RING finger (Really Interesting New Gene) domain and U-box domain superfamily; 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 different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are 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 enable efficient transfer of ubiquitin from E2 to the substrates.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCKSGVDRSKVIPVY 71
Cdd:cd16744   1 FECNICLDTAKDAVVSLCGHLFCWPCLHQWLETRPNRQVCPVCKAGISRDKVIPLY 56

RING finger, HC subclass, found in RING finger protein 185 (RNF185) and similar proteins; RNF185 is an E3 ubiquitin-protein ligase of endoplasmic reticulum-associated degradation (ERAD) that targets cystic fibrosis transmembrane conductance regulator (CFTR). It controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical ERAD model substrates. It also negatively regulates osteogenic differentiation by targeting dishevelled2 (Dvl2), a key mediator of the Wnt signaling pathway, for degradation. Moreover, RNF185 regulates selective mitochondrial autophagy through interaction with the Bcl-2 family protein BNIP1. It also plays an important role in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. RNF185 contains a C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCKSGVDRSKVIPVY 71
Cdd:cd16744   1 FECNICLDTAKDAVVSLCGHLFCWPCLHQWLETRPNRQVCPVCKAGISRDKVIPLY 56

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

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 24664494  13 ESFYECNICLDTAQNAVVSMCGHLFCWPCLYQ-WILTKPDHtvCPVCKSGVDRSKVI 68
Cdd:COG5574 213 LADYKCFLCLEEPEVPSCTPCGHLFCLSCLLIsWTKKKYEF--CPLCRAKVYPKKVI 267

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 24664494    17 ECNICLD---TAQNAVVSMCGHLFCWPCLYQWILTkpdHTVCPVCK 59
Cdd:pfam13639   2 ECPICLEefeEGDKVVVLPCGHHFHRECLDKWLRS---SNTCPLCR 44

RING finger, HC subclass, found in RING finger protein 185 (RNF185) and similar proteins; RNF185 is an E3 ubiquitin-protein ligase of endoplasmic reticulum-associated degradation (ERAD) that targets cystic fibrosis transmembrane conductance regulator (CFTR). It controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical ERAD model substrates. It also negatively regulates osteogenic differentiation by targeting dishevelled2 (Dvl2), a key mediator of the Wnt signaling pathway, for degradation. Moreover, RNF185 regulates selective mitochondrial autophagy through interaction with the Bcl-2 family protein BNIP1. It also plays an important role in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. RNF185 contains a C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCKSGVDRSKVIPVY 71
Cdd:cd16744   1 FECNICLDTAKDAVVSLCGHLFCWPCLHQWLETRPNRQVCPVCKAGISRDKVIPLY 56

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 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCK 59
Cdd:cd16534   1 FECNICLDTASDPVVTMCGHLFCWPCLYQWLETRPDRQTCPVCK 44

E3 ubiquitin-protein ligase RMA2; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 24664494    4 DTFVMDTKDEsfYECNICLDTAQNAVVSMCGHLFCWPCLYQWI---------LTKPDHT----VCPVCKSGVDRSKVIPV 70
Cdd:PLN03208   9 DTTLVDSGGD--FDCNICLDQVRDPVVTLCGHLFCWPCIHKWTyasnnsrqrVDQYDHKreppKCPVCKSDVSEATLVPI 86

                         90       100
                 ....*....|....*....|.
gi 24664494   71 YARNDKRQEDPRDkTPPRPTG 91
Cdd:PLN03208  87 YGRGQKAPQSGSN-VPSRPSG 106

RING finger, HC subclass, found in peroxin-10 (PEX10) and similar proteins; PEX10, also known as peroxisome biogenesis factor 10, peroxisomal biogenesis factor 10, peroxisome assembly protein 10, or RING finger protein 69 (RNF69), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It plays an essential role in peroxisome assembly, import of target substrates, and recycling or degradation of protein complexes and amino acids. It is an essential component of the spinal locomotor circuit, and thus its mutations may be involved in peroxisomal biogenesis disorders (PBD). Mutations in human PEX10 also result in autosomal recessive ataxia. Moreover, PEX10 functions as an E3-ubiquitin ligase with an E2, UBCH5C. It mono- or poly-ubiquitinates PEX5, a key player in peroxisomal matrix protein import, in a UBC4-dependent manner, to control PEX5 receptor recycling or degradation. It also links the E2 ubiquitin conjugating enzyme PEX4 to the protein import machinery of the peroxisome.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDhtvCPVCKSGVDRSKVIPV 70
Cdd:cd16527   3 CSLCLEERRHPTATPCGHLFCWSCITEWCNEKPE---CPLCREPFQPQRLVPL 52

RING finger, HC subclass, found in breast cancer type 1 susceptibility protein (BRCA1) and similar proteins; BRCA1, also known as RING finger protein 53 (RNF53), is a RING finger protein encoded by the tumor suppressor gene BRCA1 that regulates all DNA double-strand break (DSB) repair pathways. BRCA1 is frequently mutated in patients with hereditary breast and ovarian cancer (HBOC). Its mutation is also associated with an increased risk of pancreatic, stomach, laryngeal, fallopian tube, and prostate cancer. It plays an important role in the DNA damage response signaling and has been implicated in various cellular processes such as cell cycle regulation, transcriptional regulation, chromatin remodeling, DNA DSBs, and apoptosis. BRCA1 contains an N-terminal C3HC4-type RING-HC finger, and two BRCT (BRCA1 C-terminus domain) repeats at the C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCKSGVDR 64
Cdd:cd16498  18 ECPICLELLKEPVSTKCDHQFCRFCILKLLQKKKKPAPCPLCKKSVTK 65

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 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWIltKPDHTVCPVC 58
Cdd:cd16449   1 LECPICLERLKDPVLLPCGHVFCRECIRRLL--ESGSIKCPIC 41

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 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTV-CPVC 58
Cdd:cd16536   1 PQCPICLEPPVAPRITRCGHIFCWPCILRYLSLSEKKWRkCPIC 44

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 24664494    17 ECNICLD---TAQNAVVSMCGHLFCWPCLYQWILTkpdHTVCPVCK 59
Cdd:pfam13639   2 ECPICLEefeEGDKVVVLPCGHHFHRECLDKWLRS---SNTCPLCR 44

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

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 24664494    18 CNICLDTAQNAVVSmCGHLFCWPCLYQWILTKPDHTVCP 56
Cdd:pfam13445   1 CPICLELFTDPVLP-CGHTFCRECLEEMSQKKGGKFKCP 38

RING finger, HC subclass, found in RING finger protein 213 (RNF213) and similar proteins; RNF213, also known as ALK lymphoma oligomerization partner on chromosome 17 or Moyamoya steno-occlusive disease-associated AAA+ and RING finger protein (mysterin), is an intracellular soluble protein that functions as an E3 ubiquitin-protein ligase and AAA+ ATPase, which possibly contributes to vascular development through mechanical processes in the cell. It plays a unique role in endothelial cells for proper gene expression in response to inflammatory signals from the environment. Mutations in RNF213 may be associated with Moyamoya disease (MMD), an idiopathic cerebrovascular occlusive disorder prevalent in East Asia. It also acts as a nuclear marker for acanthomorph phylogeny. RNF213 contains two tandem enzymatically active AAA+ ATPase modules and a C3HC4-type RING-HC finger. It can form a huge ring-shaped oligomeric complex.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWIltkPDHTVCPVCKSGV 62
Cdd:cd16561   4 ECSICLEDLNDPVKLPCDHVFCEECIRQWL---PGQMSCPLCRTEL 46

RING finger, HC subclass, found in Saccharomyces cerevisiae POB3/SPT16 histone-associated protein 1 (ScPSH1) and similar proteins; ScPSH1 is a Cse4-specific E3 ubiquitin ligase that interacts with the kinetochore protein Pat1 and targets the degradation of budding yeast centromeric histone H3 variant, CENP-ACse4, which is essential for faithful chromosome segregation. ScPSH1 contains a C3HC4-type RING-HC finger and a DNA directed RNA polymerase domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWiLTKPDHTVCPVCKS 60
Cdd:cd16568   6 ECIICHEYLYEPMVTTCGHTYCYTCLNTW-FKSNRSLSCPDCRT 48

RING finger, HC subclass, found in Casitas B-lineage lymphoma (Cbl) proteins; The Cbl adaptor protein family contains a small class of RING-type E3 ubiquitin ligases with oncogenic activity, which is represented by three mammalian members, c-Cbl, Cbl-b and Cbl-c, as well as two invertebrate Cbl-family proteins, D-Cbl in Drosophila and Sli-1 in C. elegans. Cbl proteins function as potent negative regulators of various signaling cascades in a wide range of cell types. They play roles in ubiquitinating activated tyrosine kinases and targeting them for degradation. D-Cbl associates with the Drosophila epidermal growth factor receptor (EGFR) and overexpression of D-Cbl in the eye of Drosophila embryos inhibits EGFR-dependent photoreceptor cell development. Sli-1 is a negative regulator of the Let-23 receptor tyrosine kinase, an EGFR homolog, in vulva development. Cbl proteins in this subfamily consist of a highly conserved N-terminal half that includes 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) and a C3HC4-type RING-HC finger, both of which are required for Cbl-mediated downregulation of RTKs, and a divergent C-terminal region.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 24664494  15 FYECNICLDTAQNAVVSMCGHLFCWPCLYQWILTkpDHTVCPVCK 59
Cdd:cd16502   1 FQLCKICAENDKDVRIEPCGHLLCTPCLTSWQDS--DGQTCPFCR 43

RING finger, HC subclass, found in Saccharomyces cerevisiae DNA repair protein RAD16, Schizosaccharomyces pombe rhp16, and similar proteins; Budding yeast RAD16, also known as ATP-dependent helicase RAD16, is encoded by a yeast excision repair gene homologous to the recombinational repair gene RAD54 and to the SNF2 gene involved in transcriptional activation. It is a component of the global genome repair (GGR) complex that promotes global genome nucleotide excision repair (GG-NER) by removing DNA damage from non-transcribing DNA. RAD16 is involved in differential repair of DNA after UV damage, and repairs preferentially the MAT-alpha locus compared with the HML-alpha locus. Fission yeast rhp16, also known as ATP-dependent helicase rhp16, is a RAD16 homolog. It is involved in GGR via nucleotide excision repair (NER), in conjunction with rhp7, after UV irradiation. Both RAD16 and rhp16 contain a C3HC4-type RING-HC finger, as well as a DEAD-like helicase domain and a helicase superfamily C-terminal domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTV-CPVC 58
Cdd:cd16567   2 VCGICHEEAEDPVVARCHHVFCRACVKEYIESAPGGKVtCPTC 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 24664494  17 ECNICLDTAQN--AVVSMCGHLFCWPCLYQWILTKPdhtVCPVCK 59
Cdd:cd16574   3 SCPICLDRFENekAFLDGCFHAFCFTCILEWSKVKN---ECPLCK 44

Zinc finger, C3HC4 type (RING finger); The C3HC4 type zinc-finger (RING finger) is a cysteine-rich domain of 40 to 60 residues that coordinates two zinc ions, and has the consensus sequence: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C where X is any amino acid. Many proteins containing a RING finger play a key role in the ubiquitination pathway.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 24664494    18 CNICLDTAQNAVVSM-CGHLFCWPCLYQWILTKpdHTVCPVC 58
Cdd:pfam00097   1 CPICLEEPKDPVTLLpCGHLFCSKCIRSWLESG--NVTCPLC 40

RING finger, HC subclass, found in RING finger protein 170 (RNF170) and similar proteins; RNF170, also known as putative LAG1-interacting protein, is an endoplasmic reticulum (ER) membrane-bound E3 ubiquitin-protein ligase that mediates ubiquitination-dependent degradation of type-I inositol 1,4,5-trisphosphate (IP3) receptors (ITPR1) via the endoplasmic-reticulum-associated protein degradation (ERAD) pathway. A point mutation (arginine to cysteine at position 199) in the RNF170 gene is linked with autosomal-dominant sensory ataxia (ADSA), a disease characterized by neurodegeneration in the posterior columns of the spinal cord. RNF170 contains a C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQ-WILTKPDHTV-CPVCKSGV 62
Cdd:cd16553   3 ECPICLQDARFPVETNCGHLFCGPCIITyWRHGSWLGAVsCPVCRQTV 50

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl-c and similar proteins; Cbl-c, also known as RING finger protein 57 (RNF57), SH3-binding protein Cbl-3, SH3-binding protein Cbl-c, or signal transduction protein Cbl-c, is an E3 ubiquitin-protein ligase expressed exclusively in epithelial cells. 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 C3HC4-type RING-HC finger, and a short proline-rich region, but lacks the ubiquitin-associated (UBA) leucine zipper motif that are present in Cbl and Cbl-b. Cbl-c acts as a regulator of epidermal growth factor receptor (EGFR)-mediated signal transduction. It also suppresses v-Src-induced transformation through ubiquitin-dependent protein degradation. Moreover, Cbl-c ubiquitinates and downregulates RETMEN2A and implicates Enigma (PDLIM7) as a positive regulator of RETMEN2A by blocking Cbl-mediated ubiquitination and degradation. The ubiquitin ligase activity of Cbl-c is increased via the interaction of its RING-HC finger domain with a LIM domain of the paxillin homolog, hydrogen peroxide induced construct 5 (Hic-5).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 24664494  12 DESFYECNICLDTAQNAVVSMCGHLFCWPCLYQWilTKPDHTVCPVCK 59
Cdd:cd16710  10 NSTFELCKICAERDKDVRIEPCGHLLCSCCLAAW--QHSDSQTCPFCR 55

RING finger, HC subclass, found in yeast Bre1 and its homologs from eukaryotes; Bre1 is an E3 ubiquitin-protein ligase that catalyzes monoubiquitination of histone H2B in concert with the E2 ubiquitin-conjugating enzyme, Rad6. The Rad6-Bre1-mediated histone H2B ubiquitylation modulates the formation of double-strand breaks (DSBs) during meiosis in yeast. it is also required, indirectly, for the methylation of histone 3 on lysine 4 (H3K4) and 79. RNF20, also known as BRE1A and RNF40, also known as BRE1B, are the mammalian homologs of Bre1. They work together to form a heterodimeric Bre1 complex that facilitate the K120 monoubiquitination of histone H2B (H2Bub1), a DNA damage-induced histone modification that is crucial for recruitment of the chromatin remodeler SNF2h to DNA double-strand break (DSB) damage sites. Moreover, the Bre1 complex acts as a tumor suppressor, augmenting expression of select tumor suppressor genes and suppressing select oncogenes. Deficiency in the mammalian histone H2B ubiquitin ligase Bre1 leads to replication stress and chromosomal instability. All subfamily members contain a C3HC4-type RING-HC finger at its C-terminus.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQWILTKpdHTVCPVCKSGVDRSKVIPV 70
Cdd:cd16499   9 CSVCNDRFKDVIITKCGHVFCNECVQKRLETR--QRKCPGCGKAFGANDVQRI 59

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
                ....*....|....*....|....*....|....*....|....*...
gi 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDhtvCPVCKSGVD 63
Cdd:cd16504   3 FLCPICFDIIKEAFVTKCGHSFCYKCIVKHLEQKNR---CPKCNFYLT 47

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 24664494  17 ECNICLDTAQNA-VVSMCGHLFCWPCLYQWILTKPdhtVCPVCK 59
Cdd:cd16506   2 TCPICLDEIQNKkTLEKCKHSFCEDCIDRALQVKP---VCPVCG 42

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
                ....*....|....*....|....*....|....*....|....*....
gi 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWIltKPDHTVCPVCKSGVDR 64
Cdd:cd16542   2 FDCAVCLEVLHQPVRTRCGHVFCRPCIATSL--RNNTWTCPYCRAYLSS 48

RING finger, HC subclass, found in RING finger protein 141 (RNF141) and similar proteins; RNF141, also known as zinc finger protein 230 (ZNF230), is a RING finger protein present primarily in the nuclei of spermatogonia, the acrosome, and the tail of spermatozoa. It may have a broad function during early development of vertebrates. It plays an important role in spermatogenesis, including spermatogenic cell proliferation and sperm maturation, as well as motility and fertilization. It also exhibits DNA binding activity. RNF141/ZNF230 gene mutations may be associated with azoospermia. RNF141 contains a C3HC4-type RING finger domain that may function as an activator module in transcription.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 24664494  17 ECNICLDtAQNAVVSMCGHLFCWPCLYQWiltKPDHTVCPVCK 59
Cdd:cd16545   2 ECCICMD-RKADLILPCAHSYCQKCIDKW---SDRHRTCPICR 40

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) and similar proteins; TRAF6, also known as interleukin-1 signal transducer or RING finger protein 85 (RNF85), is a cytoplasmic adapter protein that mediates signals induced by the tumor necrosis factor receptor (TNFR) superfamily and Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) family. It functions as a mediator involved in the activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways, as well as in IL-1R-mediated activation of NF-kappaB. TRAF6 is also an oncogene that plays a vital role in K-RAS-mediated oncogenesis. TRAF6 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 24664494  16 YECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHtvCPV 57
Cdd:cd16643   2 YECPICLMALREPVQTPCGHRFCKACILKSIREAGHK--CPV 41

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 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWIltkpDH-TVCPVCKSGV 62
Cdd:cd16514   3 ECSLCLRLLYEPVTTPCGHTFCRACLERCL----DHsPKCPLCRTSL 45

RING finger, HC subclass, found in Arabidopsis thaliana protein XB3 homolog 5 (XBAT35) and similar proteins; XBAT35, also known as ankyrin repeat domain and RING finger-containing protein XBAT35, or RING-type E3 ubiquitin transferase XBAT35, has no E3 ubiquitin-protein ligase activity observed when associated with the E2 enzyme UBC8 in vitro. It contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24664494  17 ECNICLDTAQNAVVSMCGHL-FCWPCLYQwILTKpdHTVCPVCKSGVDRskVIPVY 71
Cdd:cd23129   4 ECVVCMDAPRDAVCVPCGHVaGCMSCLKA-LMQS--SPLCPICRAPVRQ--VIKVY 54

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
                ....*....|....*....|....*....|....*....|..
gi 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCK 59
Cdd:cd16543   6 CSICLDLLKDPVTIPCGHSFCMNCITLLWDRKQGVPSCPQCR 47

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 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQwiLTKPDHTVCPVCK 59
Cdd:cd16596  12 CPICLDPFVEPVSIECGHSFCQECISQ--VGKGGGSVCPVCR 51

RING finger, HC subclass, found in protein Deltex-3-like (DTX3L) and similar proteins; DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), is a RING-domain E3 ubiquitin-protein ligase that 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. DTX3L has a unique N-terminus, but lacks the highly basic N-terminal motif and the central proline-rich motif present in other Deltex (DTX) family members, such as DTX1, DTX2, and DTX4. Moreover, its C-terminal region is highly homologous to DTX3. It includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N-terminus and further enhance self-ubiquitination.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 24664494  17 ECNICLDTAQNA-VVSMCGHLFCWPCLYQWILTKPdhtVCPVC 58
Cdd:cd16712   5 ECPICMDRISNKkVLPKCKHVFCAACIDKAMKYKP---VCPVC 44

Modified RING finger, HC subclass (C3HC5-type), found in neuralized-like protein 1A (NEURL1A) and similar proteins; NEURL1A, also known as NEURL1, NEU, neuralized 1, or RING finger protein 67 (RNF67), is a mammalian homolog of the Drosophila neuralized (D-neu) protein. 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 the medulloblastoma. NEURL1A contains 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 24664494  17 ECNICLDTAQNAVVSMCGHL-FCWPCLYQwiLTKPDHTVCPVCKSGV 62
Cdd:cd16785   6 ECTICYENAVDTVIYTCGHMcLCYACGLR--LKKMLNACCPICRRAI 50

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        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 24664494    13 ESFYECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDhtvCPVCKSGVDRSKV 67
Cdd:TIGR00599  24 DTSLRCHICKDFFDVPVLTSCSHTFCSLCIRRCLSNQPK---CPLCRAEDQESKL 75

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 24664494  15 FYECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVCK 59
Cdd:cd16586   1 FLSCGICLERYKNPKVLPCLHTFCERCLQNYIPAESLSLSCPVCR 45

first RING finger, HC subclass, found in Arabidopsis thaliana ORTHRUS and similar proteins; This subfamily includes Arabidopsis thaliana ORTHRUS 1-5. They are E3 ubiquitin-protein ligases that may participate in CpG methylation-dependent transcriptional regulation and/or epigenetic transcriptional silencing. ORTHRUS 1 mediates ubiquitination with the E2 ubiquitin-conjugating enzymes UBC11, UBC8 and UBC8 homologs (e.g. UBC10, UBC11, UBC28 and UBC29) but not with UBC27, UBC30, UBC32, UBC34 and UBC36. ORTHRUS 2 and 5 mediate ubiquitination with the E2 ubiquitin-conjugating enzyme UBC11. ORTHRUS 1 and 2 promote methylation-mediated gene silencing leading, for example, to early flowering. They can bind to CpG, CpNpG, and CpNpN DNA motifs, with a strong preference for methylated forms, and with highest affinity for CpG substrates. Members of this subfamily contain two typical C3HC4-type RING-HC fingers. This model corresponds to the first one.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWIltKPDHTVCPVCKS 60
Cdd:cd23138   4 NCSFCMQLPERPVTTPCGHNFCLKCFQKWM--GQGKKTCGTCRS 45

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl-b and similar proteins; Cbl-b, also known as Casitas B-lineage lymphoma proto-oncogene b, RING finger protein 56 (RNF56), SH3-binding protein Cbl-b, or signal transduction protein Cbl-b, has been identified as a regulator of antigen-specific, T cell-intrinsic, peripheral immune tolerance, a state also known as clonal anergy. It may inhibit activation of the p85 subunit of phosphoinositide 3-kinase (PI3K), protein kinase C-theta (PKC-theta), and phospholipase C-gamma1 (PLC-gamma1) and negatively regulates T-cell receptor-induced transcription factor nuclear factor kappaB (NF-kappaB) activation. In addition, Cbl-b may target multiple signaling molecules involved in transforming growth factor (TGF)-beta-mediated transactivation pathways. Cbl-b contains a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, is composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain), a proline rich domain, a nuclear localization signal, a C3HC4-type RING-HC finger and an ubiquitin-associated (UBA) domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 24664494  14 SFYECNICLDTAQNAVVSMCGHLFCWPCLYQWilTKPDHTVCPVCKSGVDRSKVIPV 70
Cdd:cd16709  19 TFQLCKICAENDKDVKIEPCGHLMCTSCLTAW--QESDGQGCPFCRCEIKGTEPIIV 73

RING finger, HC subclass, found in RING finger protein 220 (RNF220) and similar proteins; RNF220 is an E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of Sin3B, a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. It can also bind E2 and mediate auto-ubiquitination of itself. Moreover, RNF220 specifically interacts with beta-catenin, and enhances canonical Wnt signaling through ubiquitin-specific protease 7 (USP7)-mediated deubiquitination and stabilization of beta-catenin, which is independent of its E3 ligase activity. RNF220 contains a characteristic C3HC4-type RING-HC finger at its C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 24664494  16 YECNICLDTAQNAVVSM-CGHLFCWPClyqWILTKPDHTVCPVCKS 60
Cdd:cd16563   1 YKCLICMDSYTMPLVSIqCWHVHCEEC---WLRTLGAKKLCPQCNT 43

RING finger, HC subclass, found in RNA-binding protein MEX3B; MEX3B, also known as RING finger and KH domain-containing protein 3 (RKHD3), or RING finger protein 195 (RNF195), is an RNA-binding phosphoprotein that localizes in P-bodies and stress granules, which are two structures involved in the storage and turnover of mRNAs. It regulates the spatial organization of the Rap1 pathway that orchestrates Sertoli cell functions. It has a 3' long conserved untranslated region (3'LCU)-mediated fine-tuning system for mRNA regulation in early vertebrate development such as anteroposterior (AP) patterning and signal transduction. MEX3B contains two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. Like other MEX-3 family proteins, MEX3B shuttles between the nucleus and the cytoplasm via the CRM1-dependent export pathway.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 24664494  17 ECNICLDTAQNAVVSMCGH-LFCWPCLYQwiLTKPDHTVCPVCKSGVDRS 65
Cdd:cd16721   6 DCSICFESEVIAALVPCGHnLFCMECANR--ICEKNEPQCPVCHAAVTQA 53

RING finger, HC subclass, found in really interesting new gene proteins RING1, RING2 and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), is a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. Both RING1 and RING2 are core components of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING2 acts as the main E3 ubiquitin ligase on histone H2A of the PRC1 complex, while RING1 may rather act as a modulator of RNF2/RING2 activity. Members of this family contain a C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 24664494  18 CNICLDTAQNA-VVSMCGHLFCWPCLYQWILTKPDHtvCPVCK 59
Cdd:cd16531   4 CPICLGIIKNTmTVKECLHRFCAECIEKALRLGNKE--CPTCR 44

RING finger, HC subclass, found in tripartite motif-containing protein 35 (TRIM35) and similar proteins; TRIM35, also known as hemopoietic lineage switch protein 5 (HLS5), is a putative hepatocellular carcinoma (HCC) suppressor that inhibits phosphorylation of pyruvate kinase isoform M2 (PKM2), which is involved in aerobic glycolysis of cancer cells and further suppresses the Warburg effect and tumorigenicity in HCC. It also negatively regulates Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon production by suppressing the stability of interferon regulatory factor 7 (IRF7). Moreover, TRIM35 regulates erythroid differentiation by modulating globin transcription factor 1 (GATA-1) activity. TRIM35 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 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTvCPVCKSGVDRSK 66
Cdd:cd16599   7 CPICYEPFREAVTLRCGHNFCKGCVSRSWERQPRAP-CPVCKEASSSDD 54

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 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQwILTKPDH--TVCPVCKSG 61
Cdd:cd16612   7 CPLCLKLFQSPVTTECGHTFCQDCLSR-VPKEEDGgsTSCPTCQAP 51

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDhtvCPVCKSGVDRSK 66
Cdd:cd23148   5 RCHICKDLLKAPMRTPCNHTFCSFCIRTHLNNDAR---CPLCKAEVTESG 51

RING finger, HC subclass, found in BRCA1-associated RING domain protein 1 (BARD-1) and similar proteins; BARD-1 is a critical factor in BRCA1-mediated tumor suppression and may also serve as a target for tumorigenic lesions in some human cancers. It associates with BRCA1 (breast cancer-1) to form a heterodimeric BRCA1/BARD1 complex that is responsible for maintaining genomic stability through nuclear functions involving DNA damage signaling and repair, transcriptional regulation, and cell cycle control. The BRCA1/BARD1 complex catalyzes autoubiquitination of BRCA1 and trans ubiquitination of other protein substrates. Its E3 ligase activity is dramatically reduced in the presence of UBX domain protein 1 (UBXN1). BARD-1 contains an C3HC4-type RING-HC finger that binds BRCA1 at its N-terminus and three tandem ankyrin repeats and tandem BRCT repeat domains at its C-terminus. The BRCT repeats bind CstF-50 (cleavage stimulation factor) to modulate mRNA processing and RNAP II stability in response to DNA damage.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 24664494  13 ESFYECNICLDTAQNAV-VSMCGHLFCWPCLyqwiltkPDH--TVCPVCKsgvdrskvIPVYAR 73
Cdd:cd16496  13 ENLLRCSRCASILKEPVtLGGCEHVFCRSCV-------GDRlgNGCPVCD--------TPAWAR 61

RING finger, HC subclass, found in tripartite motif-containing protein 31 (TRIM31) and similar proteins; TRIM31 is an E3 ubiquitin-protein ligase that primarily localizes to the cytoplasm, but is also associated with the mitochondria. It can negatively regulate cell proliferation and may be a potential biomarker of gastric cancer as it is overexpressed from the early stage of gastric carcinogenesis. TRIM31 is downregulated in non-small cell lung cancer and serves as a potential tumor suppressor. It interacts with p52 (Shc) and inhibits Src-induced anchorage-independent growth. TRIM31 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
                ....*....|....*....|....*....|....*....|.
gi 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQWILTKPDHTVCPVC 58
Cdd:cd16582   4 CPICLDILQKPVTIDCGHNFCLQCITQIGETSCGFFKCPLC 44

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 24664494  18 CNICLDTAQNAVVSMCGHLFCWPCLYQWIltkPDHTVCPVCK 59
Cdd:cd16562   4 CHICLGKVRQPVICSNNHVFCSSCMDVWL---KNNNQCPACR 42

RING finger, H2 subclass, found in RING finger protein 103 (RNF103) and similar proteins; RNF103, also known as KF-1 or zinc finger protein 103 homolog (Zfp-103), is an endoplasmic reticulum (ER)-resident E3 ubiquitin-protein ligase that is widely expressed in many different organs, including brain, heart, kidney, spleen, and lung. It is involved in the ER-associated degradation (ERAD) pathway by interacting with components of the ERAD pathway, including Derlin-1 and VCP. RNF103 contains several hydrophobic regions at its N-terminal and middle regions, as well as a C-terminal C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 24664494  17 ECNICLDTAQNAVVSM---CGHLFCWPCLYQWiLTKPDHTvCPVCKSGV 62
Cdd:cd16473   6 ECAICLENYQNGDLLRglpCGHVFHQNCIDVW-LERDNHC-CPVCRWPV 52

RING finger, HC subclass, found in RING finger proteins RNF113A, RNF113B, and similar proteins; RNF113A, also known as zinc finger protein 183 (ZNF183), is an E3 ubiquitin-protein ligase that physically interacts with the E2 protein, UBE2U. A nonsense mutation in RNF113A is associated with an X-linked trichothiodystrophy (TTD). Its yeast ortholog Cwc24p is predicted to have a spliceosome function and acts in a complex with Cef1p to participate in pre-U3 snoRNA splicing, indirectly affecting pre-rRNA processing. It is also important for the U2 snRNP binding to primary transcripts and co-migrates with spliceosomes. Moreover, the ortholog of RNF113A in fruit flies may also act as a spliceosome and is hypothesized to be involved in splicing, namely within the central nervous system. The ortholog in Caenorhabditis elegans is involved in DNA repair of inter-strand crosslinks. RNF113B, also known as zinc finger protein 183-like 1, shows high sequence similarity with RNF113A. Both RNF113A and RNF113B contain a CCCH-type zinc finger, which is commonly found in RNA-binding proteins involved in splicing, and a C3HC4-type RING-HC finger, which is frequently found in E3 ubiquitin ligases.

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                ....*....|....*....|....*....|....*....|...
gi 24664494  18 CNICLDTAQNAVVSMCGHLFCWPClyqwILTKPDHTV-CPVCK 59
Cdd:cd16539   8 CFICRKPFKNPVVTKCGHYFCEKC----ALKHYRKSKkCFVCG 46

RING finger, HC subclass, found in ligand of Numb protein LNX3, LNX4, 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 the substrate-binding. This family corresponds to LNX3/LNX4-like proteins, which contains a C3HC4-type RING-HC finger and two PDZ domains.

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                ....*....|....*....|....*....|....*....|
gi 24664494  17 ECNICLDTAQNAVVSMCGHLFCWPCLYQWILtkpDHTVCP 56
Cdd:cd16512   2 KCKLCLGVLEEPLATPCGHVFCAGCVLPWVV---RNGSCP 38

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 24664494  17 ECNICLDTAQNAVVSMCGHL-FCWPCLYQwilTKPDHTVCPVCKS 60
Cdd:cd16647   3 ECVICYERPVDTVLYRCGHMcMCYDCALQ---LKRRGGSCPICRA 44

RING finger, HC subclass, found in Dictyostelium discoideum Ras guanine nucleotide exchange factor O (RasGEFO) and similar proteins; RasGEFO, also known as RasGEF domain-containing protein O, functions as a Ras guanine-nucleotide exchange factor (RasGEFs), activating Ras by catalyzing the replacement of GDP with GTP. RasGEFs are particularly important for signaling in development and chemotaxis in many organisms, including Dictyostelium. RasGEFO contains a C3HC4-type RING-HC finger that may be responsible for E3 ubiquitin ligase activity.

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                ....*....|....*....|....*....|....*....|....*....|....*..
gi 24664494  10 TKDESFYECNICLDT-AQNAVVSMCGHLFCWPCLYQWIltkpDHTVCPVCKSGVDRS 65
Cdd:cd16507   4 LNLLQSLTCGICQNLfKDPNTLIPCGHAFCLDCLTTNA----SIKNCIQCKVEYTTY 56