Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 256818810  295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:pfam13639   3 CPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 256818810 288 ESDTDEKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWL-AMSKKCPICRVDI 339
Cdd:COG5540  319 EADKGVECAICMSNFIKNDRLRVLPCDHRFHVGCVDKWLlGYSNKCPVCRTAI 371

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 256818810 284 DEGEESDTDEKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDIETQL 343
Cdd:cd16681    2 EEGTEEDTEEKCTICLSILEEGEDVRRLPCMHLFHQVCVDQWLITNKKCPICRVDIEAQL 61

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 256818810 293 EKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd23118    1 KTCTICLEDFEDGEKLRVLPCQHQFHSECVDQWLRRNPKCPVCRRDA 47

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 256818810  295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:pfam13639   3 CPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

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 256818810 294 KCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16467    1 ECTICLGEYETGEKLRRLPCSHEFHSECVDRWLKENSSCPICR 43

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 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWL-AMSKKCPICR 336
Cdd:cd16448    1 CVICLEEFEEGDVVRLLPCGHVFHLACILRWLeSGNNTCPLCR 43

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.

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                 ....*....|....*....|....*....|....*....|....*
gi 256818810 293 EKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKK-CPICR 336
Cdd:cd16797    1 DVCAICLDEYEEGDKLRVLPCSHAYHSKCVDPWLTQTKKtCPVCK 45

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 256818810 292 DEKCTICLSMLEDGEDVRRLP-CMHLFHQLCVDQWLAMSK-KCPICRVD 338
Cdd:cd23121    1 DDCCAICLSDFNSDEKLRQLPkCGHIFHHHCLDRWIRYNKiTCPLCRAD 49

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 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPIC 335
Cdd:cd16468    2 CVICMADFVVGDPIRYLPCMHIYHVDCIDDWLMRSFTCPSC 42

RING finger, H2 subclass, found in RING finger protein 181 (RNF181) and similar proteins; RNF181, also known as HSPC238, is a platelet E3 ubiquitin-protein ligase containing a C3H2C3-type RING-H2 finger. It interacts with the KVGFFKR motif of platelet integrin alpha(IIb)beta3, suggesting a role for RNF181-mediated ubiquitination in integrin and platelet signaling. It also suppresses the tumorigenesis of hepatocellular carcinoma (HCC) through the inhibition of extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling in the liver.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 256818810 294 KCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16669    1 KCPICLLEFEEGETVKQLPCKHSFHSDCILPWLGKTNSCPLCR 43

RING finger, H2 subclass, found in RING finger proteins, RNF130, RNF149, RNF150 and similar proteins; This subfamily includes RING finger proteins, RNF130, RNF149 and RNF150, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by 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. RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128. 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. RNF133 is a testis-specific endoplasmic reticulum-associated E3 ubiquitin ligase that may play a role in sperm maturation through an ER-associated degradation (ERAD) pathway. RNF149, also known as DNA polymerase-transactivated protein 2, is an E3 ubiquitin-protein ligase that induces the ubiquitination of wild-type v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) and promotes its proteasome-dependent degradation. RNF150 polymorphisms may be associated with chronic obstructive pulmonary disease (COPD) risk in the Chinese population. This subfamily also includes Drosophila melanogaster protein goliath (d-goliath), also known as protein g1, which is one of the founding members of the group. It was originally identified as a transcription factor involved in the embryo mesoderm formation.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16668    2 CAVCIEPYKPSDVIRILPCKHIFHKSCVDPWLLEHRTCPMCKLDI 46

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
                 ....*....|....*....|....*....|....*....|....
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVD 338
Cdd:cd16680   10 CVVCFSDFESRQLLRVLPCNHEFHTKCVDKWLKTNRTCPICRAD 53

RING finger, H2 subclass, found in Arabidopsis thaliana MED25-binding RING-H2 protein (MBR) and similar proteins; This subfamily includes MBR1 and MBR2 (also called HAL3-interacting protein 1 or AtHIP1). They are E3 ubiquitin-protein ligases that function as regulators of MED25 stability by targeting MED25 for degradation in a RING-H2-dependent manner. Proteasome-dependent degradation of MED25 seems to activate its function as a positive regulator of FLOWERING LOCUS T (FT) and is important to induce the expression of FT, and consequently to promote flowering. MBR2 may also function downstream of HAL3 and be required for HAL3-regulated plant growth. Activation of MBR2 by HAL3 may lead to the degradation of cell cycle suppressors, resulting in enhancement of cell division and plant growth. Both MBR1 and MBR2 contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 256818810 291 TDEKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd23113    1 SDEKCCICQEEYEEGDELGTIECGHEYHSDCIKQWLVQKNLCPICK 46

RING finger, H2 subclass, found in RING finger proteins RNF43, ZNRF3, and similar proteins; RNF43 and ZNRF3 (also known as RNF203) are transmembrane E3 ubiquitin-protein ligases that belong to the PA-TM-RING ubiquitin ligase family, characterized by containing 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. Both RNF43 and RNF203 function as tumor suppressors involved in the regulation of Wnt/beta-catenin signaling. They negatively regulate Wnt signaling by interacting with complexes of frizzled (FZD) receptors and low-density lipoprotein receptor-related protein (LRP) 5/6, which leads to ubiquitination of FZD and endocytosis of the Wnt receptor. Dishevelled (DVL), a positive Wnt regulator, is required for ZNRF3/RNF43-mediated ubiquitination and degradation of FZD. They also associate with R-spondin 1 (RSPO1). This interaction may block FZD ubiquitination and enhances Wnt signaling.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVD 338
Cdd:cd16666    2 CAICLEEYEEGQELRVLPCQHEFHRKCVDPWLLQNHTCPLCLFN 45

RING finger, H2 subclass, found in RING finger protein 149 (RNF149) and similar proteins; RNF149, also known as DNA polymerase-transactivated protein 2, is an E3 ubiquitin-protein ligase that interacts with wild-type v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), a RING domain-containing E3 ubiquitin ligase involved in control of gene transcription, translation, cytoskeletal organization, cell adhesion, and epithelial development. RNF149 induces the ubiquitination of wild-type BRAF and promotes its proteasome-dependent degradation. Mutated RNF149 has been found in some human breast, ovarian, and colorectal cancers. RNF149 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
                 ....*....|....*....|....*....|....*....|....*
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16804    2 CAVCIENYKSKDVVRILPCKHVFHRICIDPWLLEHRTCPMCKLDV 46

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 256818810 288 ESDTDeKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16805    3 ESDFD-NCAVCIEGYKPNDVVRILPCRHLFHKSCVDPWLLDHRTCPMCKMNI 53

RING finger, H2 subclass, found in RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), and similar proteins; This subfamily includes RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), Zinc/RING finger protein 4 (ZNRF4), and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane domain (TM), and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that functions in the regulation of cancer development, muscle cell growth, and neuronal development. Its expression is developmentally regulated during myogenesis and is upregulated in various tumors. RNF13 negatively regulates cell proliferation through its E3 ligase activity. RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in the ubiquitination of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). 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. ZNRF4, also known as RING finger protein 204 (RNF204), or Nixin, is an endoplasmic reticulum (ER) membrane-anchored ubiquitin ligase that physically interacts with the ER-localized chaperone calnexin in a glycosylation-independent manner, inducing calnexin ubiquitination, and p97-dependent degradation. The murine protein sperizin (spermatid-specific ring zinc finger) is a homolog of human ZNRF4. It is specifically expressed in Haploid germ cells and is involved in spermatogenesis.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKK-CPICR 336
Cdd:cd16665    3 CAICLDDYEEGDKLRILPCSHAYHCKCIDPWLTKNKRtCPVCK 45

RING finger, H2 subclass, found in RING finger protein 128 (RNF128) and similar proteins; This subfamily includes RING finger proteins RNF128, RNF133, RNF148, and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL), is a type 1 transmembrane E3 ubiquitin-protein ligase that is a critical regulator of adaptive immunity and development. It inhibits cytokine gene transcription, is expressed in anergic CD4+ T cells, and has been implicated in primary T cell activation, survival, and differentiation, as well as in T cell anergy and oral tolerance. It induces T cell anergy through the ubiquitination activity of its cytosolic RING finger. It regulates expression of the costimulatory molecule CD40L on CD4 T cells, and ubiquitinates the costimulatory molecule CD40 ligand (CD40L) during the induction of T cell anergy. Moreover, RNF128 interacts with the luminal/extracellular portion of both CD151 and the related tetraspanin CD81 via its PA domain, which promoted ubiquitination of cytosolic lysine residues. It also down-modulates the expression of CD83 (previously described as a cell surface marker for mature dendritic cells) on CD4 T cells. Furthermore, Rho guanine dissociation inhibitor (RhoGDI) has been identified as a potential substrate of RNF128, suggesting a role for Rho effector molecules in T cell anergy. In addition, RNF128 plays a role in environmental stress responses. It promotes environmental salinity tolerance in euryhaline tilapia. RNF133 is a testis-specific endoplasmic reticulum-associated E3 ubiquitin ligase that is mainly present in the cytoplasm of elongated spermatids. It may play a role in sperm maturation through an ER-associated degradation (ERAD) pathway. RNF148 is a testis-specific E3 ubiquitin ligase that is abundantly expressed in testes and slightly expressed in pancreas. Its expression is regulated by histone deacetylases.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 256818810 293 EKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16802    1 DSCAVCIEPYKPNDVVRILTCNHLFHKNCIDPWLLEHRTCPMCKCDI 47

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
                 ....*....|....*....|....*....|....*....|....*
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16798    6 CAICLEEFSEGQELRIISCSHEFHRECVDPWLHQHRTCPLCMFNI 50

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 256818810   295 CTICLSmlEDGEDVRRLPCMHLFHQLCVDQWLAMS-KKCPIC 335
Cdd:smart00184   1 CPICLE--EYLKDPVILPCGHTFCRSCIRKWLESGnNTCPIC 40

RING finger, H2 subclass, found in RING finger protein 38 (RNF38) and similar proteins; RNF38 is a nuclear E3 ubiquitin protein ligase that is widely expressed throughout the human body, and is especially highly expressed in the heart, brain, placenta and the testis. It recognizes p53 as a substrate for ubiquitination, and thus plays a role in regulating p53. The overexpression of RNF38 increases p53 ubiquitination and alters p53 localization. It is also capable of autoubiquitination. RNF38 expression is negatively regulated by the serotonergic system. Induction of RNF38 may be involved in the anxiety-like behavior or non-cell autonomy in Oryzias latipes by the decline of serotonin (5-HT) levels. RNF38 contains a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), a C3H2C3-type RING-H2 finger, as well as two potential nuclear localization signals.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVD 338
Cdd:cd16679   23 CVVCMCDFESRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRAD 66

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 256818810 295 CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16480    2 CTICSDFFDNSRDVAAIHCGHTFHYDCLLQWFDTSRTCPQCR 43

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 256818810  294 KCTICLSMLEDGEDVRrlPCMHLFHQLCVDQWLAMSKKCPIC 335
Cdd:pfam13923   1 MCPICMDMLKDPSTTT--PCGHVFCQDCILRALRAGNECPLC 40

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 256818810 295 CTICLSMLEdgEDVRrLPCMHLFHQLCVDQWLAMSKKCPICRVDIETQ 342
Cdd:cd16535    4 CSICSELFI--EAVT-LNCSHSFCSYCITEWMKRKKECPICRKPITSK 48

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 256818810 288 ESDTDEKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWL-AMSKKCPICRVDI 339
Cdd:COG5540  319 EADKGVECAICMSNFIKNDRLRVLPCDHRFHVGCVDKWLlGYSNKCPVCRTAI 371

RING-like zinc finger;

                          10        20
                  ....*....|....*....|....*...
gi 256818810  295 CTICLSMLEDGEDVRRLPCMHLFHQLCV 322
Cdd:pfam17123   2 CSICLDEFKPGQALFVLPCSHVFHYKCI 29

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 256818810 292 DEKCTICLSMLEDGEdvRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16479    1 DNTCIICREEMTVGA--KKLPCGHIFHLSCLRSWLQRQQTCPTCR 43

RING finger, H2 subclass, found in DAZ (deleted in azoospermia)-interacting protein 3 (DZIP3) and similar proteins; DZIP3, also known as RNA-binding ubiquitin ligase of 138 kDa (RUL138) or 2A-HUB protein, is an RNA-binding E3 ubiquitin-protein ligase that interacts with coactivator-associated arginine methyltransferase 1 (CARM1) and acts as a transcriptional coactivator of estrogen receptor (ER) alpha. It is also a histone H2A ubiquitin ligase that catalyzes monoubiquitination of H2A at lysine 119, functioning as a combinatorial component of the repression machinery required for repressing a specific chemokine gene expression program, critically modulating migratory responses to Toll-like receptors (TLR) activation. DZIP3 contains a C3H2C3-type RING-H2 finger at the C-terminus.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 256818810 293 EKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16460    1 TPCVICHEAFSDGDRLLVLPCAHKFHTQCIGPWLDGQQTCPTCR 44

RING finger, H2 subclass, found in autocrine motility factor receptor (AMFR) and similar proteins; AMFR, also known as AMF receptor, or RING finger protein 45, or ER-protein gp78, is an internalizing cell surface glycoprotein localized in both plasma membrane caveolae and the endoplasmic reticulum (ER). It is involved in the regulation of cellular adhesion, proliferation, motility and apoptosis, as well as in the process of learning and memory. AMFR also functions as a RING finger-dependent ubiquitin protein ligase (E3) implicated in the degradation from the ER. AMFR contains an N-terminal RING-H2 finger and a C-terminal ubiquitin-associated (UBA)-like CUE domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 256818810 293 EKCTICLSMLEDGedvRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16455    1 DDCAICWESMQSA---RKLPCGHLFHNSCLRSWLEQDTSCPTCR 41

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        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 256818810 289 SDTDEKCTICLSmlEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPIC--RVDIE 340
Cdd:cd16683    1 REIDDVCAICYQ--EFTTSARITPCNHYFHALCLRKWLYIQDTCPMChqKVYIE 52

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 256818810 292 DEKCTICLSMLEDGEDVR--RLPCMHLFHQLCVDQWLAMS-KKCPICR 336
Cdd:cd16450    2 GNTCPICFEPWTSSGEHRlvSLKCGHLFGYSCIEKWLKGKgKKCPQCN 49

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 256818810 292 DEKCTICLsmlEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16561    2 EQECSICL---EDLNDPVKLPCDHVFCEECIRQWLPGQMSCPLCRTEL 46

HRD ubiquitin ligase complex, ER membrane component [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 256818810 285 EGEESDTDEKCTICL-SMLEDGEDV---------RRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:COG5243  280 EEQLTNSDRTCTICMdEMFHPDHEPlprgldmtpKRLPCGHILHLHCLKNWLERQQTCPICR 341

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 256818810 293 EKCTICLSMLeDGEDvRRLP------CMHLFHQLCVDQWLAMSKK--CPICR 336
Cdd:cd16491    1 EECPICYSVI-HGSN-HSLPklkcktCKNKFHSACLYKWFRSSNKstCPLCR 50

RING finger, H2 subclass, found in vacuolar protein sorting-associated protein 11 homolog (Vps11) and similar proteins; Vps11, also known as RING finger protein 108 (RNF108), is a soluble protein involved in regulation of glycolipid degradation and retrograde toxin transport. It is highly expressed in heart and pancreas. Vps11 associates with Vps16, Vps18, and Vps33 to form a Class C Vps core complex that is required for soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE)-mediated membrane fusion at the lysosome-like yeast vacuole. The core complex, together with two additional compartment-specific subunits, forms the tethering complexes HOPS (homotypic vacuole fusion and protein sorting) and CORVET (class C core vacuole/endosome transport). CORVET contains the additional Vps3 and Vps8 subunits. It operates at endosomes, controls traffic into late endosomes and interacts with the Rab5/Vps21-GTP form. HOPS contains the additional Vps39 and Vps41 subunits. It operates at the lysosomal vacuole, controls all traffic from late endosomes into the vacuole and interacts with the Rab7/Ypt7-GTP form. Vps11 is a central scaffold protein upon which both HOPS and CORVET assemble. The HOPS and CORVET complexes disassemble in the absence of Vps11, resulting in massive fragmentation of vacuoles. Vps11 contains a clathrin repeat domain and a C-terminal C3H2C3-type RING-H2 finger. This subfamily also includes Vps11 homologs found in fungi, such as Saccharomyces cerevisiae vacuolar membrane protein Pep5p, also known as carboxypeptidase Y-deficient protein 5, vacuolar morphogenesis protein 1, or vacuolar biogenesis protein END1. Pep5p is essential for vacuolar biogenesis. It associates with Pep3p to form a core Pep3p/Pep5p complex that promotes vesicular docking/fusion reactions in conjunction with SNARE proteins at multiple steps in transport routes to the vacuole.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 256818810 294 KCTICLSMLEdgedvrrLP-----CMHLFHQLCVDQWLAMSKKCPICRVD 338
Cdd:cd16688    2 KCSACGSTLD-------LPsvhflCGHSFHQHCLEDYEENDRECPLCAPE 44

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 256818810 290 DTDEKCTICLSMLEDGEDvrrLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd23135    1 KQKLSCSICFSEIRSGAI---LKCGHFFCLSCIASWLREKSTCPLCK 44

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 256818810 295 CTIC-----LSMLEDG--EDVRRLPCMHLFHQLCVDQWLAMSKK--CPICR 336
Cdd:cd16475    3 CAVCgqkldVDDNEEGiiEKTYKLSCNHVFHEFCIRGWCIVGKKqtCPYCK 53

The RING-variant domain is a C4HC3 zinc-finger like motif found in a number of cellular and viral proteins; Some of these proteins have been shown both in vivo and in vitro to have ubiquitin E3 ligase activity. The RING-variant domain is reminiscent of both the RING and the PHD domains and may represent an evolutionary intermediate. To describe this domain the term PHD/LAP domain has been used in the past. Extended description: The RING-variant (RINGv) domain contains a C4HC3 zinc-finger-like motif similar to the PHD domain, while some of the spacing between the Cys/His residues follow a pattern somewhat closer to that found in the RING domain. The RINGv domain, similar to the RING, PHD and LIM domains, is thought to bind two zinc ions co-ordinated by the highly conserved Cys and His residues. RING variant domain: C-x (2) -C-x(10-45)-C-x (1) -C-x (7) -H-x(2)-C-x(11-25)-C-x(2)-C As opposed to a PHD: C-x(1-2) -C-x (7-13)-C-x(2-4)-C-x(4-5)-H-x(2)-C-x(10-21)-C-x(2)-C Classical RING domain: C-x (2) -C-x (9-39)-C-x(1-3)-H-x(2-3)-C-x(2)-C-x(4-48) -C-x(2)-C

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*....
gi 256818810   295 CTICLSMLEDGEDVRRlPC-----MHLFHQLCVDQWLAMS--KKCPICR 336
Cdd:smart00744   2 CRICHDEGDEGDPLVS-PCrckgsLKYVHQECLERWINESgnKTCEICK 49

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 256818810 292 DEKCTICLSMLEDgeDVRRL-PCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16574    1 DSSCPICLDRFEN--EKAFLdGCFHAFCFTCILEWSKVKNECPLCK 44

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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 256818810 286 GEESDTDEKCTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPIC 335
Cdd:cd23122    5 GIQDACEDACSICLESFCEADPATVTSCKHEYHLQCILEWSQRSKECPMC 54

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 256818810 293 EKCTICLSMLEDgedVRRLPCMHLFHQLCVDQWL-AMSKKCPIC 335
Cdd:cd16449    1 LECPICLERLKD---PVLLPCGHVFCRECIRRLLeSGSIKCPIC 41

Modified RING finger, H2 subclass (C3DHC3-type), found in zinc finger protein-like 1 (ZFPL1) and similar proteins; ZFPL1, also known as zinc finger protein MCG4, is a novel mitotic Golgi phosphoprotein required for cis-Golgi integrity and efficient endoplasmic reticulum (ER)-to-Golgi transport via directly interacting with the cis-Golgi matrix protein GM130. ZFPL1 is a widely expressed integral membrane protein with two predicted zinc fingers at its N-terminus. One is a novel type of zinc finger, and the other is a modified RING-H2 finger that lacks the fourth zinc-binding residue of the consensus C3H2C3-type RING-H2 finger. It also contains a bipartite nuclear localization signal (NLS), and a leucine zipper at the C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 256818810 292 DEKCTICLSMLEDGEDVRrLPCMHLFHQLCVDQWLA-MSK-------KCPICRVDI 339
Cdd:cd16487    1 DPNCTLCNTSLANGDVVR-LVCYDLFHWSCLNEYAAqLPAntapagyTCPQCKGPI 55

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 256818810 289 SDTDEKCTICLSMLEDGedvRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16741   11 SEADDICAICQAEFRKP---ILLICQHVFCEECISLWFNREKTCPLCRTVI 58

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 256818810 295 CTICLsmlEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICR 336
Cdd:cd16532    3 CPICQ---DEFKDPVVLRCKHIFCEDCVSEWFERERTCPLCR 41

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 256818810 294 KCTICLsmlEDGEDVRRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 339
Cdd:cd16546    2 ECPICL---QTCIHPVKLPCGHIFCYLCVKGVAWQSKRCALCRQEI 44

RING finger, HC subclass, found in Casitas B-lineage lymphoma (Cbl) proteins; The Cbl adaptor protein family contains a small class of RING-type E3 ubiquitin ligases with oncogenic activity, which is represented by three mammalian members, c-Cbl, Cbl-b and Cbl-c, as well as two invertebrate Cbl-family proteins, D-Cbl in Drosophila and Sli-1 in C. elegans. Cbl proteins function as potent negative regulators of various signaling cascades in a wide range of cell types. They play roles in ubiquitinating activated tyrosine kinases and targeting them for degradation. D-Cbl associates with the Drosophila epidermal growth factor receptor (EGFR) and overexpression of D-Cbl in the eye of Drosophila embryos inhibits EGFR-dependent photoreceptor cell development. Sli-1 is a negative regulator of the Let-23 receptor tyrosine kinase, an EGFR homolog, in vulva development. Cbl proteins in this subfamily consist of a highly conserved N-terminal half that includes a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain) and a C3HC4-type RING-HC finger, both of which are required for Cbl-mediated downregulation of RTKs, and a divergent C-terminal region.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 256818810 293 EKCTICLsmlEDGEDVRRLPCMHLFHQLCVDQWLAMSKK-CPICR 336
Cdd:cd16502    2 QLCKICA---ENDKDVRIEPCGHLLCTPCLTSWQDSDGQtCPFCR 43

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 256818810 294 KCTICLSmledgedVRR----LPCMHLFHQLCVDQWLAMSKKCPICRVDIETQ 342
Cdd:cd16527    2 KCSLCLE-------ERRhptaTPCGHLFCWSCITEWCNEKPECPLCREPFQPQ 47