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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 755545181 290 DSHQSEQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRADASEVPREAE 351
Cdd:cd16680    1 ENHQSEQTLCVVCFSDFESRQLLRVLPCNHEFHTKCVDKWLKTNRTCPICRADASEVHRDAE 62

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 755545181 290 DSHQSEQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRADASEVPREAE 351
Cdd:cd16680    1 ENHQSEQTLCVVCFSDFESRQLLRVLPCNHEFHTKCVDKWLKTNRTCPICRADASEVHRDAE 62

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

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                 ....*....|....*....|....*....|....*....|....*....|
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANR-TCPICRadaSEVP 347
Cdd:COG5540  326 CAICMSNFIKNDRLRVLPCDHRFHVGCVDKWLLGYSnKCPVCR---TAIP 372

N1R/p28-like protein; Provisional

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                 ....*....|....*....|....*...
gi 755545181 314 VLP-CNHEFHAKCVDKWLKANRTCPICR 340
Cdd:PHA02929 196 ILSnCNHVFCIECIDIWKKEKNTCPVCR 223

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 755545181 290 DSHQSEQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRADASEVPREAE 351
Cdd:cd16680    1 ENHQSEQTLCVVCFSDFESRQLLRVLPCNHEFHTKCVDKWLKTNRTCPICRADASEVHRDAE 62

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.

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                 ....*....|....*....|....*....|....*....|....*.
gi 755545181 295 EQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16472    1 DQTQCVVCMCDYEKRQLLRVLPCSHEFHAKCIDKWLKTNRTCPICR 46

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.

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                 ....*....|....*....|....*....|....*....|..
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16454    2 CAICLEEFKEGEKVRVLPCNHLFHKDCIDPWLEQHNTCPLCR 43

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.

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                 ....*....|....*....|....*....|....*....|...
gi 755545181 299 CVVCFSDFEVRQLLRVLP-CNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16461    2 CAICLSDYENGEELRRLPeCKHAFHKECIDEWLKSNSTCPLCR 44

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

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gi 755545181 293 QSEQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWL-KANRTCPICRADAS 344
Cdd:cd16473    1 MLECEECAICLENYQNGDLLRGLPCGHVFHQNCIDVWLeRDNHCCPVCRWPVY 53

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

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                 ....*....|....*....|....*....|....*....|....*.
gi 755545181 298 LCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRADA 343
Cdd:cd16469    2 TCAVCLEEFKLKEELGVCPCGHAFHTKCLKKWLEVRNSCPICKSPV 47

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 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16673    3 CSVCINEYATGNKLRRLPCAHEFHIHCIDRWLSENSTCPICR 44

RING finger, H2 subclass, found in RING finger protein 12 (RNF12) and similar proteins; 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. Its functional activity is regulated by phosphorylation-dependent nucleocytoplasmic shuttling. It is negatively regulated by pluripotency factors in embryonic stem cells. p53 represses its transcription through Sp1. RNF12 is the primary factor responsible for X chromosome inactivation (XCI) in female placental mammals. It is an indispensable factor in up-regulation of Xist transcription, thereby leading to initiation of random XCI. It also targets REX1, an inhibitor of XCI, for proteasomal degradation. RNF12 also acts as a co-regulator for a range of transcription factors, particularly those containing a LIM homeodomain, and modulates the formation of transcriptional multiprotein complexes. It is a negative regulator of Smad7, which in turn negatively regulates the signaling of type I receptors from the transforming growth factor beta (TGF-beta) superfamily. In addition, paternal RNF12 is a critical survival factor for milk-producing alveolar cells. RNF12 contains an nuclear localization signal (NLS) and a C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|..
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16674    3 CSVCITEYTEGNKLRKLPCSHEYHVHCIDRWLSENSTCPICR 44

Ring finger domain;

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                  ....*....|....*....|....*....|....*....|..
gi 755545181  299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:pfam13639   3 CPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

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.

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gi 755545181 297 TLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRA 341
Cdd:cd16460    1 TPCVICHEAFSDGDRLLVLPCAHKFHTQCIGPWLDGQQTCPTCRL 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.

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                 ....*....|....*....|....*....|....*....|....
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRAD 342
Cdd:cd16804    2 CAVCIENYKSKDVVRILPCKHVFHRICIDPWLLEHRTCPMCKLD 45

RING finger, H2 subclass, found in RING finger proteins RNF126, RNF115, and similar proteins; This subfamily includes RING finger proteins RNF126, RNF115, and similar proteins. RNF126 is a Bag6-dependent E3 ubiquitin ligase that is involved in the mislocalized protein (MLP) pathway of quality control. It regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). RNF126 promotes cancer cell proliferation by targeting the tumor suppressor p21 for ubiquitin-mediated degradation, and could be a novel therapeutic target in breast and prostate cancers. It is also able to ubiquitylate cytidine deaminase (AID), a poorly soluble protein that is essential for antibody diversification. RNF115, also known as Rab7-interacting ring finger protein (Rabring 7), or zinc finger protein 364 (ZNF364), or breast cancer-associated gene 2 (BCA2), is an E3 ubiquitin-protein ligase that is an endogenous inhibitor of adenosine monophosphate-activated protein kinase (AMPK) activation; this inhibition increases the efficacy of metformin in breast cancer cells. It also functions as a cofactor in the restriction imposed by tetherin on HIV-1, and targets HIV-1 Gag for lysosomal degradation, impairing virus assembly and release, in a tetherin-independent manner. Moreover, RNF115 is a Rab7-binding protein that stimulates c-Myc degradation through mono-ubiquitination of MM-1. It also plays crucial roles as a Rab7 target protein in vesicle traffic to late endosome/lysosome and lysosome biogenesis. RNF115 and RNF126 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. Both of them contain an N-terminal BCA2 Zinc-finger domain (BZF), AKT-phosphorylation sites, and a C-terminal C3H2C3-type RING-H2 finger.

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gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16667    2 CAVCKEDFEVGEEVRQLPCKHLFHPDCIVPWLELHNSCPVCR 43

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.

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gi 755545181 298 LCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWL-KANRTCPICR 340
Cdd:cd16665    2 VCAICLDDYEEGDKLRILPCSHAYHCKCIDPWLtKNKRTCPVCK 45

RING finger, H2 subclass, found in RING finger protein 13 (RNF13) and similar proteins; RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that is functionally significant 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. It functions as an important regulator of inositol-requiring transmembrane kinase/endonuclease IRE1alpha, mediating endoplasmic reticulum (ER) stress-induced apoptosis through the activation of the IRE1alpha-TRAF2-JNK signaling pathway. Moreover, RNF13 is involved in the regulation of the soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) complex via the ubiquitination of snapin, a SNAP25-interacting protein, which thereby controls synaptic function. In addition, RNF13 participates in regulating the function of satellite cells by modulating cytokine composition. RNF13 is evolutionarily conserved among many metazoans and 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 755545181 295 EQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWL-KANRTCPICR 340
Cdd:cd16796    7 EYDVCAICLDEYEEGDKLRILPCSHAYHCKCVDPWLtKTKKTCPVCK 53

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.

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gi 755545181 294 SEQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPIC 339
Cdd:cd16798    1 SSAPVCAICLEEFSEGQELRIISCSHEFHRECVDPWLHQHRTCPLC 46

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

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gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANR-TCPICRadaSEVP 347
Cdd:COG5540  326 CAICMSNFIKNDRLRVLPCDHRFHVGCVDKWLLGYSnKCPVCR---TAIP 372

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

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gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPIC 339
Cdd:cd16676    3 CAVCLEDFKTKDELGVLPCQHAFHRKCLVKWLEIRCVCPMC 43

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.

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gi 755545181 298 LCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPIC 339
Cdd:cd16675    2 ICAVCLEEFKPKDELGICPCKHAFHRKCLIKWLEVRKVCPLC 43

RING finger, H2 subclass, found in RING finger protein 126 (RNF126) and similar proteins; RNF126 is a Bag6-dependent E3 ubiquitin ligase that is involved in the mislocalized protein (MLP) pathway of quality control. It regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). Moreover, RNF126 promotes cancer cell proliferation by targeting the tumor suppressor p21 for ubiquitin-mediated degradation, and could be a novel therapeutic target in breast and prostate cancers. It is also able to ubiquitylate cytidine deaminase (AID), a poorly soluble protein that is essential for antibody diversification. In addition, RNF126 and the related protein, RNF115 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. RNF126 contains an N-terminal BCA2 Zinc-finger domain (BZF), the AKT-phosphorylation sites, and the C-terminal C3H2C3-type RING-H2 finger.

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gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16801    2 CPVCKEDYTVGENVRQLPCNHLFHNDCIVPWLEQHDTCPVCR 43

RING finger, H2 subclass, found in protein E3 ubiquitin-protein ligase Praja-1, Praja-2, and similar proteins; This family includes two highly similar E3 ubiquitin-protein ligases, Praja-1 and Praja-2. Praja-1, also known as RING finger protein 70, is a RING-H2 finger ubiquitin ligase encoded by gene PJA1, a novel human X chromosome gene abundantly expressed in the brain. It has been implicated in bone and liver development, as well as memory formation and X-linked mental retardation (MRX). Praja-1 interacts with and activates the ubiquitin-conjugating enzyme UbcH5B, and shows E2-dependent E3 ubiquitin ligase activity. It is a 3-deazaneplanocin A (DZNep)-induced ubiquitin ligase that directly ubiquitinates individual polycomb repressive complex 2 (PRC2) subunits in a cell free system, which leads to their proteasomal degradation. It also plays an important role in neuronal plasticity, which is the basis for learning and memory. Moreover, Praja-1 ubiquitinates embryonic liver fodrin (ELF) and Smad3, but not Smad4, in a transforming growth factor-beta (TGF-beta)-dependent manner. It controls ELF abundance through ubiquitin-mediated degradation, and further regulates TGF-beta signaling, which plays a key role in the suppression of gastric carcinoma. Praja-1 also regulates the transcription function of the homeodomain protein Dlx5 by controlling the stability of Dlxin-1, via a ubiquitin-dependent degradation pathway. Praja-2, also known as RING finger protein 131, NEURODAP1, or KIAA0438, is an E2-dependent E3 ubiquitin ligase that interacts with and activates the ubiquitin-conjugating enzyme UbcH5B. It functions as an A-kinase anchoring protein (AKAP)-like E3 ubiquitin ligase that plays a critical role in controlling cyclic AMP (cAMP)-dependent PKA activity and pro-survival signaling, and further promotes cell proliferation and growth. Praja-2 is also involved in protein sorting at the postsynaptic density region of axosomatic synapses and possibly plays a role in synaptic communication and plasticity. Together with the AMPK-related kinase SIK2 and the CDK5 activator CDK5R1/p35, it forms a SIK2-p35-PJA2 complex that plays an essential role for glucose homeostasis in pancreatic beta cell functional compensation. Praja-2 ubiquitylates and degrades Mob, a core component of NDR/LATS kinase and a positive regulator of the tumor-suppressor Hippo signaling. Both Praja-1 and Praja-2 contain a potential nuclear localization signal (NLS) and a C-terminal C3H2C3-type RING-H2 motif.

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                 ....*....|....*....|....*....|....*....|..
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16465    2 CPICCSEYVKDEIATELPCHHLFHKPCITAWLQKSGTCPVCR 43

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
                 ....*....|....*....|....*....|....*....|....
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRAD 342
Cdd:cd16805    9 CAVCIEGYKPNDVVRILPCRHLFHKSCVDPWLLDHRTCPMCKMN 52

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 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16799    2 CAICLEKYIDGEELRVIPCTHRFHKKCVDPWLLQHHTCPHCR 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 755545181   299 CVVCFSDFEvrQLLRVLPCNHEFHAKCVDKWLKA-NRTCPIC 339
Cdd:smart00184   1 CPICLEEYL--KDPVILPCGHTFCRSCIRKWLESgNNTCPIC 40

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 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRADA 343
Cdd:cd23113    5 CCICQEEYEEGDELGTIECGHEYHSDCIKQWLVQKNLCPICKATA 49

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 755545181 298 LCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16480    1 YCTICSDFFDNSRDVAAIHCGHTFHYDCLLQWFDTSRTCPQCR 43

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 755545181 298 LCVVCFSDFevrQLLRVLPCNHEFHAKCVDKWLKANRTCPIC 339
Cdd:cd16476    2 VCAICYQEM---KEARITPCNHFFHGLCLRKWLYVQDTCPLC 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 755545181 299 CVVCFSDFEVRQllRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16479    4 CIICREEMTVGA--KKLPCGHIFHLSCLRSWLQRQQTCPTCR 43

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 755545181 299 CVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKA-NRTCPICR 340
Cdd:cd23123    3 CCICLDKLKTGEEVKKLDCRHKFHKQCIEGWLKHlNFNCPLCR 45

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        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 755545181 295 EQTLCVVCFSDFEVRQLLRV--LPCNHEFHAKCVDKWLK-ANRTCPICRADA 343
Cdd:cd16450    1 EGNTCPICFEPWTSSGEHRLvsLKCGHLFGYSCIEKWLKgKGKKCPQCNKKA 52

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 755545181 299 CVVCFSDFEvRQLLRVLPCNHEFHAKCVDKWLKA--NRTCPICRADAS 344
Cdd:cd23120    4 CPICLEEMN-SGTGYLADCGHEFHLTCIREWHNKsgNLDCPICRVESL 50

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 755545181 298 LCVVCFSDFEvRQLLRVLPCNHEFHAKCVDKWLKANRTCPICRA 341
Cdd:cd16574    3 SCPICLDRFE-NEKAFLDGCFHAFCFTCILEWSKVKNECPLCKQ 45

RING finger, H2 subclass, found in RING finger protein 145 (RNF145) and similar proteins; 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, 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. Like RNF139, RNF145 contains a C3H2C3-type RING-H2 finger with possible E3-ubiquitin ligase activity.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 755545181 298 LCVVCFSDFEVRQllrVLPCNHEFHAKCVDKWLKANRTCPIC 339
Cdd:cd16684    4 ICSICYQDMKSAV---ITPCSHFFHAGCLKKWLYVQETCPLC 42

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 755545181  299 CVVCFSDFEvrQLLRVLPCNHEFHAKCVDKWLKA-NRTCPIC 339
Cdd:pfam00097   1 CPICLEEPK--DPVTLLPCGHLFCSKCIRSWLESgNVTCPLC 40

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 755545181 298 LCVVCFSDFevrQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16532    2 ICPICQDEF---KDPVVLRCKHIFCEDCVSEWFERERTCPLCR 41

Modified RING-CH finger, H2 subclass (C4HC2H-type), found in zinc/RING finger protein 2 (ZNRF2) and similar proteins; ZNRF2, also known as protein Ells2 or RING finger protein 202 (RNF202), is an E3 ubiquitin-protein ligase that is highly expressed in the nervous system during development and is present in presynaptic plasma membranes. It is N-myrisotoylated and is also located in the endosome-lysosome compartment in fibroblasts. It contains an N-terminal MAGE domain, and a special C-terminal domain that combines a zinc finger and a modified C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of RING-H2 finger. Only the RING finger of the zinc finger-RING finger motif is required for its E3 ubiquitin ligase activity. Together with its sister protein ZNRF1, ZNRF2 regulates the ubiquitous Na+/K+ pump (Na+/K+ATPase).

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 755545181 287 FNPDSHQSEQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCP 337
Cdd:cd16695    1 YNEDVLSKDAGECAICLEELQQGDTIARLPCLCIYHKGCIDEWFEVNRSCP 51

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 755545181 298 LCVVCfsdfevRQLLR---VLPCNHEFHAKCVDKWLKANRTCPICRAD 342
Cdd:cd16547    5 ICSIC------HGVLRcpvRLSCSHIFCKKCILQWLKRQETCPCCRKE 46

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
                 ....*....|....*....|....*....
gi 755545181 314 VLPCNHEFHAKCVDKWLKANRTCPICRAD 342
Cdd:cd16535   16 TLNCSHSFCSYCITEWMKRKKECPICRKP 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 755545181 299 CVVCFsdfEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16455    3 CAICW---ESMQSARKLPCGHLFHNSCLRSWLEQDTSCPTCR 41

modified RING finger, H2 subclass (C3H2C2D-type), found in RING-box protein 1 (RBX1) and similar proteins; RBX1, also known as Hrt1, protein ZYP, RING finger protein 75 (RNF75), or regulator of cullins 1 (ROC1), is an E3 ubiquitin-protein ligase necessary for ubiquitin ligation activity of multimeric cullin (Cul)-RING E3 ligases (CRLs). RBX1-containing CRLs are involved in the NEDD8 pathway; RBX1 specifically regulates NEDD8ylation of Cul1-4. It can also bind and activate HIV-1 Vif-Cullin5 E3 ligase complex in vitro. Moreover, RBX1 is an essential element of Skp1/Cullin/F-box (SCF) E3-ubiquitin ligase complexes that target diverse proteins for proteasome-mediated degradation. It is a direct functional target of miR-194 and plays an important role in proliferation and migration of gastric cancer (GC) cells. RBX1 is also an essential component of KEAP1/CUL3/RBX1 E3-ubiquitin ligase complex that functions as a regulator of NFE2-related factor 2 (NRF2) and plays a key role in NRF2 pathway deregulation in multiple tumor types, including ovarian carcinomas (OVCA) and papillary thyroid carcinoma (PTC). Furthermore, RBX1 associates with DDB1, Cul4A, and Fbxw5 to form the Fbxw5-DDB1-Cul4A-Rbx1 complex that may function as a dual SUMO/ubiquitin ligase suppressing c-Myb activity through sumoylation or ubiquitination. RBX1 contains a C-terminal modified RING-H2 finger that is of C3H2C2D-type, rather than the canonical C3H2C3-type. The modified RING-H2 finger is essential for its ligase activity.

                         10        20
                 ....*....|....*....|....*.
gi 755545181 317 CNHEFHAKCVDKWLKANRTCPICRAD 342
Cdd:cd16485   36 CNHAFHFHCISRWLKTRQVCPLDNRE 61

Component of SCF ubiquitin ligase and anaphase-promoting complex [Posttranslational modification, protein turnover, chaperones / Cell division and chromosome partitioning];

                         10        20
                 ....*....|....*....|....
gi 755545181 317 CNHEFHAKCVDKWLKANRTCPICR 340
Cdd:COG5194   54 CNHAFHDHCIYRWLDTKGVCPLDR 77

RING finger, H2 subclass, found in anaphase-promoting complex subunit 11 (APC11) and similar proteins; APC11, also known as cyclosome subunit 11, or hepatocellular carcinoma-associated RING finger protein, is a C3H2C3-type RING-H2 protein that facilitates ubiquitin chain formation by recruiting ubiquitin-charged ubiquitin conjugating enzymes (E2) through its RING-H2 domain. APC11 and its partner, the cullin-like subunit APC2, form the dynamic catalytic core of the gigantic, multisubunit 1.2-MDa anaphase-promoting complex/cyclosome (APC), also known as the cyclosome, which is a ubiquitin-protein ligase (E3) composed of at least 12 subunits and controls cell division by ubiquitinating cell cycle regulators, such as cyclin B and securin, to drive their timely degradation. APC11 can be inhibited by hydrogen peroxide, which may contribute to the delay in cell cycle progression through mitosis that is characteristic of cells subjected to oxidative stress. APC11 contains a canonical RING-H2-finger that coordinate two Zn2+ ions. In addition, it contains a third Zn2+-binding site that is not essential for its ligase activity.

                         10        20
                 ....*....|....*....|....*....
gi 755545181 317 CNHEFHAKCVDKWLKANR---TCPICRAD 342
Cdd:cd16456   32 CSHCFHMHCILKWLNSQQvqqHCPMCRQE 60

RING finger, H2 subclass, found in Arabidopsis thaliana protein ABA INSENSITIVE RING PROTEIN 1 (AIRP1) and similar proteins; This subfamily includes Arabidopsis thaliana AIRP1 and RING-H2 finger B1a (RHB1A). AIRP1, also known as RING-type E3 ubiquitin transferase AIRP1, possesses E3 ubiquitin-protein ligase activity in vitro when associated with the E2 enzyme UBC8. It plays combinatory roles with AIRP2 in the positive regulation of the abscisic acid-mediated drought stress response. RHB1A is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 755545181 295 EQTLCVVCFSDFEVRQLLRVLPCNHEFHAKCVDKWLKANRTCPIC 339
Cdd:cd23116    1 DEDVCPTCLEGYTEENPKLLTKCGHHFHLACIYEWMERSERCPVC 45

RING finger, H2 subclass, found in 43 kDa receptor-associated protein of the synapse (Rapsyn) and similar proteins; Rapsyn, also known as acetylcholine receptor (AChR)-associated 43 kDa protein or RING finger protein 205 (RNF205), is a 43 kDa postsynaptic protein that plays an essential role in the clustering and maintenance of AChR in the postsynaptic membrane of the motor endplate. AChRs enable the transport of rapsyn from the Golgi complex to the plasma membrane through a molecule-specific interaction. Rapsyn also mediates subsynaptic anchoring of protein kinase A (PKA) type I in close proximity to the postsynaptic membrane, which is essential for synapse maintenance. Its mutations in humans cause endplate AChR deficiency and myasthenic syndrome. Rapsyn contains an N-terminal myristoylation signal required for membrane association, seven tetratricopeptide repeats (TPRs) that subserve rapsyn self-association, a coiled-coil domain responsible for the binding of determinants within the long cytoplasmic loop of each AChR subunit, a C3H2C3-type RING-H2 finger that binds to the cytoplasmic domain of beta-dystroglycan and to S-NRAP and links rapsyn to the subsynaptic cytoskeleton, and a serine phosphorylation site.

                         10        20        30
                 ....*....|....*....|....*....|....*
gi 755545181 307 EVRQLLRVLPCNHEFHAKCVDKWLK-ANRTCPICR 340
Cdd:cd16478   13 EKNEQLQALPCSHIFHLKCLQTNLRgGTRGCPNCR 47

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

                         10        20
                 ....*....|....*....|....*...
gi 755545181 316 PCNHEFHAKCVDKWL-KANRTCPICRAD 342
Cdd:cd23138   19 PCGHNFCLKCFQKWMgQGKKTCGTCRSP 46

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 755545181 299 CVVCFSDFEVRQLLRvlPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16506    3 CPICLDEIQNKKTLE--KCKHSFCEDCIDRALQVKPVCPVCG 42

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 755545181 298 LCVVCFSDFevrQLLRVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16741   16 ICAICQAEF---RKPILLICQHVFCEECISLWFNREKTCPLCR 55

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
                 ....*....|....*....|....*....|....
gi 755545181 314 VLPCNHEFHAKCVDKWL-KANRTCPICRADASEV 346
Cdd:cd16503   18 LQPCMHNFCAACYSDWMeRSNTECPTCRATVQRV 51

RING finger, HC subclass, found in RING finger protein 219 (RNF219) and similar proteins; RNF219 may function as a modulator of late-onset Alzheimer's disease (LOAD) associated amyloid beta A4 precursor protein (APP) endocytosis and metabolism. It genetically interacts with apolipoprotein E epsilon4 allele (APOE4). Thus, a genetic variant of RNF219 was found to affect amyloid deposition in human brain and LOAD age-of-onset. Moreover, common genetic variants at the RNF219 locus had been associated with alternations in lipid metabolism, cognitive performance and central nervous system ventricle volume. RNF219 contains a C3HC4-type RING-HC finger.

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gi 755545181 299 CVVCFSdfEVRQLLrVLPCNHEFHAKCVDKWLKANRTCPICR 340
Cdd:cd16562    4 CHICLG--KVRQPV-ICSNNHVFCSSCMDVWLKNNNQCPACR 42