RING finger, H2 subclass, found in synoviolin and similar proteins; Synoviolin, also known as synovial apoptosis inhibitor 1 (Syvn1), Hrd1, or Der3, is an endoplasmic reticulum (ER)-anchoring E3 ubiquitin ligase that functions as a suppressor of ER stress-induced apoptosis and plays a role in homeostasis maintenance. It also targets tumor suppressor gene p53 for proteasomal degradation, suggesting crosstalk between ER associated degradation (ERAD) and p53 mediated apoptotic pathway under ER stress. Moreover, synoviolin controls body weight and mitochondrial biogenesis through negative regulation of the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1beta. It upregulates amyloid beta production by targeting a negative regulator of gamma-secretase, Retention in endoplasmic reticulum 1 (Rer1), for degradation. It is also involved in the degradation of endogenous immature nicastrin, and affects amyloid beta-protein generation. Moreover, synoviolin is highly expressed in rheumatoid synovial cells and may be involved in the pathogenesis of rheumatoid arthritis (RA). It functions as an anti-apoptotic factor that is responsible for the outgrowth of synovial cells during the development of RA. It promotes inositol-requiring enzyme 1 (IRE1) ubiquitination and degradation in synovial fibroblasts with collagen-induced arthritis. Furthermore, the upregulation of synoviolin may represent a protective response against neurodegeneration in Parkinson's disease (PD). In addition, synoviolin is involved in liver fibrogenesis. Synoviolin contains a C3H2C2-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 28571958 286 DNICIICREDMVNHSKKLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16479   1 DNTCIICREEMTVGAKKLPCGHIFHLSCLRSWLQRQQTCPTCR 43

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 28571958    289 CIICREDMVNHSKKLPCGHIFHTTCLRSWF-QRQQTCPTC 327
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWLeSGNNTCPIC 40

RING finger, H2 subclass, found in synoviolin and similar proteins; Synoviolin, also known as synovial apoptosis inhibitor 1 (Syvn1), Hrd1, or Der3, is an endoplasmic reticulum (ER)-anchoring E3 ubiquitin ligase that functions as a suppressor of ER stress-induced apoptosis and plays a role in homeostasis maintenance. It also targets tumor suppressor gene p53 for proteasomal degradation, suggesting crosstalk between ER associated degradation (ERAD) and p53 mediated apoptotic pathway under ER stress. Moreover, synoviolin controls body weight and mitochondrial biogenesis through negative regulation of the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1beta. It upregulates amyloid beta production by targeting a negative regulator of gamma-secretase, Retention in endoplasmic reticulum 1 (Rer1), for degradation. It is also involved in the degradation of endogenous immature nicastrin, and affects amyloid beta-protein generation. Moreover, synoviolin is highly expressed in rheumatoid synovial cells and may be involved in the pathogenesis of rheumatoid arthritis (RA). It functions as an anti-apoptotic factor that is responsible for the outgrowth of synovial cells during the development of RA. It promotes inositol-requiring enzyme 1 (IRE1) ubiquitination and degradation in synovial fibroblasts with collagen-induced arthritis. Furthermore, the upregulation of synoviolin may represent a protective response against neurodegeneration in Parkinson's disease (PD). In addition, synoviolin is involved in liver fibrogenesis. Synoviolin contains a C3H2C2-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 28571958 286 DNICIICREDMVNHSKKLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16479   1 DNTCIICREEMTVGAKKLPCGHIFHLSCLRSWLQRQQTCPTCR 43

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 28571958   287 NICIICREDMVNHSK--KLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:pfam13639   1 DECPICLEEFEEGDKvvVLPCGHHFHRECLDKWLRSSNTCPLCR 44

H2 subclass of RING (RING-H2) fingers 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 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). This family corresponds to the H2 subclass of RING (RING-H2) finger proteins that are characterized by containing C3H2C3-type canonical RING-H2 fingers or noncanonical RING-H2 finger variants, including C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type modified RING-H2 fingers. The canonical RING-H2 finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-H-X2-C-X(4-48)-C-X2-C, X is any amino acid and the number of X residues varies in different fingers. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-H2 finger 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 serves as a scaffold 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 28571958 289 CIICREDMV--NHSKKLPCGHIFHTTCLRSWFQ-RQQTCPTCR 328
Cdd:cd16448   1 CVICLEEFEegDVVRLLPCGHVFHLACILRWLEsGNNTCPLCR 43

RING finger, H2 subclass, found in the PA-TM-RING ubiquitin ligase family; The PA-TM-RING family represents a group of transmembrane-type E3 ubiquitin ligases, which has been characterized by an N-terminal transient signal peptide, a PA (protease-associated) domain, a TM (transmembrane) domain, as well as a C-terminal C3H2C3-type RING-H2 finger domain. It includes RNF13, RNF167, ZNRF4 (zinc and RING finger 4), GRAIL (gene related to anergy in lymphocytes)/RNF128, RNF130, RNF133, RNF148, RNF149 and RNF150 (which are more closely related), as well as RNF43 and ZNRF3, which have substantially longer C-terminal tail extensions compared with the others. PA-TM-RING proteins are expressed at low levels in all mammalian tissues and species, but they are not present in yeast. They play a common regulatory role in intracellular trafficking/sorting, suggesting that abrogation of their function may result in dysregulation of cellular signaling events in cancer.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 28571958 289 CIICREDMVNHSK--KLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16454   2 CAICLEEFKEGEKvrVLPCNHLFHKDCIDPWLEQHNTCPLCR 43

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 28571958    289 CIICREDMVNHSKKLPCGHIFHTTCLRSWF-QRQQTCPTC 327
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWLeSGNNTCPIC 40

RING finger, H2 subclass, found in RING finger protein 11 (RNF11) and similar proteins; RNF11 is an E3 ubiquitin-protein ligase that acts both as an adaptor and a modulator of itch-mediated control of ubiquitination events underlying membrane traffic. It acts downstream of an enzymatic cascade for the ubiquitination of specific substrates. It is also a molecular adaptor of homologous to E6-associated protein C-terminus (HECT)-type ligases. RNF11 has been implicated in the regulation of several signaling pathways. It enhances transforming growth factor receptor (TGFR) signaling by both abrogating Smurf2-mediated receptor ubiquitination and by promoting the Smurf2-mediated degradation of AMSH (associated molecule with the SH3 domain of STAM), a de-ubiquitinating enzyme that enhances TGF-beta signaling and epidermal growth factor receptor (EGFR) endosomal recycling. It also acts directly on Smad4 to enhance Smad4 function, and plays a role in prolonged TGF-beta signaling. RNF11 also functions as a critical component of the A20 ubiquitin-editing protein complex that negatively regulates tumor necrosis factor (TNF)-mediated nuclear factor (NF)-kappaB activation. It interacts with Smad anchor for receptor activation (SARA) and the endosomal sorting complex required for transport (ESCRT)-0 complex, thus participating in the regulation of lysosomal degradation of EGFR. RNF11 acts as a novel GGA cargo actively participating in regulating the ubiquitination of the GGA protein family. RNF11 functions together with TAX1BP1 to target TANK-binding kinase 1 (TBK1)/IkappaB kinase IKKi, and further restricts antiviral signaling and type I interferon (IFN)-beta production. RNF11 contains an N-terminal PPPY motif that binds WW domain-containing proteins such as AIP4/itch, Nedd4 and Smurf1/2 (SMAD-specific E3 ubiquitin-protein ligase 1/2), and a C-terminal C3H2C3-type RING-H2 finger that functions as a scaffold for the coordinated transfer of ubiquitin to substrate proteins together with the E2 enzymes UbcH527 and Ubc13.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 28571958 289 CIICRED-MVNHS-KKLPCGHIFHTTCLRSWFQRQQTCPTC 327
Cdd:cd16468   2 CVICMADfVVGDPiRYLPCMHIYHVDCIDDWLMRSFTCPSC 42

RING finger, HC subclass, found in Equid alphaherpesvirus 1 (Equine herpesvirus 1/EHV-1) regulatory protein and similar proteins; EHV-1 regulatory protein belongs to the Vmw110 (IPC0) protein family. It contains a typical C3HC4-type RING-HC finger and binds zinc stably.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 28571958 287 NICIICREDMVNHSKKLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd23130   1 DVCPICLDDPEDEAITLPCLHQFCYTCILRWLQTSPTCPLCK 42

RING finger, H2 subclass, found in RING finger protein 139 (RNF139) and similar proteins; RNF139, also known as translocation in renal carcinoma on chromosome 8 protein (TRC8), is an endoplasmic reticulum (ER)-resident multi-transmembrane protein that functions as a potent growth suppressor in mammalian cells, inducing G2/M arrest, decreased DNA synthesis and increased apoptosis. It is a tumor suppressor that has been implicated in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control. A mutation in RNF139 has been identified in families with hereditary renal (RCC) and thyroid cancers. RNF139 physically and functionally interacts with von Hippel-Lindau (VHL), which is part of an SCF related E3-ubiquitin ligase complex with "gatekeeper" function in renal carcinoma and is defective in most sporadic clear-cell renal cell carcinomas (ccRCC). It suppresses growth and functions with VHL in a common pathway. RNF139 also suppresses tumorigenesis by targeting heme oxygenase-1 for ubiquitination and degradation. Moreover, RNF139 is a target of Translin (TSN), a posttranscriptional regulator of genes transcribed by the transcription factor CREM-tau in postmeiotic male germ cells, suggesting a role of RNF139 in dysgerminoma. In addition, RNF139 forms an integral part of a novel multi-protein ER complex, containing MHC I, US2, and signal peptide peptidase, which is associated with the ER-associated degradation (ERAD) pathway. It is required for the ubiquitination of MHC class I molecules before dislocation from the ER. As a novel sterol-sensing ER membrane protein, RNF139 hinders sterol regulatory element-binding protein-2 (SREBP-2) processing through interaction with SREBP-2 and SREBP cleavage-activated protein (SCAP), regulating its own turnover rate via its E3 ubiquitin ligase activity. RNF139 shows two regions of similarity with the receptor for sonic hedgehog (SHH), Patched. The first region corresponds to the second extracellular domain of Patched, which is involved in binding SHH. The second region is a putative sterol-sensing domain (SSD). The C-terminal half of RNF139 contains a C3H2C3-type RING-H2 finger with E3-ubiquitin ligase activity in vitro.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 28571958 283 RQSDNICIICREDMVNHSKKLPCGHIFHTTCLRSWFQRQQTCPTC 327
Cdd:cd16683   1 REIDDVCAICYQEFTTSARITPCNHYFHALCLRKWLYIQDTCPMC 45

RING finger, H2 subclass, found in TRAF-interacting protein (TRAIP) and similar proteins; TRAIP, also known as RING finger protein 206 (RNF206) or TRIP, is a ubiquitously expressed nucleolar E3 ubiquitin ligase important for cellular proliferation and differentiation. It is found near mitotic chromosomes and functions as a regulator of the spindle assembly checkpoint. TRAIP interacts with tumor necrosis factor (TNF)-receptor-associated factor (TRAF) proteins and inhibits TNF-alpha-mediated nuclear factor (NF)-kappaB activation. It also interacts with two tumor suppressors CYLD and spleen tyrosine kinase (Syk), and DNA polymerase eta, which facilitates translesional synthesis after DNA damage. TRAIP contains an N-terminal C3H2C2-type RING-H2 finger and an extended coiled-coil domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 28571958 288 ICIICrEDMVNHSKKL---PCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16480   1 YCTIC-SDFFDNSRDVaaiHCGHTFHYDCLLQWFDTSRTCPQCR 43

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 28571958 286 DNICIICREDMVNHSK---KLPCGHIFHTTCLRSWF-QRQQTCPTCR 328
Cdd:cd23121   1 DDCCAICLSDFNSDEKlrqLPKCGHIFHHHCLDRWIrYNKITCPLCR 47

RING finger, H2 subclass, found in RING finger proteins RNF139, RNF145, and similar proteins; RNF139, also known as translocation in renal carcinoma on chromosome 8 protein (TRC8), is an endoplasmic reticulum (ER)-resident multi-transmembrane protein that functions as a potent growth suppressor in mammalian cells, inducing G2/M arrest, decreased DNA synthesis and increased apoptosis. It is a tumor suppressor that has been implicated in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control. A mutation in RNF139 has been identified in families with hereditary renal (RCC) and thyroid cancers. RNF145 is an uncharacterized RING finger protein encoded by the RNF145 gene, which is expressed in T lymphocytes, and its expression is altered in acute myelomonocytic and acute promyelocytic leukemias. Although its biological function remains unclear, RNF145 shows high sequence similarity with RNF139. Both RNF139 and RNF145 contain a C3H2C3-type RING-H2 finger with possible E3-ubiquitin ligase activity.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 28571958 287 NICIICREDMVNhSKKLPCGHIFHTTCLRSWFQRQQTCPTC 327
Cdd:cd16476   1 DVCAICYQEMKE-ARITPCNHFFHGLCLRKWLYVQDTCPLC 40

RING finger, H2 subclass, found in Arabidopsis thaliana protein SUGAR INSENSITIVE 3 (SIS3) and similar proteins; SIS3 is an E3 ubiquitin-protein ligase that acts as a positive regulator of sugar signaling during early seedling development. SIS3 contains a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 28571958 289 CIICREDMVNHSKK--LPCGHIFHTTCLRSWFQRQQTCPTCRLNI 331
Cdd:cd23118   3 CTICLEDFEDGEKLrvLPCQHQFHSECVDQWLRRNPKCPVCRRDA 47

Modified RING-CH finger, H2 subclass (C4HC2H-type), found in the ZNRF family; The ZNRF family includes zinc/RING finger proteins ZNRF1, ZNRF2, and similar proteins. It has been characterized by containing a unique combination of zinc finger-RING finger motifs in the C-terminal region, which is evolutionarily conserved in a wide range of species, including Caenorhabditis elegans and Drosophila. ZNRF proteins function as E3 ubiquitin ligases and are highly expressed in central nervous system (CNS) and peripheral nervous system (PNS) neurons, particularly during development and in adulthood. ZNRF1 and ZNRF2 are differentially localized within the synaptic region. ZNRF1 is associated with synaptic vesicle membranes, whereas ZNRF2 is present in presynaptic plasma membranes. They are N-myrisotoylated and also located in the endosome-lysosome compartment in fibroblasts. ZNRF proteins may play a role in the establishment and maintenance of neuronal transmission and plasticity via their ubiquitin ligase activity, as well as in regulating Ca2+-dependent exocytosis. The RING fingers found in ZNRF proteins are modified as C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of the RING-H2 finger.

                        10        20        30
                ....*....|....*....|....*....|....*....
gi 28571958 289 CIICREDMVNHSK--KLPCGHIFHTTCLRSWFQRQQTCP 325
Cdd:cd16489   2 CVICLEELEAGDTiaRLPCLCIYHKKCIDDWFEVNRSCP 40

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 28571958 288 ICIICREDMvNHSKKLPCGHIFHTTCLRSWF--QRQQTCPTCRLNILRTP 335
Cdd:cd16568   6 ECIICHEYL-YEPMVTTCGHTYCYTCLNTWFksNRSLSCPDCRTKITTQP 54

RING finger, H2 subclass, found in RING finger protein 130 (RNF130) and similar proteins; RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL). It is a transmembrane E3 ubiquitin-protein ligase expressed in leukocytes. It has a self-ubiquitination property, and controls the development of T cell clonal anergy by ubiquitination. RNF130 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

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                ....*....|....*....|....*....|....*....|....*....|
gi 28571958 289 CIICRE-----DMVnhsKKLPCGHIFHTTCLRSWFQRQQTCPTCRLNILR 333
Cdd:cd16803   3 CAVCIEgykqnDVV---RILPCKHVFHKSCVDPWLNEHCTCPMCKLNILK 49

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 28571958 287 NICIICREDM-VNHSKKL-------PCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd23117   5 VDCVICMSDIeLPSTNSVrrdymvtPCNHIFHTNCLERWMDIKLECPTCR 54

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 28571958 286 DNICIICREDMVNHSKK----LPCGHIFHTTCLRSWFQRQQ-TCPTCR 328
Cdd:cd16450   2 GNTCPICFEPWTSSGEHrlvsLKCGHLFGYSCIEKWLKGKGkKCPQCN 49

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6 and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. Moreover, RNF6 regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 also binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. RNF6 also acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF6 contains an N-terminal coiled-coil domain, a Lys-X-X-Leu/Ile-X-X-Leu/Ile (KIL) motif, and a C-terminal C3H2C3-type RING-H2 finger which is responsible for its ubiquitin ligase activity. The KIL motif is present in a subset of RING-H2 proteins from organisms as evolutionarily diverse as human, mouse, chicken, Drosophila, Caenorhabditis elegans, and Arabidopsis thaliana.

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                ....*....|....*....|....*....|....*....|....*....
gi 28571958 288 ICIICREDMV--NHSKKLPCGHIFHTTCLRSWFQRQQTCPTCRLNILRT 334
Cdd:cd16673   2 TCSVCINEYAtgNKLRRLPCAHEFHIHCIDRWLSENSTCPICRQPVLGS 50

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6, RNF12, and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. RNF6 also regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. It acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF12, also known as LIM domain-interacting RING finger protein, or RING finger LIM domain-binding protein (R-LIM), is an E3 ubiquitin-protein ligase encoded by gene RLIM that is crucial for normal embryonic development in some species and for normal X inactivation in mice. It thus functions as a major sex-specific epigenetic regulator of female mouse nurturing tissues. RNF12 is widely expressed during embryogenesis, and mainly localizes to the cell nucleus, where it regulates the levels of many proteins, including CLIM, LMO, HDAC2, TRF1, SMAD7, and REX1, by proteasomal degradation. Both RNF6 and RNF12 contain a well conserved C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 28571958 288 ICIICREDMV--NHSKKLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16467   1 ECTICLGEYEtgEKLRRLPCSHEFHSECVDRWLKENSSCPICR 43

RING finger, H2 subclass, found in RING finger proteins RNF121, RNF175 and similar proteins; This subfamily includes RNF121, RNF175 and similar proteins. RNF121 is an E3-ubiquitin ligase present in the endoplasmic reticulum (ER) and cis-Golgi compartments. It is a novel regulator of apoptosis. It also facilitates the degradation and membrane localization of voltage-gated sodium (NaV) channels, and thus plays a role in the quality control of NaV channels during their synthesis and subsequent transport to the membrane. Moreover, RNF121 acts as a broad regulator of nuclear factor kappaB (NF-kappaB) signaling since its silencing also dampens NF-kappaB activation following stimulation of toll-like receptors (TLRs), nod-like receptors (NLRs), RIG-I-like Receptors (RLRs) or after DNA damage. RNF121 contains five conserved transmembrane (TM) domains and a C3H2C2-type RING-H2 finger. RNF175 is an uncharacterized RING finger protein that shows high sequence similarity with RNF121. This family also includes Arabidopsis RING finger E3 ligase RHA2A, RHA2B, and their homologs. RHA2A is a positive regulator of abscisic acid (ABA) signaling during seed germination and early seedling development. RHA2B may play a role in the ubiquitin-dependent proteolysis pathway that respond to proteasome inhibition. All subfamily members contain a C3H2C3-type RING-H2 finger, which is responsible for E3-ubiquitin ligase activity.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 28571958 287 NICIICREDMVNHS---------KKLPCGHIFHTTCLRSW--FQRQQTCPTCR 328
Cdd:cd16475   1 NVCAVCGQKLDVDDneegiiektYKLSCNHVFHEFCIRGWciVGKKQTCPYCK 53

RING finger, H2 subclass, found in RING finger protein 44 (RNF44) and similar proteins; RNF44 is an uncharacterized RING finger protein that shows high sequence similarity with RNF38, which is a nuclear E3 ubiquitin protein ligase that plays a role in regulating p53. RNF44 contains a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), and a C3H2C2-type RING-H2 finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 28571958 281 ELRQSDN-ICIICREDMVNHS--KKLPCGHIFHTTCLRSWFQRQQTCPTCRLNILRTP 335
Cdd:cd16680   1 ENHQSEQtLCVVCFSDFESRQllRVLPCNHEFHTKCVDKWLKTNRTCPICRADASEVH 58

RING finger, H2 subclass, found in BRCA1-associated protein (BRAP2) and similar proteins; BRAP2, also known as impedes mitogenic signal propagation (IMP), RING finger protein 52, or renal carcinoma antigen NY-REN-63, is a novel cytoplasmic protein interacting with the two functional nuclear localization signal (NLS) motifs of BRCA1, a nuclear protein linked to breast cancer. It also binds to the SV40 large T antigen NLS motif and the bipartite NLS motif found in mitosin. BRAP2 serves as a cytoplasmic retention protein and plays a role in the regulation of nuclear protein transport. It contains an N-terminal RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by a C3H2C3-type RING-H2 finger and a UBP-type zinc finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 28571958 289 CIICREDMVNHSKKL---PCGHIFHTTCLRSWFQRqqTCPTCR 328
Cdd:cd16457   3 CPVCLERMDESVSGIltiLCNHSFHCSCLSKWGDS--SCPVCR 43

RING finger, H2 subclass, found in Saccharomyces cerevisiae alcohol-sensitive RING finger protein 1 (ASR1) and similar proteins; ASR1 is required for tolerance to alcohol. It signals alcohol stress to the nucleus. ASR1 contains a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 28571958 289 CIICREDM-VNHSKKLPCGHIFHTTCLRSWFQR--QQTCPTCR 328
Cdd:cd23120   4 CPICLEEMnSGTGYLADCGHEFHLTCIREWHNKsgNLDCPICR 46

RING finger, H2 subclass, found in rice E3 ubiquitin-protein ligase EL5 and similar proteins; EL5, also known as protein ELICITOR 5, is an E3 ubiquitin-protein ligase containing an N-terminal transmembrane domain and a C3H2C3-type RING-H2 finger that is a binding site for ubiquitin-conjugating enzyme (E2). It can be rapidly induced by N-acetylchitooligosaccharide elicitor. EL5 catalyzes polyubiquitination via the Lys48 residue of ubiquitin, and thus plays a crucial role as a membrane-anchored E3 in the maintenance of cell viability after the initiation of root primordial formation in rice. It also acts as an anti-cell death enzyme that might be responsible for mediating the degradation of cytotoxic proteins produced in root cells after the actions of phytohormones. Moreover, EL5 interacts with UBC5b, a rice ubiquitin carrier protein, through its RING-H2 finger. EL5 is an unstable protein, and its degradation is regulated by the C3H2C3-type RING-H2 finger in a proteasome-independent manner.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 28571958 288 ICIICREDMVNHSK--KLP-CGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16461   1 ECAICLSDYENGEElrRLPeCKHAFHKECIDEWLKSNSTCPLCR 44

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 28571958 277 ATPEELRQSDNICIIC----REDMVnhskkLPCGHIFHTTCLRSWFQRQQTCPTCRLNILRT 334
Cdd:cd16742   4 ATSQQCSEAGDICAICqaefREPLI-----LICQHVFCEECLCLWFDRERTCPLCRSVVVET 60

RING finger, H2 subclass, found in RING finger protein 165 (RNF165) and similar proteins; 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. RNF165 contains two serine rich domains, a nuclear localization signal, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is responsible for the enhancement of BMP-Smad1/5/8 signaling in the spinal cord.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 28571958 280 EELRQSDNICIICREDMVNHS--KKLPCGHIFHTTCLRSWFQRQQTCPTCRLNI 331
Cdd:cd16682   1 GEESDTDEKCTICLSMLEDGEdvRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 54

RING finger, H2 subclass, found in RING finger protein 111 (RNF111) 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 acts as an amplifier of Nodal signals, and enhances the dorsalizing activity of limiting amounts of Xnr1, a Nodal homolog, and requires Nodal signaling for its function. The loss of RNF111 results in early embryonic lethality, with defects attributed to compromised Nodal signaling. RNF111 also regulates tumor metastasis by modulation of the TGF-beta pathway. Its ubiquitination can be modulated by the four and a half LIM-only protein 2 (FHL2) that activates TGF-beta signal transduction. Furthermore, RNF111 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. In addition, RNF111 has been identified as a small ubiquitin-like modifier (SUMO)-binding protein with clustered SUMO-interacting motifs (SIMs) that together form a SUMO-binding domain (SBD). 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). The N-terminal half of RNF111 harbors three SIMs. Its C-terminal half show high sequence similarity with RING finger protein 165 (RNF165), where it contains two serine rich domains, two nuclear localization signals, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is required for polyubiqutination and proteasome-dependent degradation of phosphorylated forms of Smad2/3 and three major negative regulators of TGF-beta signaling, Smad7, SnoN and c-Ski.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 28571958 276 DATPEELRQSDNICIICREDMVNhSKKLPCGHIFHTTCLRSWFQRQQTCPTCRLNI 331
Cdd:cd16681   3 EGTEEDTEEKCTICLSILEEGED-VRRLPCMHLFHQVCVDQWLITNKKCPICRVDI 57

RING finger, H2 subclass, found in RING finger protein 150 (RNF150) and similar proteins; RNF150 is a RING finger protein and its polymorphisms may be associated with chronic obstructive pulmonary disease (COPD) risk in the Chinese population. Further studies with larger numbers of participants worldwide are needed for validation of the relationships between RNF150 genetic variants and the pathogenesis of COPD. RNF150 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 28571958 286 DNiCIICRE-----DMVnhsKKLPCGHIFHTTCLRSWFQRQQTCPTCRLNILR 333
Cdd:cd16805   7 DN-CAVCIEgykpnDVV---RILPCRHLFHKSCVDPWLLDHRTCPMCKMNILK 55

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
                ....*....|....*....|....*....|....*....|..
gi 28571958 289 CIICREDMVNHS--KKLPCGHIFHTTCLRSWFQ-RQQTCPTC 327
Cdd:cd00162   1 CPICREEMNDRRpvVLLSCGHTFSRSAIARWLEgSKQKCPFC 42

RING finger, H2 subclass, found in RING finger proteins RNF38, RNF44, and similar proteins; This subfamily includes RING finger proteins RNF38, RNF44, and similar proteins. RNF38 is a nuclear E3 ubiquitin protein ligase that plays a role in regulating p53. RNF44 is an uncharacterized RING finger protein that shows high sequence similarity to RNF38. Both RNF38 and RNF44 contain a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), and a C3H2C3-type RING-H2 finger. In addition, RNF38 harbors two potential nuclear localization signals.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 28571958 289 CIICREDMVN--HSKKLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd16472   5 CVVCMCDYEKrqLLRVLPCSHEFHAKCIDKWLKTNRTCPICR 46

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 28571958 288 ICIICREDMVNHSKKLPCGHIFHTTCLRSWFQRQ-QTCPTCRLNILR 333
Cdd:cd16503   4 TCSICQDLLHDCVSLQPCMHNFCAACYSDWMERSnTECPTCRATVQR 50

RING finger, H2 subclass, found in p53-induced RING-H2 protein (Pirh2) and similar proteins; Pirh2, also known as RING finger and CHY zinc finger domain-containing protein 1 (Rchy1), androgen receptor N-terminal-interacting protein, CH-rich-interacting match with PLAG1, RING finger protein 199 (RNF199), or zinc finger protein 363 (ZNF363), is a p53 inducible E3 ubiquitin-protein ligase that functions as a negative regulator of p53. It preferably ubiquitylates the tetrameric form of p53 in vitro and in vivo, suggesting a role of Pirh2 in downregulating the transcriptionally active form of p53 in the cell. Moreover, Pirh2 inhibits the transcriptional activity of p73, a homolog of the tumor suppressor p53, by promoting its ubiquitination. It also monoubiquitinates DNA polymerase eta (PolH) to suppress translesion DNA synthesis. Furthermore, Pirh2 functions as a negative regulator of the cyclin-dependent kinase inhibitor p27(Kip1) function by promoting ubiquitin-dependent proteasomal degradation. Pirh2 enhances androgen receptor (AR) signaling through inhibition of histone deacetylase 1 (HDAC1) and is overexpressed in prostate cancer. It interacts with TIP60 and this association may regulate Pirh2 stability. In addition, the oncoprotein pleomorphic adenoma gene like 2 (PLAGL2) can bind to the Pirh2 dimer and therefore control the stability of Pirh2. Pirh2 contains a total of nine zinc-binding sites with six located at the N-terminal region, two in the C3H2C3-type RING-H2 domain, and one in the C-terminal region. Nine zinc binding sites comprise three different zinc coordination schemes, including RING type cross-brace zinc coordination, C4 zinc finger, and a novel left-handed beta-spiral zinc-binding motif formed by three recurrent CCHC sequence motifs. This subfamily also includes Drosophila melanogaster Deltex, a ubiquitously expressed cytoplasmic ubiquitin E3 ligase that mediates Notch activation in Drosophila. It selectively suppresses T-cell activation through degradation of a key signaling molecule, MAP kinase kinase kinase 1 (MEKK1). It also inhibits Jun-mediated transcription at the stage of Ras-dependent Jun N-terminal protein kinase (JNK) activation. Deltex contains N-terminal two Notch-binding WWE domains that physically interact with the Notch ankyrin domains, a proline-rich motif that shares homology with SH3-binding domains, and a RING finger at the C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 28571958 289 CIICREDMVNH---SKKLPCGHIFHTTCLRSwFQRQQ--TCPTCR 328
Cdd:cd16464   2 CPVCLEDLFTSrepVHVLPCGHLMHSTCFEE-YLKSGnyRCPLCS 45

RING finger, H2 subclass, found in RING finger protein 43 (RNF43) and similar proteins; RNF43 is a transmembrane E3 ubiquitin-protein ligase that plays an important role in frizzled (FZD)-dependent regulation of the Wnt/beta-catenin pathway. It functions as a tumor suppressor that inhibits Wnt/beta-catenin signaling by ubiquitinating FZD receptor and targeting it to the lysosomal pathway for degradation. miR-550a-5p directly targeted the 3'-UTR of gene RNF43 and regulated its expression. Moreover, RNF43 interacts with NEDD-4-like ubiquitin-protein ligase-1 (NEDL1) and regulates p53-mediated transcription. It may also be involved in cell growth control through the interaction with HAP95, a chromatin-associated protein interfacing the nuclear envelope. Mutations of RNF43 have been identified in various tumors, including colorectal cancer (CRC), endometrial cancer, mucinous ovarian tumors, gastric adenocarcinoma, pancreatic ductal adenocarcinoma, liver fluke-associated cholangiocarcinoma, hepatocellular carcinoma, and glioma. RNF43 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C3H2C3-type RING-H2 finger followed by a long C-terminal region.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 28571958 285 SDNICIICREDMVNHS--KKLPCGHIFHTTCLRSWFQRQQTCPTCRLNIL 332
Cdd:cd16798   2 SAPVCAICLEEFSEGQelRIISCSHEFHRECVDPWLHQHRTCPLCMFNII 51

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 28571958 288 ICIICREDMVNhSKKLPCGHIFHTTCLRSWFQ-RQQTCPTC 327
Cdd:cd16449   2 ECPICLERLKD-PVLLPCGHVFCRECIRRLLEsGSIKCPIC 41

RING finger, H2 subclass, found in RING finger protein 167 (RNF167) and similar proteins; RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) ubiquitination. It ubiquitinates AMPA-type glutamate receptor subunit GluA2 and regulates its surface expression, and thus acts as a selective regulator of AMPAR-mediated neurotransmission. It acts as an endosomal membrane protein which ubiquitylates vesicle-associated membrane protein 3 (VAMP3) and regulates endosomal trafficking. Moreover, RNF167 plays a role in the regulation of TSSC5 (tumor-suppressing subchromosomal transferable fragment cDNA, also known as ORCTL2/IMPT1/BWR1A/SLC22A1L), which can function in concert with the ubiquitin-conjugating enzyme UbcH6. RNF167 is widely conserved in metazoans and contains an N-terminal signal peptide, a protease-associated (PA) domain, two transmembrane domains (TM1 and TM2), and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 28571958 287 NICIICREDMVNHSK--KLPCGHIFHTTCLRSWFQR-QQTCPTCR 328
Cdd:cd16797   1 DVCAICLDEYEEGDKlrVLPCSHAYHSKCVDPWLTQtKKTCPVCK 45

RING finger, H2 subclass, found in RING finger protein 24 (RNF24) 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. RNF24 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 28571958 288 ICIICREDMVNHSKK--LPCGHIFHTTCLRSWFQRQQTCPTCRLNILR 333
Cdd:cd16675   2 ICAVCLEEFKPKDELgiCPCKHAFHRKCLIKWLEVRKVCPLCNMPVLQ 49

RING-CH finger, H2 subclass (C4HC3-type), found in E3 ubiquitin-protein ligase listerin and similar proteins; Listerin, also known as RING finger protein 160 or zinc finger protein 294, is the mammalian homolog of yeast Ltn1. It is widely expressed in all tissues, but motor and sensory neurons and neuronal processes in the brainstem and spinal cord are primarily affected in the mutant. Listerin is required for embryonic development and plays an important role in neurodegeneration. It also functions as a critical E3 ligase involving quality control of nonstop proteins. It mediates ubiquitylation of aberrant proteins that become stalled on ribosomes during translation. Ltn1 works with several cofactors to form a large ribosomal subunit-associated quality control complex (RQC), which mediates the ubiquitylation and extraction of ribosome-stalled nascent polypeptide chains for proteasomal degradation. It appears to first associate with nascent chain-stalled 60S subunits together with two proteins of unknown function, Tae2 and Rqc1. Listerin contains a long stretch of HEAT (Huntingtin, Elongation factor 3, PR65/A subunit of protein phosphatase 2A, and TOR) or ARM (Armadillo) repeats in the N terminus and middle region, and a catalytic RING-CH finger, also known as vRING or RINGv, with an unusual arrangement of zinc-coordinating residues in the C-terminus . Its cysteines and histidines are arranged in the sequence as C4HC3-type, rather than the C3H2C3-type in canonical RING-H2 finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 28571958 289 CIICRE--DMVNHSkkLP------CGHIFHTTCLRSWFQ--RQQTCPTCR 328
Cdd:cd16491   3 CPICYSviHGSNHS--LPklkcktCKNKFHSACLYKWFRssNKSTCPLCR 50

RING finger, H2 subclass, found in zinc/RING finger protein 3 (ZNRF3) and similar proteins; ZNRF3, also known as RING finger protein 203 (RNF203), is a homolog of Ring finger protein 43 (RNF43). It is a transmembrane E3 ubiquitin-protein ligase that is associated with the Wnt receptor complex, and negatively regulates Wnt signaling by promoting the turnover of frizzled and lipoprotein receptor-related protein LRP6 in an R-spondin-sensitive manner. It inhibits gastric cancer cell growth and promotes cell apoptosis by affecting the Wnt/beta-catenin/TCF signaling pathway. ZNRF3 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C3H2C3-type RING-H2 finger followed by a long C-terminal region.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 28571958 289 CIICREDMVNHS--KKLPCGHIFHTTCLRSWFQRQQTCPTCRLN 330
Cdd:cd16799   2 CAICLEKYIDGEelRVIPCTHRFHKKCVDPWLLQHHTCPHCRHN 45

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 28571958 289 CIICREDMvNHSKKLPCGHIFHTTCLRSWFQRQQTCPTCR 328
Cdd:cd23135   6 CSICFSEI-RSGAILKCGHFFCLSCIASWLREKSTCPLCK 44

Modified RING finger, H2 subclass (C3H3C2-type), found in WD repeat-containing protein mio and its homologs; This subfamily contains Mio, WDR24, WDR59, and their counterparts Sea4, Sea2, and Sea3 from yeast, respectively. Mio/Sea4, Sea2/WDR24, and Sea3/WDR59 are components of the GATOR2 complex, which also includes another two subunits, Seh1and Sec13. GATOR2 and GATOR1, which is composed of three subunits, DEPDC5, Nprl2, and Nprl3, form the Rag-interacting complex GATOR (GAP Activity Towards Rags). Inhibition of GATOR1 subunits makes mTORC1 signaling resistant to amino acid deprivation. In contrast, inhibition of GATOR2 subunits suppresses mTORC1 signaling and GATOR2 negatively regulates DEPDC5. All subfamily members contain an N-terminal WD40 domain and a C-terminal RING-H2 finger with an unusual arrangement of zinc-coordinating residues. The cysteines and histidines in the RING-H2 finger are arranged as a modified C3H3C2-type, rather than the canonical C3H2C3-type.

                        10        20
                ....*....|....*....|....
gi 28571958 303 LPCGHIFHTTCLRSWFQRQQTCPT 326
Cdd:cd16488  17 LNCGHGGHAECIREWFEDHTECPT 40