcription factor, a regulator of the proliferation, differentiation and migration of vascular smooth muscle cells and cardiomyocytes; it enhances Meox2 activation of the p21 promoter. It also regulates the expression of myelin-associated glycoprotein (MAG) genes and is required for myelin production in Schwann cells of the peripheral nervous system. Moreover, RNF10 regulates retinoic acid-induced neuronal differentiation and the cell cycle exit of P19 embryonic carcinoma cells. RNF10 contains a C3HC4-type RING-HC finger and three putative nuclear localization signals.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 2217355636 432 CAVCLDVYFNPYMCyPCHHIFCEPC-LRTLAKDNPSSTPCPLCRTIIS 478
Cdd:cd16536     3 CPICLEPPVAPRIT-RCGHIFCWPCiLRYLSLSEKKWRKCPICFESIH 49

RING finger, HC subclass, found in RING finger protein 146 (RNF146) and similar proteins; RNF146, also known as dactylidin, or iduna, is a cytoplasmic E3 ubiquitin-protein ligase that is responsible for PARylation-dependent ubiquitination (PARdU). It displays neuroprotective property due to its inhibition of Parthanatos, a PAR dependent cell death, via binding with Poly(ADP-ribose) (PAR). It also modulates PAR polymerase-1 (PARP-1)-mediated oxidative cell injury in cardiac myocytes. Moreover, RNF146 mediates tankyrase-dependent degradation of axin, thereby positively regulating Wnt signaling. It also facilitates DNA repair and protects against cell death induced by DNA damaging agents or gamma-irradiation by translocating to the nucleus after cellular injury and promoting the ubiquitination and degradation of various nuclear proteins involved in DNA damage repair. Furthermore, RNF146 is implicated in neurodegenerative disease and cancer development. It regulates the development and progression of non-small cell lung cancer (NSCLC) by enhancing cell growth, invasion, and survival. RNF146 contains an N-terminal C3HC4-type RING-HC finger followed by a WWE domain with a poly(ADP-ribose) (PAR) binding motif at the tail.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2217355636 432 CAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKdnpSSTPCPLCRTIISRVF 481
Cdd:cd16546     3 CPICLQTCIHP-VKLPCGHIFCYLCVKGVAW---QSKRCALCRQEIPEDF 48

RING finger, HC subclass, found in tripartite motif-containing protein 72 (TRIM72) and similar proteins; TRIM72, also known as Mitsugumin-53 (MG53), is a muscle-specific protein that plays a central role in cell membrane repair by nucleating the assembly of the repair machinery at muscle injury sites. It is required in repair of alveolar epithelial cells under plasma membrane stress failure. It interacts with dysferlin to regulate sarcolemmal repair. Upregulation of TRIM72 develops obesity, systemic insulin resistance, dyslipidemia, and hyperglycemia, as well as induces diabetic cardiomyopathy through transcriptional activation of the peroxisome proliferation-activated receptor alpha (PPAR-alpha) signaling pathway. Compensation for the absence of AKT signaling by ERK signaling during TRIM72 overexpression leads to pathological hypertrophy. Moreover, TRIM72 functions as a novel negative feedback regulator of myogenesis by targeting insulin receptor substrate-1 (IRS-1). It is transcriptionally activated by the synergism of myogenin (MyoD) and myocyte enhancer factor 2 (MEF2). TRIM72 belongs 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, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2217355636 432 CAVCLDVYFNPYMCyPCHHIFCEPCLRTLAKD-NPSSTPCPLCRTI 476
Cdd:cd16612     7 CPLCLKLFQSPVTT-ECGHTFCQDCLSRVPKEeDGGSTSCPTCQAP 51

RING finger, HC subclass, 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 (LSCC), gastric cancer (GC), esophageal squamous cell carcinoma (ESCC), colorectal cancer, prostate cancer, and breast cancer. UHRF1 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 transcription 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) by interacting with the 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 C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2217355636 430 YICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSStpCPLCRT 475
Cdd:cd16613     1 FTCICCQELVYKP-ITTPCKHNICKSCLQRSFKAEVYT--CPACRH 43

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 1 (RNFT1); RNFT1, also known as protein PTD016, is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2217355636 431 ICAVCLDVYFNPYMCYpCHHIFCEPCLRTLAkdNPSSTpCPLCRTII 477
Cdd:cd16741    16 ICAICQAEFRKPILLI-CQHVFCEECISLWF--NREKT-CPLCRTVI 58

RING finger, HC subclass, found in tripartite motif-containing protein 69 (TRIM69) and similar proteins; TRIM69, also known as RFP-like domain-containing protein trimless or RING finger protein 36 (RNF36), is a testis E3 ubiquitin-protein ligase that plays a specific role in apoptosis and may also play an important role in germ cell homeostasis during spermatogenesis. TRIM69 belongs 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, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2217355636 431 ICAVCLDVYFNPYMcYPCHHIFCEPCLRTLAKDNPSSTPCPLCR 474
Cdd:cd16611     6 HCPLCLDFFRDPVM-LSCGHNFCQSCITGFWELQAEDTTCPECR 48

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.

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                  ....*....|....*....|....*....|....*....|....*.
gi 2217355636 432 CAVCLDVYFNPYMCyPCHHIFCEPCLRTLAKDNpssTPCPLCRTII 477
Cdd:cd16562     4 CHICLGKVRQPVIC-SNNHVFCSSCMDVWLKNN---NQCPACRVPI 45

RING finger, HC subclass, found in promyelocytic leukemia protein (PML) and similar proteins; Protein PML, also known as RING finger protein 71 (RNF71) or tripartite motif-containing protein 19 (TRIM19), is predominantly a nuclear protein with a broad intrinsic antiviral activity. It is the eponymous component of PML nuclear bodies (PML NBs) and has been implicated in a wide variety of cell processes, including DNA damage signaling, apoptosis, and transcription. PML interferes with the replication of many unrelated viruses, including human immunodeficiency virus 1 (HIV-1), human foamy virus (HFV), poliovirus, influenza virus, rabies virus, EMCV, adeno-associated virus (AAV), and vesicular stomatitis virus (VSV). It also selectively interacts with misfolded proteins through distinct substrate recognition sites and conjugates these proteins with the small ubiquitin-like modifiers (SUMOs) through its SUMO ligase activity. PML belongs to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as an uncharacterized region positioned C-terminal to the RBCC domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2217355636 426 EKDSYICAVCLDVYFNPYMcYPCHHIFCEPCLRTLAKDNPSSTP--CPLCR 474
Cdd:cd16579     1 EFKFLRCPGCKAEYKCPKL-LPCLHTVCSGCLEALAEQASETTEfqCPICK 50

RING finger, HC subclass, found in tripartite motif-containing protein TRIM21 and similar proteins; TRIM21, also known as 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A, Ro(SS-A), RING finger protein 81 (RNF81), or Sjoegren syndrome type A antigen (SS-A), is a ubiquitously expressed E3 ubiquitin-protein ligase and a high affinity antibody receptor uniquely expressed in the cytosol of mammalian cells. As a cytosolic Fc receptor, TRIM21 binds the Fc of virus-associated antibodies and targets the complex in the cytosol for proteasomal degradation in a process known as antibody-dependent intracellular neutralization (ADIN), and provides an intracellular immune response to protect host defense against pathogen infection. It shows remarkably broad isotype specificity as it does not only bind IgG, but also IgM and IgA. Moreover, TRIM21 promotes the cytosolic DNA sensor cGAS and the cytosolic RNA sensor RIG-I sensing of viral genomes during infection by antibody-opsonized virus. It stimulates inflammatory signaling and activates innate transcription factors, such as nuclear factor-kappaB (NF-kappaB). TRIM21 also plays an essential role in p62-regulated redox homeostasis, suggesting it may be a viable target for treating pathological conditions resulting from oxidative damage. Furthermore, TRIM21 may have implications for various autoimmune diseases associated with uncontrolled antiviral signaling through the regulation of Nmi-IFI35 complex-mediated inhibition of innate antiviral response. TRIM21 belongs 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, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2217355636 432 CAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSStpCPLCR 474
Cdd:cd16596    12 CPICLDPFVEP-VSIECGHSFCQECISQVGKGGGSV--CPVCR 51

Modified RING finger, HC subclass (C3HC3D-type), found in ligand of Numb protein LNX1, LNX2, and similar proteins; The ligand of Numb protein X (LNX) family, also known as PDZ and RING (PDZRN) family, includes LNX1-5, which can interact with Numb, a key regulator of neurogenesis and neuronal differentiation. LNX5 (also known as PDZK4 or PDZRN4L) shows high sequence homology to LNX3 and LNX4, but it lacks the RING domain. LNX1-4 proteins function as E3 ubiquitin ligases and have a unique domain architecture consisting of an N-terminal RING-HC finger for E3 ubiquitin ligase activity and either two or four PDZ domains necessary for substrate-binding. LNX1/LNX2-like proteins contain a modified C3HC3D-type RING-HC finger and four PDZ domains. This model corresponds to the RING finger.

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                  ....*....|....*....|....*....|....*....|....*
gi 2217355636 430 YICAVCLDVYFNPyMCYPCHHIFCEPCLRTLAKDNPSstpCPLCR 474
Cdd:cd16637     2 LTCHICLQPLVEP-LDTPCGHTFCYKCLTNYLKIQQC---CPLDR 42

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

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                  ....*....|....*....|....*....|....*....|....
gi 2217355636 432 CAVCLDVYFNPYMCYPCHHIFCEPCLRTLAKDNpSSTPCPLCRT 475
Cdd:cd16749     3 CPVCFEKLDVTAKVLPCQHTFCKPCLQRIFKAR-KELRCPECRT 45

RING finger, HC subclass, found in RNA polymerase II transcription factor B subunit 3 (TFB3) from fungi; TFB3, also known as RNA polymerase II transcription factor B 38 kDa subunit, RNA polymerase II transcription factor B p38 subunit, or Rig2, is a component of the general transcription and DNA repair factor IIH (TFIIH or factor B), which is essential for both basal and activated transcription and is involved in nucleotide excision repair (NER) of damaged DNA. TFIIH has CTD kinase and DNA-dependent ATPase activities, and is essential for polymerase II transcription in vitro. TFB3 is a homolog of MAT1 of higher eukaryotes which forms a ternary complex with MO15 (cdk7) and cyclin H. It physically interacts with Ubc4 and the Nedd8-conjugating enzyme Ubc12 as well as the Hrt1/Rtt101 complex. It targets the yeast Cul4-type cullin Rtt101 for its neddylation and ubiquitylation, and regulates neddylation and activity of cullin-3, but not Cdc53. TFB3 contains an N-terminal C3HC4-type RING-HC finger and a C-terminal MAT1 domain responsible for the interaction with the transcription factor TFIIH.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2217355636 432 CAVC-LDVYFNPYMCY----PCHHIFCEPCLRTLAKDNPSSTPCPLCRTIISR 479
Cdd:cd16573     4 CPVCkSDRYLNPDMKFlinpECYHKMCESCVDRIFTLGPAQCPYKGCGKILRK 56

RING finger, HC subclass, found in tripartite motif-containing protein TRIM4 and similar proteins; TRIM4 belongs 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. TRIM4, also known as RING finger protein 87 (RNF87), is a cytoplasmic E3 ubiquitin-protein ligase that has recently evolved and is present only in higher mammals. It transiently interacts with mitochondria, induces mitochondrial aggregation and sensitizes the cells to hydrogen peroxide (H2O2) induced death. Its interaction with peroxiredoxin 1 (PRX1) is critical for the regulation of H2O2 induced cell death. Moreover, TRIM4 functions as a positive regulator of RIG-I-mediated type I interferon induction. It regulates the K63-linked ubiquitination of RIG-1 and assembly of antiviral signaling complex at the mitochondria.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 2217355636 427 KDSYICAVCLDvYFNPYMCYPCHHIFCEPCLRTLAKDNPSSTPCPLCR 474
Cdd:cd16590     4 QEELTCPICLD-YFQDPVSIECGHNFCRGCLHRNWAPGGGPFPCPECR 50

RING finger, HC subclass, found in constitutive photomorphogenesis protein 1 (COP1) and similar proteins; COP1, also known as RING finger and WD repeat domain protein 2 (RFWD2) or RING finger protein 200 (RNF200), is a central regulator of photomorphogenic development in plants, which targets key transcription factors for proteasome-dependent degradation. It is localized predominantly in the nucleus, but may also be present in the cytosol. Mammalian COP1 functions as an E3 ubiquitin-protein ligase that interacts with Jun transcription factors and modulates their transcriptional activity. It also interacts with and negatively regulates the tumor-suppressor protein p53. Moreover, COP1 associates with COP9 signalosome subunit 6 (CSN6), and is involved in 14-3-3sigma ubiquitin-mediated degradation. The CSN6-COP1 link enhances ubiquitin-mediated degradation of p27(Kip1), a critical CDK inhibitor involved in cell cycle regulation, to promote cancer cell growth. Furthermore, COP1 functions as the negative regulator of ETV1 and influences prognosis in triple-negative breast cancer. COP1 contains an N-terminal extension, a C3HC4-type RING-HC finger, a coiled coil domain, and seven WD40 repeats. In human COP1, a classic leucine-rich NES, and a novel bipartite NLS is bridged by the RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2217355636 428 DSYICAVCLDVYFNPYMCyPCHHIFCEPCLRTLAKDNPSstpCPLCRTIIS 478
Cdd:cd16504     1 NDFLCPICFDIIKEAFVT-KCGHSFCYKCIVKHLEQKNR---CPKCNFYLT 47

Modified RING finger, HC subclass (C3HC5-type), found in mitochondrial-anchored protein ligase (MAPL) and similar proteins; MAPL, also known as MULAN, mitochondrial ubiquitin ligase activator of NFKB 1, E3 SUMO-protein ligase MUL1, E3 ubiquitin-protein ligase MUL1, growth inhibition and death E3 ligase (GIDE), putative NF-kappa-B-activating protein 266, or RING finger protein 218 (RNF218), is a multifunctional mitochondrial outer membrane protein involved in several processes specific to metazoan (multicellular animal) cells, such as NF-kappaB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. MAPL contains a unique BAM (beside a membrane)/GIDE (growth inhibition death E3 ligase) domain and a C-terminal modified cytosolic C3HC5-type RING-HC finger which 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 2217355636 432 CAVCLDvyfNPYMC--YPCHHI-FCEPCLRTLakdnPSSTPCPLCRTIISRV 480
Cdd:cd16648     4 CVICLS---NPRSCvfLECGHVcSCIECYEAL----PSPKKCPICRSFIKRV 48

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein RNFT1, RNFT2, and similar proteins; Both RNFT1 and RNFT2 are multi-pass membrane proteins containing a C3HC4-type RING-HC finger. Their biological roles remain unclear.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2217355636 431 ICAVCLDVYFNPyMCYPCHHIFCEPCL-------RTlakdnpsstpCPLCR 474
Cdd:cd16532     2 ICPICQDEFKDP-VVLRCKHIFCEDCVsewfereRT----------CPLCR 41