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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16667   1 ECAVCKEDFEVGEEVRQLPCKHLFHPDCIVPWLELHNSCPVCR 43

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16667   1 ECAVCKEDFEVGEEVRQLPCKHLFHPDCIVPWLELHNSCPVCR 43

zinc-ribbon;

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 18405411     7 TRYWCHMCSQTVNPVME--AEIKCPFCQSGFVEEM 39
Cdd:pfam14369   1 QRYWCHQCDRFVRIAPSedSDVACPRCGGGFVEEI 35

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 18405411    223 CSVCLDDFEigTEAKLMPCTHKFHSDCLLPWLELHS-SCPVC 263
Cdd:smart00184   1 CPICLEEYL--KDPVILPCGHTFCRSCIRKWLESGNnTCPIC 40

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16667   1 ECAVCKEDFEVGEEVRQLPCKHLFHPDCIVPWLELHNSCPVCR 43

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16454   1 TCAICLEEFKEGEKVRVLPCNHLFHKDCIDPWLEQHNTCPLCR 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16801   1 ECPVCKEDYTVGENVRQLPCNHLFHNDCIVPWLEQHDTCPVCR 43

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 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRYQL 267
Cdd:cd23118   3 CTICLEDFEDGEKLRVLPCQHQFHSECVDQWLRRNPKCPVCRRDA 47

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 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLEL-HSSCPVCR 264
Cdd:cd16448   1 CVICLEEFEEGDVVRLLPCGHVFHLACILRWLESgNNTCPLCR 43

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLE-LHSSCPVCR 264
Cdd:cd16473   6 ECAICLENYQNGDLLRGLPCGHVFHQNCIDVWLErDNHCCPVCR 49

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWL-ELHSSCPVCR 264
Cdd:cd16797   3 CAICLDEYEEGDKLRVLPCSHAYHSKCVDPWLtQTKKTCPVCK 45

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 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRY 265
Cdd:cd16666   1 VCAICLEEYEEGQELRVLPCQHEFHRKCVDPWLLQNHTCPLCLF 44

zinc-ribbon;

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 18405411     7 TRYWCHMCSQTVNPVME--AEIKCPFCQSGFVEEM 39
Cdd:pfam14369   1 QRYWCHQCDRFVRIAPSedSDVACPRCGGGFVEEI 35

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 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16460   2 PCVICHEAFSDGDRLLVLPCAHKFHTQCIGPWLDGQQTCPTCR 44

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16472   4 QCVVCMCDYEKRQLLRVLPCSHEFHAKCIDKWLKTNRTCPICR 46

RING finger, H2 subclass, found in Arabidopsis thaliana NEP1-interacting protein-like 1 (NIPL1) and similar proteins; This subfamily includes Arabidopsis thaliana NIPL1 and MISFOLDED PROTEIN SENSING RING E3 LIGASE 1 (MPSR1). NIPL1, also called RING-H2 finger protein ATL27, may be involved in the early steps of the plant defense signaling pathway. MPSR1 is a cytoplasmic E3 ubiquitin-protein ligase involved in protein quality control (PQC) under proteotoxic stress. It is essential for plant survival under proteotoxic stress. It functions by removing damaged proteins before they form cytotoxic aggregates. It recognizes misfolded proteins selectively and tethers polyubiquitin chains to the proteins directly for subsequent degradation by the 26S proteasome pathway. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 223 CSVCLDDFEIGTEAKLMP-CTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd23119   2 CTICLQDLQVGEIARSLPhCHHTFHLGCVDKWLGRHGSCPVCR 44

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 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRY 265
Cdd:cd16799   2 CAICLEKYIDGEELRVIPCTHRFHKKCVDPWLLQHHTCPHCRH 44

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16673   3 CSVCINEYATGNKLRRLPCAHEFHIHCIDRWLSENSTCPICR 44

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 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRYQL 267
Cdd:cd16798   6 CAICLEEFSEGQELRIISCSHEFHRECVDPWLHQHRTCPLCMFNI 50

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 18405411 218 EETLqCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16680   6 EQTL-CVVCFSDFESRQLLRVLPCNHEFHTKCVDKWLKTNRTCPICR 51

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 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWL-ELHSSCPVCR 264
Cdd:cd16665   3 CAICLDDYEEGDKLRILPCSHAYHCKCIDPWLtKNKRTCPVCK 45

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16674   3 CSVCITEYTEGNKLRKLPCSHEYHVHCIDRWLSENSTCPICR 44

RING finger, H2 subclass, found in RING finger protein 215 (RNF215) and similar proteins; This family includes uncharacterized protein RNF215 and similar proteins. Although its biological function remains unclear, RNF215 shares high sequence similarity with PA-TM-RING ubiquitin ligases, which have 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRY 265
Cdd:cd16670   3 CAVCLDQFYKNQCLRVLPCLHEFHRDCVDPWLLLQQTCPLCKR 45

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDDFEIgtEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd23130   2 VCPICLDDPED--EAITLPCLHQFCYTCILRWLQTSPTCPLCK 42

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 18405411 222 QCSVCLDDFEIGTEAKL-MPCTHKFHSDCLLPWLElhSSCPVCRY 265
Cdd:cd16457   2 TCPVCLERMDESVSGILtILCNHSFHCSCLSKWGD--SSCPVCRY 44

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 18405411   222 QCSVCLDDFEIGTEAKlmPCTHKFHSDCLLPWLELHSSCPVC 263
Cdd:pfam13923   1 MCPICMDMLKDPSTTT--PCGHVFCQDCILRALRAGNECPLC 40

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

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 18405411 223 CSVCLDDFEIGTEAK------LMPCTHKFHSDCLLPWLELHSSCPVCRYQLPA 269
Cdd:cd23117   7 CVICMSDIELPSTNSvrrdymVTPCNHIFHTNCLERWMDIKLECPTCRRPLPP 59

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 18405411 223 CSVCLDDFeiGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRYQLPADE 271
Cdd:cd16683   7 CAICYQEF--TTSARITPCNHYFHALCLRKWLYIQDTCPMCHQKVYIED 53

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 18405411 222 QCSVCLDDFEIGTeAKLMPCTHKFHSDCLLPWLELH--SSCPVCRYQL 267
Cdd:cd23120   3 ECPICLEEMNSGT-GYLADCGHEFHLTCIREWHNKSgnLDCPICRVES 49

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 18405411 204 AKKEAVEALATVKIEET---LQCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHS-SCPVCRYQLP 268
Cdd:COG5540 304 TTKGSLKPLSIERAVEAdkgVECAICMSNFIKNDRLRVLPCDHRFHVGCVDKWLLGYSnKCPVCRTAIP 372

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 18405411    223 CSVCLDDFEigTEAKLMPCTHKFHSDCLLPWLELHS-SCPVC 263
Cdd:smart00184   1 CPICLEEYL--KDPVILPCGHTFCRSCIRKWLESGNnTCPIC 40

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
                ....*....|....*....|....*....|....*....|....*...
gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRYQLPA 269
Cdd:cd16681  12 KCTICLSILEEGEDVRRLPCMHLFHQVCVDQWLITNKKCPICRVDIEA 59

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 18405411 223 CSVCLDDFeigTEAKLMPCTHKFHSDCLLPWLELHSSCPVC 263
Cdd:cd16476   3 CAICYQEM---KEARITPCNHFFHGLCLRKWLYVQDTCPLC 40

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 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCRYQL 267
Cdd:cd16805   9 CAVCIEGYKPNDVVRILPCRHLFHKSCVDPWLLDHRTCPMCKMNI 53

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 18405411 223 CSVCLDDFEIGTeAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16574   4 CPICLDRFENEK-AFLDGCFHAFCFTCILEWSKVKNECPLCK 44

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 18405411   223 CSVCLDDFEigTEAKLMPCTHKFHSDCLLPWLEL-HSSCPVC 263
Cdd:pfam00097   1 CPICLEEPK--DPVTLLPCGHLFCSKCIRSWLESgNVTCPLC 40

RING finger, HC subclass, found in Caenorhabditis elegans RING finger protein NHL-1 and similar proteins; NHL-1 functions as an E3 ubiquitin-protein ligase in the presence of both UBC-13 and UBC-1 within the ubiquitin pathway of Caenorhabditis elegans. It acts in chemosensory neurons to promote stress resistance in distal tissues by the transcription factor DAF-16 activation but is dispensable for the activation of heat shock factor 1 (HSF-1). NHL-1 belongs to the TRIM (tripartite motif)-NHL family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil domain, as well as an NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 18405411 216 KIEETLQCSVCLDDFeigTEAKLMPCTHKFhsdCLLPWLE-----LHSS--CPVCR 264
Cdd:cd16524   1 QIEQLLTCPICLDRY---RRPKLLPCQHTF---CLSPCLEglvdyVTRKlkCPECR 50

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 18405411 223 CSVCLDD-FEIGTEA---------KLMPCTHKFHSDCLLPWLELHSSCPVCRYQLPADEAKTDSVTTTSDN 283
Cdd:COG5243 290 CTICMDEmFHPDHEPlprgldmtpKRLPCGHILHLHCLKNWLERQQTCPICRRPVIFDQSSPTPASPNVRN 360

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
                ....*....|....*....|....*....|....*....|.
gi 18405411 223 CSVCLDDFEIGTEAKLMPCTHKFHSDCLLPWLELHSSCPVC 263
Cdd:cd23122  14 CSICLESFCEADPATVTSCKHEYHLQCILEWSQRSKECPMC 54

RING finger, HC subclass, found in tripartite motif-containing protein 3 (TRIM3); TRIM3, also known as brain-expressed RING finger protein (BERP), RING finger protein 97 (RNF97), or RING finger protein 22 (RNF22), is an E3 ubiquitin-protein ligase involved in the pathogenesis of various cancers. It functions as a tumor suppressor that regulates asymmetric cell division in glioblastoma. It binds to the cdk inhibitor p21(WAF1/CIP1) and regulates its availability that promotes cyclin D1-cdk4 nuclear accumulation. Moreover, TRIM3 plays an important role in the central nervous system (CNS). It is encoded by the gene BERP (brain-expressed RING finger protein), a unique p53-regulated gene that modulates seizure susceptibility and GABAAR cell surface expression. Furthermore, TRIM3 mediates activity-dependent turnover of postsynaptic density (PSD) scaffold proteins GKAP/SAPAP1 and is a negative regulator of dendritic spine morphology. In addition, TRIM3 may be involved in vesicular trafficking via its association with the cytoskeleton-associated-recycling or transport (CART) complex that is necessary for efficient transferrin receptor recycling, but not for epidermal growth factor receptor (EGFR) degradation. It also regulates the motility of the kinesin superfamily protein KIF21B. TRIM3 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 18405411 218 EETLQCSVCLDDFEIgteAKLMPCTHKFHSDCL---LPWLELHSSCPVCR 264
Cdd:cd16768   2 KQFLVCSICLDRYHN---PKVLPCLHTFCERCLqnyIPPQSLTLSCPVCR 48

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 18405411 218 EETLQCSVCLDDFeigTEAKLMPCTHKFHSDCL-LPWLELHS---SCPVCRYQLP 268
Cdd:cd16597   3 EEELTCSICLELF---KDPVTLPCGHNFCGVCIeKTWDSQHGseySCPQCRATFP 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 18405411 221 LQCSVCLDDFEigtEAKLMPCTHKFHSDCLLPWLEL-HSSCPVC 263
Cdd:cd16449   1 LECPICLERLK---DPVLLPCGHVFCRECIRRLLESgSIKCPIC 41

RING finger, HC subclass, found in postreplication repair protein RAD18 and similar proteins; RAD18, also known as HR18 or RING finger protein 73 (RNF73), is an E3 ubiquitin-protein ligase involved in post replication repair of UV-damaged DNA via its recruitment to stalled replication forks. It associates to the E2 ubiquitin conjugating enzyme UBE2B to form the UBE2B-RAD18 ubiquitin ligase complex involved in mono-ubiquitination of DNA-associated PCNA on K164. It also interacts with another E2 ubiquitin conjugating enzyme RAD6 to form a complex that monoubiquitinates proliferating cell nuclear antigen at stalled replication forks in DNA translesion synthesis. Moreover, Rad18 is a key factor in double-strand break DNA damage response (DDR) pathways via its association with K63-linked polyubiquitylated chromatin proteins. It can function as a mediator for DNA damage response signals to activate the G2/M checkpoint in order to maintain genome integrity and cell survival after ionizing radiation (IR) exposure. RAD18 contains a C3HC4-type RING-HC finger, a ubiquitin-binding zinc finger domain (UBZ), a SAP (SAF-A/B, Acinus and PIAS) domain, and a RAD6-binding domain (R6BD).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 18405411 217 IEETLQCSVCLDDFEigTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16529   1 LDDLLRCPICFEYFN--TAMMITQCSHNYCSLCIRRFLSYKTQCPTCR 46

RING finger, H2 subclass, found in RING finger protein 32 (RNF32) and similar proteins; RNF32 is mainly expressed in testis spermatogenesis, most likely in spermatocytes and/or in spermatids, suggesting a possible role in sperm formation. RNF32 contains two C3H2C3-type RING-H2 fingers separated by an IQ domain of unknown function. Although the biological function of RNF32 remains unclear, proteins with double RING-H2 fingers may act as scaffolds for binding several proteins that function in the same pathway.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 18405411 222 QCSVCLDDFEiGTEAKLMPCTHKFHSDCLLPWLELHSS----CPVCR 264
Cdd:cd16471   1 ECPICLCAFK-GRKCTLLSCSHVFHEACLSAFEKFIESknqkCPLCR 46

RING finger, HC subclass, found in tripartite motif-containing protein TRIM65 and similar proteins; TRIM65 is an E3 ubiquitin-protein ligase that interacts with the innate immune receptor MDA5, enhancing its ability to stimulate interferon-beta signaling. It functions as a potential oncogenic protein that negatively regulates p53 through ubiquitination, providing insight into the development of novel approaches targeting TRIM65 for non-small cell lung carcinoma (NSCLC) treatment, and also overcoming chemotherapy resistance. Moreover, TRIM65 negatively regulates microRNA-driven suppression of mRNA translation by targeting TNRC6 proteins for ubiquitination and degradation. TRIM65 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 18405411 218 EETLQCSVCLddfEIGTEAKLMPCTHKFHSDCLLPWLELHS----SCPVCR 264
Cdd:cd16609   1 EEELTCSICL---GLYQDPVTLPCQHSFCRACIEDHWRQKDegsfSCPECR 48

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM13, TRIM59 and similar proteins; TRIM13 and TRIM59, two closely related tripartite motif-containing proteins, belong to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, followed by a C-terminal transmembrane domain. TRIM13, also known as B-cell chronic lymphocytic leukemia tumor suppressor Leu5, leukemia-associated protein 5, putative tumor suppressor RFP2, RING finger protein 77 (RNF77), or Ret finger protein 2, is an endoplasmic reticulum (ER) membrane anchored E3 ubiquitin-protein ligase that interacts with proteins localized to the ER, including valosin-containing protein (VCP), a protein indispensable for ER-associated degradation (ERAD). TRIM59, also known as RING finger protein 104 (RNF104) or tumor suppressor TSBF-1, is a putative E3 ubiquitin-protein ligase that functions as a novel multiple cancer biomarker for immunohistochemical detection of early tumorigenesis.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 18405411 219 ETLQCSVCLDDFEigtEAKLMPCTHKFHSDCL-------LPWLELHSSCPVCR 264
Cdd:cd16581   1 EELTCSICYNIFD---DPKILPCSHTFCKNCLekllaasGYYLLASLKCPTCR 50

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18405411 222 QCSVCLDdfeiGTEAKLMPCTHKFHSDCLLPWLELHSSCPVCR 264
Cdd:cd16545   2 ECCICMD----RKADLILPCAHSYCQKCIDKWSDRHRTCPICR 40

RING finger, H2 subclass, found in RING finger protein 25 (RNF25) and similar proteins; RNF25, also known as AO7, is a putative E3 ubiquitin-protein ligase that was initially identified as an interacting protein of the E2 ubiquitin-conjugating enzyme, Ubc5B. It is ubiquitously expressed in various tissues and predominantly localized in the nucleus. RNF25 activates the nuclear factor (NF)-kappaB-dependent gene expression upon stimulation with Interleukin-1 beta (IL-1beta), or tumor necrosis factor (TNF), or overexpression of NF-kappaB-inducing kinase. It interacts with the p65 transactivation domain (TAD) and modulates its transcriptional activity. RNF25 contains an N-terminal RWD domain, a C3H2C3-type RING-H2 finger, and a C-terminal Pro-rich region. Both the RING-H2 finger and the C-terminal regions of RNF25 are necessary for transcriptional activation.

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gi 18405411 222 QCSVCLDDFEIGTEAKLMPCTHKFHSDCLL--------------------PWLELHSS-----CPVCR 264
Cdd:cd16470   4 QCVICLYGFQEGDAFTKTPCYHYFHSHCLAryiqhmeenlkeeqeeqeerPRAQTEQEqfqvlCPVCR 71

RING finger, HC subclass, found in tripartite motif-containing protein 35 (TRIM35) and similar proteins; TRIM35, also known as hemopoietic lineage switch protein 5 (HLS5), is a putative hepatocellular carcinoma (HCC) suppressor that inhibits phosphorylation of pyruvate kinase isoform M2 (PKM2), which is involved in aerobic glycolysis of cancer cells and further suppresses the Warburg effect and tumorigenicity in HCC. It also negatively regulates Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon production by suppressing the stability of interferon regulatory factor 7 (IRF7). Moreover, TRIM35 regulates erythroid differentiation by modulating globin transcription factor 1 (GATA-1) activity. TRIM35 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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gi 18405411 217 IEETLQCSVCLDDFEigtEAKLMPCTHKFHSDCL-LPW-LELHSSCPVCRYQLPADEAKTDSV 277
Cdd:cd16599   1 FKEELLCPICYEPFR---EAVTLRCGHNFCKGCVsRSWeRQPRAPCPVCKEASSSDDLRTNHT 60