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 20130141   99 PPNCAICLSRCRR-KCFTDSCMHQFCFKCLCEWSKIKPECPLCKQPF 144
Cdd:cd16574    1 DSSCPICLDRFENeKAFLDGCFHAFCFTCILEWSKVKNECPLCKQPF 47

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 20130141   99 PPNCAICLSRCRR-KCFTDSCMHQFCFKCLCEWSKIKPECPLCKQPF 144
Cdd:cd16574    1 DSSCPICLDRFENeKAFLDGCFHAFCFTCILEWSKVKNECPLCKQPF 47

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 20130141     102 CAICLSRCRRKCFTDSCMHQFCFKCLCEW-SKIKPECPLC 140
Cdd:smart00184    1 CPICLEEYLKDPVILPCGHTFCRSCIRKWlESGNNTCPIC 40

RING-finger-containing E3 ubiquitin ligase [Signal transduction mechanisms];

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCKQPFR 145
Cdd:COG5432   28 CRICDCRISIPCET-TCGHTFCSLCIRRHLGTQPFCPVCREDPC 70

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 20130141   99 PPNCAICLSRCRR-KCFTDSCMHQFCFKCLCEWSKIKPECPLCKQPF 144
Cdd:cd16574    1 DSSCPICLDRFENeKAFLDGCFHAFCFTCILEWSKVKNECPLCKQPF 47

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.

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                 ....*....|....*....|....*....|....*....|....*.
gi 20130141  100 PNCAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCKQPFR 145
Cdd:cd16527    1 RKCSLCLEERRHPTAT-PCGHLFCWSCITEWCNEKPECPLCREPFQ 45

RING finger, HC subclass, found in RING finger protein 8 (RNF8) and similar proteins; RNF8 is a telomere-associated E3 ubiquitin-protein ligase that plays an important role in DNA double-strand break (DSB) repair via histone ubiquitination. It is localized in the nucleus and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3), but not with other E2s (UbcH5, UbcH7, UbcH10, hCdc34, and hBendless). It recruits UBC13 for lysine 63-based self polyubiquitylation. Its deficiency causes neuronal pathology and cognitive decline, and its loss results in neuron degeneration. RNF8, together with RNF168, catalyzes a series of ubiquitylation events on substrates such as H2A and H2AX, with the H2AK13/15 ubiquitylation being particularly important for recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of DSBs. RNF8 mediates the ubiquitination of gammaH2AX, and recruits 53BP1 and BRCA1 to DNA damage sites which promotes DNA damage response (DDR) and inhibits chromosomal instability. Moreover, RNF8 interacts with retinoid X receptor alpha (RXR alpha) and enhances its transcription-stimulating activity. It also regulates the rate of exit from mitosis and cytokinesis. RNF8 contains an N-terminal forkhead-associated (FHA) domain and a C-terminal C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 20130141  102 CAICLSRCRrKCFTDSCMHQFCFKCLCEWSKIKPECPLCKQPFRTIIHNvRTLDDY 157
Cdd:cd16535    4 CSICSELFI-EAVTLNCSHSFCSYCITEWMKRKKECPICRKPITSKTRS-LVLDNC 57

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.

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                   ....*....|....*....|....*....|....*....|
gi 20130141    102 CAICLSRCRRKCFTDSCMHQFCFKCLCEW-SKIKPECPLC 140
Cdd:pfam00097    1 CPICLEEPKDPVTLLPCGHLFCSKCIRSWlESGNVTCPLC 40

Modified RING finger, HC subclass (C3HC3D-type), found in SR-related and CTD-associated factor 11 (SCAF11) and similar proteins; SCAF11, also known as CTD-associated SR protein 11 (CASP11), renal carcinoma antigen NY-REN-40, SC35-interacting protein 1 (Sip1), Serine/arginine-rich splicing factor 2 (SRSF2)-interacting protein, or splicing regulatory protein 129 (SRrp129), is a novel arginine-serine-rich (RS) domain-containing protein essential for pre-mRNA splicing. It functions as an auxiliary splice factor interacting with the spliceosomal component SC35, promoting RNAPII elongation. In addition to SR proteins, such as SC35, ASF/SF2, SRp75, and SRp20, SCAF11 also associates with U1-70K and U2AF65, proteins associated with 5' and 3' splice sites, respectively. SCAF11 contains an N-terminal modified C3HC3D-type RING-HC finger, an internal serine-arginine rich domain (SR domain), and a C-terminal SRI domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 20130141  102 CAICLSRCRRK--CFTDSCMHQFCFKCLCEWSKIKPECPLCKQPFRTI 147
Cdd:cd16636    3 CPICLNCLLEQevAFPENCSHVFCLTCILKWAETVTSCPIDRKPFQAV 50

Modified RING finger, HC subclass (C3HC3D-type), found in PHD and RING finger domain-containing protein 1 (PHRF1) and similar proteins; PHRF1, also known as KIAA1542, or CTD-binding SR-like protein rA9, is a ubiquitin ligase which induces the ubiquitination of TGIF (TG-interacting factor) at lysine 130. It acts as a tumor suppressor that promotes the transforming growth factor (TGF)-beta cytostatic program through selective release of TGIF-driven promyelocytic leukemia protein (PML) inactivation. PHRF1 contains a plant homeodomain (PHD) finger and a modified C3HC3D-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 20130141  101 NCAICLSRcrrkcFTD-------SCMHQFCFKCLCEWSKIKPECPLCKQPF 144
Cdd:cd16635    6 SCPICLNT-----FRDqavgtpeSCDHIFCLDCILEWSKNANTCPVDRIVF 51

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.

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                 ....*....|....*....|....*....|....*....|....*....|...
gi 20130141  102 CAICLSRcrrkcFTD----SCMHQFCFKCLCEWSKIKP----ECPLCKQPFRT 146
Cdd:cd16609    6 CSICLGL-----YQDpvtlPCQHSFCRACIEDHWRQKDegsfSCPECRAPFPE 53

RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*....|...
gi 20130141   99 PPNCAICLS--------RCRRKCFTDSCMHQFCFKCLCEWSKIKPECPLCKQP 143
Cdd:cd23117    4 SVDCVICMSdielpstnSVRRDYMVTPCNHIFHTNCLERWMDIKLECPTCRRP 56

RING finger, H2 subclass, found in RING finger proteins RNF24, RNF122, and similar proteins; This subfamily includes RNF24, RNF122, and similar proteins. RNF24 is an intrinsic membrane protein localized in the Golgi apparatus. It specifically interacts with the ankyrin-repeats domains (ARDs) of TRPC1, -3, -4, -5, -6, and -7, and affects TRPC intracellular trafficking without affecting their activity. RNF122 is a RING finger protein associated with HEK 293T cell viability. It is localized to the endoplasmic reticulum (ER) and the Golgi apparatus, and overexpressed in anaplastic thyroid cancer cells. RNF122 functions as an E3 ubiquitin ligase that can ubiquitinate itself and undergo degradation through its RING finger in a proteasome-dependent manner. Both RNF24 and RNF122 contain an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*..
gi 20130141  102 CAICLSRCRRK-----CftdSCMHQFCFKCLCEWSKIKPECPLCKQP 143
Cdd:cd16469    3 CAVCLEEFKLKeelgvC---PCGHAFHTKCLKKWLEVRNSCPICKSP 46

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3) and similar proteins; DTX3, also known as RING finger protein 154 (RNF154), is an E3 ubiquitin-protein ligase that belongs to the Deltex (DTX) family. In contrast to other DTXs, DTX3 does not contain two N-terminal Notch-binding WWE domains, but a short unique N-terminal domain, suggesting it does not interact with the intracellular domain of Notch. Its C-terminal region includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain.

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                 ....*....|....*....|....*....|....*....|....*....|
gi 20130141  101 NCAICLSRCRRKCFTDSCMHQFCFKCLCEWSKIKPECPLCKQPFRTIIHN 150
Cdd:cd16711    3 TCPICLGEIQNKKTLDKCKHSFCEDCITRALQVKKACPMCGEFYGQLIGN 52

RING finger, H2 subclass, found in Arabidopsis thaliana RING-H2 zinc finger protein RHF2A and similar proteins; RHF2A is an E3 ubiquitin-protein ligase involved in the positive regulation of the gametogenesis progression. It is required for the degradation of KRP6, a cyclin-dependent kinase inhibitor which accumulates during meiosis and blocks the progression of subsequent mitoses during gametophytes development. It functions in association with RHF1A. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*...
gi 20130141  102 CAICLSRCrrkCFTD-----SCMHQFCFKCLCEWSKIKPECPLCKQPF 144
Cdd:cd23122   14 CSICLESF---CEADpatvtSCKHEYHLQCILEWSQRSKECPMCWQAL 58

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.

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                 ....*....|....*....|....*....|....*....|....*...
gi 20130141  102 CAIClSRCRRKCFTDSCMHQFCFKCLCEWSKIKPE--CPLCKQPFRTI 147
Cdd:cd16568    7 CIIC-HEYLYEPMVTTCGHTYCYTCLNTWFKSNRSlsCPDCRTKITTQ 53

RING finger, H2 subclass, found in RING finger protein 122 (RNF122) and similar proteins; RNF122 is a RING finger protein associated with HEK 293T cell viability. It is localized to the endoplasmic reticulum (ER) and the Golgi apparatus, and overexpressed in anaplastic thyroid cancer cells. RNF122 functions as an E3 ubiquitin ligase that can ubiquitinate itself and undergo degradation through its RING finger in a proteasome-dependent manner. It interacts with calcium-modulating cyclophilin ligand (CAML), which is not a substrate, but a stabilizer of RNF122. RNF122 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....
gi 20130141  102 CAICLS--RCRRKCFTDSCMHQFCFKCLCEWSKIKPECPLCKQP 143
Cdd:cd16676    3 CAVCLEdfKTKDELGVLPCQHAFHRKCLVKWLEIRCVCPMCNKP 46

RING finger, HC subclass, found in Saccharomyces cerevisiae increased recombination centers protein 20 (IRC20) and similar proteins; IRC20 is an uncharacterized ATP-dependent helicase that is probably involved in a pathway contributing to genomic integrity. IRC20 contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|.
gi 20130141  101 NCAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCK 141
Cdd:cd23135    5 SCSICFSEIRSGAIL-KCGHFFCLSCIASWLREKSTCPLCK 44

RING finger, HC subclass, found in RING finger protein 222 (RNF222) and similar proteins; RNF222 is an uncharacterized C3HC4-type RING-HC finger-containing protein. It may function as an E3 ubiquitin-protein ligase.

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gi 20130141  102 CAICLSRCRRKCFTDSCMHQFCFKCLcewSKIKP----ECPLCKQP 143
Cdd:cd16564    3 CPVCYEDFDDAPRILSCGHSFCEDCL---VKQLVsmtiSCPICRRV 45

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

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gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKP---ECPLCK 141
Cdd:cd16743    3 CNICLETARDAVVS-LCGHLFCWPCLHQWLETRPerqECPVCK 44

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

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                 ....*....|....*....|....*....|....*....|...
gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKP---ECPLCK 141
Cdd:cd16534    3 CNICLDTASDPVVT-MCGHLFCWPCLYQWLETRPdrqTCPVCK 44

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.

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                 ....*....|....*....|....*....|....*....|...
gi 20130141  102 CAICLSRCRRKCFTDSCMHQFCFKCLCEW-SKIKPECPLCKQP 143
Cdd:cd16531    4 CPICLGIIKNTMTVKECLHRFCAECIEKAlRLGNKECPTCRKH 46

RING finger, HC subclass, found in tripartite motif-containing protein 26 (TRIM26) and similar proteins; TRIM26, also known as acid finger protein (AFP), RING finger protein 95 (RNF95), or zinc finger protein 173 (ZNF173), is an E3 ubiquitin-protein ligase that negatively regulates interferon-beta production and antiviral response through polyubiquitination and degradation of nuclear transcription factor IRF3. It functions as an important regulator for RNA virus-triggered innate immune response by bridging TBK1 to NEMO (NF-kappaB essential modulator, also known as IKKgamma) and mediating TBK1 activation. It also acts as a novel tumor suppressor of hepatocellular carcinoma by regulating cancer cell proliferation, colony forming ability, migration, and invasion. TRIM26 belongs 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, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 20130141  102 CAICLSRCRRKCFTDsCMHQFCFKCLCEWSKIK-----PECPLCKQPFR 145
Cdd:cd16598    7 CSICLDYLRDPVTID-CGHNFCRSCITDYCPISggherPVCPLCRKPFK 54

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.

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                 ....*....|....*....|....*....|....*....|
gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCK 141
Cdd:cd16742   16 CAICQAEFREPLIL-ICQHVFCEECLCLWFDRERTCPLCR 54

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.

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                 ....*....|....*....|....*....|....*....|....*
gi 20130141  102 CAICLSRCRRKCFTD--SCMHQFCFKCLCEW-SKIKPECPLCKQP 143
Cdd:cd16473    7 CAICLENYQNGDLLRglPCGHVFHQNCIDVWlERDNHCCPVCRWP 51

RING finger, HC subclass, found in RING finger protein 151 (RNF151) and similar proteins; RNF151 is a testis-specific RING finger protein that interacts with dysbindin, a synaptic and microtubular protein that binds brain snapin, a SNARE-binding protein that mediates intracellular membrane fusion in both neuronal and non-neuronal cells. Thus, it may be involved in acrosome formation of spermatids by interacting with multiple proteins participating in membrane biogenesis and microtubule organization. RNF151 contains a C3HC4-type RING finger domain, a putative nuclear localization signal (NLS), and a TNF receptor associated factor (TRAF)-type zinc finger domain.

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                 ....*....|....*....|....*....|....*....|....
gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCKQPFR 145
Cdd:cd16547    6 CSICHGVLRCPVRL-SCSHIFCKKCILQWLKRQETCPCCRKEVK 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 20130141  102 CAICLSRcrRKCFTDSCMHQFCFKCLCEWSKIKPECPLCK 141
Cdd:cd16545    3 CCICMDR--KADLILPCAHSYCQKCIDKWSDRHRTCPICR 40

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 20130141   98 PPPNCAIClsrcrRKCFTD----SCMHQFCFKCLCEWSKIKPECPLCKQP 143
Cdd:cd16539    4 LPFACFIC-----RKPFKNpvvtKCGHYFCEKCALKHYRKSKKCFVCGKQ 48

Modified RING finger, HC subclass (C2H2C4-type), found in E3 ubiquitin-protein ligase MDM2, protein MDM4 and similar proteins; MDM2 (also known as HDM2) and MDM4 (also known as MDMX or HDMX) are the primary p53 tumor suppressor negative regulators. They have non-redundant roles in the regulation of p53. MDM2 mainly functions to control p53 stability, while MDM4 controls p53 transcriptional activity. Both MDM2 and MDM4 contain an N-terminal p53-binding domain, a RanBP2-type zinc finger (zf-RanBP2) domain near the central acidic region, and a C-terminal modified C2H2C4-type RING-HC finger. Mdm2 can form homo-oligomers through its RING domain and displays E3 ubiquitin ligase activity that catalyzes the attachment of ubiquitin to p53 as an essential step in the regulation of its levels in cells. Despite its RING domain and structural similarity with MDM2, MDM4 does not homo-oligomerize and lacks ubiquitin-ligase function, but inhibits the transcriptional activity of p53. In addition, both their RING domains are responsible for the hetero-oligomerization, which is crucial for the suppression of P53 activity during embryonic development and the recruitment of E2 ubiquitin-conjugating enzymes. Moreover, MDM2 and MDM4 can be phosphorylated and destabilized in response to DNA damage stress. In response to ribosomal stress, MDM2-mediated p53 ubiquitination and degradation can be inhibited through the interaction with ribosomal proteins L5, L11, and L23. However, MDM4 is not bound to ribosomal proteins, suggesting its different response to regulation by small basic proteins such as ribosomal proteins and ARF.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 20130141  102 CAICLSRCRRKCFTDSCM-HQF-CFKCLCEWSKIKPECPLCKQPFRTIIH 149
Cdd:cd16646    3 CVICLSRPRTAAIVHGKTgHQVaCYTCAKKLKRRGKPCPVCRRPIQNVIK 52

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 20130141  102 CAICLSRCRRKCFTDSCMHQFCFKCLCE-WSKIKPECPLCKQP 143
Cdd:cd16544    5 CPVCQEVLKDPVELPPCRHIFCKACILLaLRSSGARCPLCRGP 47

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.

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                 ....*....|....*....|....*....|....*....|....
gi 20130141  100 PNCAICLSRCRRK-CFTdsCMHQFCFKCLCEWSKIKPECPLCKQ 142
Cdd:cd16561    3 QECSICLEDLNDPvKLP--CDHVFCEECIRQWLPGQMSCPLCRT 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.

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                 ....*....|....*....|....*....|....*....|...
gi 20130141  102 CAICLSRCRrKCFTDSCMHQFCFKCLCEWSKIKPE---CPLCK 141
Cdd:cd16744    3 CNICLDTAK-DAVVSLCGHLFCWPCLHQWLETRPNrqvCPVCK 44

RING finger, HC subclass, found in Arabidopsis thaliana protein BREAST CANCER SUSCEPTIBILITY 1 homolog (AtBRCA1) and similar proteins; AtBRCA1 plays a role in DNA repair and in cell-cycle control. It is required for the repair of DNA double-strand breaks (DSBs), both natural and induced by genotoxic stress, by homologous recombination (HR). AtBRCA1 contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|..
gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCKQP 143
Cdd:cd23147    7 CPICLSLFKSAANL-SCNHCFCAGCIGESLKLSAICPVCKIP 47

RING finger, HC subclass, found in tripartite motif-containing protein 62 (TRIM62) and similar proteins; TRIM62, also known as Ductal Epithelium Associated Ring Chromosome 1 (DEAR1), is a cytoplasmic E3 ubiquitin-protein ligase that was identified as a dominant regulator of acinar morphogenesis in the mammary gland. It is implicated in the inflammatory response of immune cells by regulating the Toll-like receptor 4 (TLR4) signaling pathway, leading to increased activity of the activator protein 1 (AP-1) transcription factor in primary macrophages. It is also involved in muscular protein homeostasis, especially during inflammation-induced atrophy, and may play a role in the pathogenesis of ICU-acquired weakness (ICUAW) by activating and maintaining inflammation in myocytes. Moreover, TRIM62 facilitates K27-linked poly-ubiquitination of CARD9 and also regulates CARD9-mediated anti-fungal immunity and intestinal inflammation. It also functions as a chromosome 1p35 tumor suppressor and negatively regulates transforming growth factor beta (TGFbeta)-driven epithelial-mesenchymal transition (EMT) by binding to and promoting the ubiquitination of SMAD3, a major effector of TGFbeta-mediated EMT. TRIM62 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 20130141  102 CAICLSrcrrkCFTD----SCMHQFCFKCLCE-WSKIKP-ECPLCKQPF 144
Cdd:cd16608    9 CSICLS-----IYQDpvslGCEHYFCRQCITEhWSRSEHrDCPECRRTF 52

RING finger, HC subclass, found in radiation sensitivity protein 5 (RAD5) and similar proteins; RAD5, also known as revertibility protein 2 (REV2), or DNA repair protein RAD5, is a probable helicase, and a member of the UBC2/RAD6 epistasis group. It functions with the DNA repair protein RAD18 in error-free postreplication DNA repair. It is involved in the maintenance of wild-type rates of instability of simple repetitive sequences such as poly(GT) repeats. It may also be involved in maintaining a balance which acts in favor of error-prone non-homologous joining during DNA double-strand breaks repairs. It recruits the UBC13-MMS2 dimer to chromatin for DNA repair. RAD5 contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|....*
gi 20130141   98 PPPNCAICLSRC---RRKCFTDsCMHQFCFKCLCEW------SKIKPECPLCKQP 143
Cdd:cd23131    2 IEVECSICTQEPievGEVVFTE-CGHSFCEDCLLEYiefqnkKKLDLKCPNCREP 55

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.

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                 ....*....|....*....|....*....|....*....|...
gi 20130141  101 NCAICLsRCRRKCFTDSCMHQFCFKCLCEWSKIKPECPLCKQP 143
Cdd:cd16514    3 ECSLCL-RLLYEPVTTPCGHTFCRACLERCLDHSPKCPLCRTS 44

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

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gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCKQPFR 145
Cdd:cd23148    6 CHICKDLLKAPMRT-PCNHTFCSFCIRTHLNNDARCPLCKAEVT 48

RING finger, HC subclass, found in mind bomb MIB1, MIB2, RGLG1, RGLG2, and similar proteins; MIBs are large, multi-domain E3 ubiquitin-protein ligases that promote ubiquitination of the cytoplasmic tails of Notch ligands. They are also responsible for TBK1 K63-linked ubiquitination and activation, promoting interferon production and controlling antiviral immunity. Moreover, MIBs selectively control responses to cytosolic RNA and regulate type I interferon transcription. Both MIB1 and MIB2 have similar domain architectures, which consist of two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region, where MIB1 and MIB2 contain three and two C3HC4-type RING-HC fingers, respectively. This model corresponds to the third RING-HC finger of MIB1, as well as the second RING-HC finger of MIB2. In addition to MIB1 and MIB2, the RING-HC fingers of RING domain ligase RGLG1, RGLG2 and similar proteins from plant are also included in this model. RGLG1 is a ubiquitously expressed E3 ubiquitin-protein ligase that interacts with UBC13 and, together with UBC13, catalyzes the formation of K63-linked polyubiquitin chains, which is involved in DNA damage repair. RGLG1 mediates the formation of canonical, K48-linked polyubiquitin chains that target proteins for degradation. It also regulates apical dominance by acting on the auxin transport proteins abundance. RGLG1 has overlapping functions with its closest sequelog, RGLG2. They both function as RING E3 ligases that interact with ethylene response factor 53 (ERF53) in the nucleus and negatively regulate the plant drought stress response. All RGLG proteins contain a Von Willebrand factor type A (vWA) domain and a C3HC4-type RING-HC finger.

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gi 20130141  100 PNCAICLSRCRRKCFtdSCMHQFCFKClcewSKIKPECPLCKQP 143
Cdd:cd16520    1 ILCPICMERKKNVVF--LCGHGTCQKC----AEKLKKCPICRKP 38

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.

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                 ....*....|....*....|....*....|....*....|....*..
gi 20130141  102 CAICLSRCRRKCFTdSCMHQFCFKCLCEWSKIKPECPLCkqpfRTII 148
Cdd:cd16741   17 CAICQAEFRKPILL-ICQHVFCEECISLWFNREKTCPLC----RTVI 58

RING finger, H2 subclass, found in RING finger proteins RNF111, RNF165, and similar proteins; The family includes RING finger proteins RNF111, RNF165, and similar proteins. RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It also interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. The N-terminal half of RNF111 harbors three SUMO-interacting motifs (SIMs). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. Both RNF165 and RNF111 contain a C-terminal C3H2C3-type RING-H2 finger.

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gi 20130141  101 NCAICLS------RCRRKcftdSCMHQFCFKCLCEWSKIKPECPLCK 141
Cdd:cd16474    2 KCTICLSdfeegeDVRRL----PCMHLFHQECVDQWLSTNKRCPICR 44

RING finger, HC subclass, found in tripartite motif-containing protein 47 (TRIM47) and similar proteins; TRIM47, also known as gene overexpressed in astrocytoma protein (GOA) or RING finger protein 100 (RNF100), 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, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. It plays an important role in the process of dedifferentiation that is associated with astrocytoma tumorigenesis. This subfamily also includes RING finger protein 135 (RNF135). RNF135, also known as RIG-I E3 ubiquitin ligase (REUL) or Riplet, is a widely expressed E3 ubiquitin-protein ligase that consists of an N-terminal C3HC4-type RING-HC finger and C-terminal B30.2/SPRY and PRY motifs, but lacks the B-box and coiled-coil domains that are also typically present in TRIM proteins. RNF135 serves as a specific retinoic acid-inducible gene-I (RIG-I)-interacting protein that ubiquitinates RIG-I and specifically stimulates RIG-I-mediated innate antiviral activity to produce antiviral type-I interferon (IFN) during the early phase of viral infection. It also has been identified as a bio-marker and therapy target of glioblastoma. It associates with the ERK signal transduction pathway and plays a role in glioblastoma cell proliferation, migration and cell cycle.

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                 ....*....|....*....|....*....|....*....|....*...
gi 20130141  102 CAICLSRCRrKCFTDSCMHQFCFKCL-CEWSKIKP---ECPLCKQPFR 145
Cdd:cd16604    3 CPICLDLLK-DPVTLPCGHSFCMGCLgALWGAGRGgraSCPLCRQTFP 49

RING finger, HC subclass, found in Arabidopsis thaliana proteolysis 1 protein (PRT1) and similar proteins; PRT1, also called RING-type E3 ubiquitin transferase PRT1, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of target proteins. It functions in the N-end rule pathway of protein degradation, where it specifically recognizes and ubiquitinates proteins with an N-terminal bulky aromatic amino acid (Phe). It does not act on aliphatic hydrophobic and basic N-terminal residues (Arg or Leu) containing proteins. PRT1 contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*
gi 20130141  102 CAICLSRCRrKCFTDSCMHQFCFKCL--CEWSKIKPECPLCKQPF 144
Cdd:cd23132    5 CCICLDLLY-KPVVLECGHVFCFWCVhrCMNGYDESHCPLCRRPY 48

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

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gi 20130141  101 NCAICLSrcrrkCFTD----SCMHQFCFKCL--CeWSKikPE----CPLCKQPFR 145
Cdd:cd16594    7 TCPICLD-----YFTDpvtlDCGHSFCRACIarC-WEE--PEtsasCPQCRETCP 53

RING finger, HC subclass, found in Ret finger protein-like 4B (RFPL4B) and similar proteins; RFPL4B, also called RING finger protein 211 (RNF211), is an uncharacterized RING finger protein containing a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....
gi 20130141  102 CAICLSrcrrkCFTD----SCMHQFCFKCLCEWSKIKPE----CPLCKQ 142
Cdd:cd16623   11 CPICLD-----FFSHpislSCAHIFCFDCIQKWMTKREDsiltCPLCRK 54

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.

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                 ....*....|....*....|....*....|....*....|....*....|
gi 20130141  102 CAICLSRCRRKCFTDSCMHQFCFKCLCEWSK---IKPECPLCKQPFRTII 148
Cdd:cd16554    5 CPVCLDLYYDPYMCYPCGHIFCEPCLRQLAKsspKNTPCPLCRTTIRRVF 54

RING finger, H2 subclass, found in Saccharomyces cerevisiae RING-H2 zinc finger protein RHA2B and similar proteins; RHA2B is an E3 ubiquitin-protein ligase involved in the positive regulation of abscisic acid (ABA) signaling and responses to salt and osmotic stresses during seed germination and early seedling development. It acts additively with RHA2A in regulating ABA signaling and drought response. RHA2B contains a C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*.
gi 20130141  101 NCAICLSRCRRKCFTDS--CMHQFCFKCLCEWSK-IKPECPLCKQP 143
Cdd:cd23123    2 DCCICLDKLKTGEEVKKldCRHKFHKQCIEGWLKhLNFNCPLCRSP 47