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 1063715407 108 EECGICMEMNNMVVLPnCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16545     1 EECCICMDRKADLILP-CAHSYCQKCIDKWSDRHRTCPICR 40

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 1063715407 108 EECGICMEMNNMVVLPnCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16545     1 EECCICMDRKADLILP-CAHSYCQKCIDKWSDRHRTCPICR 40

Ring finger domain;

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                  ....*....|....*....|....*....|....*....|...
gi 1063715407 109 ECGICMEM---NNMVVLPNCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:pfam13639   2 ECPICLEEfeeGDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

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 1063715407  110 CGICME--MNNMVVLPnCTHSLCIKCYRDW-HGRSESCPFC 147
Cdd:smart00184   1 CPICLEeyLKDPVILP-CGHTFCRSCIRKWlESGNNTCPIC 40

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.

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                  ....*....|....*....|....*....|....*....|.
gi 1063715407 108 EECGICMEMNNMVVLPnCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16545     1 EECCICMDRKADLILP-CAHSYCQKCIDKWSDRHRTCPICR 40

N1R/p28-like protein; Provisional

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                  ....*....|....*....|....*....|....*....|....*....|....
gi 1063715407 103 DIEREEECGICME------MNNMV--VLPNCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:PHA02929  170 NRSKDKECAICMEkvydkeIKNMYfgILSNCNHVFCIECIDIWKKEKNTCPVCR 223

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

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                  ....*....|....*....|....*....|....*....|....*.
gi 1063715407 107 EEECGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCRDSLK 152
Cdd:cd16535     1 ELQCSICSELFIEAVTLNCSHSFCSYCITEWMKRKKECPICRKPIT 46

RING finger, HC subclass, found in makorin-1 (MKRN1), makorin-3 (MKRN3), and similar proteins; MKRN1, also known as makorin RING finger protein 1 or RING finger protein 61 (RNF61), is an E3 ubiquitin-protein ligase targeting the telomerase catalytic subunit (TERT) for proteasome processing. It regulates the ubiquitination and degradation of peroxisome-proliferator-activated receptor gamma (PPARgamma), a nuclear receptor that is linked to obesity and metabolic diseases. It also mediates the posttranslational regulation of p14ARF, and thus potentially regulates cellular senescence and tumorigenesis in gastric cancer. Moreover, MKRN1 functions as a differentially negative regulator of p53 and p21, and controls cell cycle arrest and apoptosis. It induces degradation of West Nile virus (WNV) capsid protein to protect cells from WNV. It is a RNA-binding protein involved in the modulation of cellular stress and apoptosis. It predominantly associates with proteins involved in mRNA metabolism including regulators of mRNA turnover, transport, and/or translation, and acts as a component of a ribonucleoprotein complex in embryonic stem cells (ESCs) that is recruited to stress granules upon exposure to environmental stress. MKRN1 interacts with poly(A)-binding protein (PABP), a key component of different ribonucleoprotein complexes, in an RNA-independent manner, and stimulates translation in nerve cells. In addition, MKRN1 is a novel SEREX (serological identification of antigens by recombinant cDNA expression cloning) antigen of esophageal squamous cell carcinoma (SCC). It may be involved in carcinogenesis of the well-differentiated type of tumors possibly via ubiquitination of filamin A interacting protein 1 (L-FILIP). Human MKRN1 contains three N-terminal C3H1-type zinc fingers, a motif rich in Cys and His residues (CH), a C3HC4-type RING-HC finger, and another C3H1-type zinc finger at the C-terminus. MKRN3, also known as makorin RING finger protein 3, RING finger protein 63 (RNF63), or zinc finger protein 127 (ZNF127), is a therian mammal-specific retrocopy of MKRN1. It acts as a putative E3 ubiquitin-protein ligase involved in ubiquitination and cell signaling. MKRN3 shows a potential inhibitory effect on hypothalamic gonadotropin-releasing hormone (GnRH) secretion. Its defects represent the most frequent known genetic cause of familial central precocious puberty (CPP). In contrast to human MKRN1, human MKRN3 lacks the second C3H1-type zinc finger at the N-terminal region. The RING-HC finger of mammalian MKRN4 shows high sequence similarity with that of MKRN3, and is also included in this model.

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                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1063715407 110 CGICMEM---------NNMVVLPNCTHSLCIKCYRDWHGRSE-------SCPFCR 148
Cdd:cd16730     4 CGICMEVvyekanpseRRFGILSNCNHTYCLKCIRKWRSAKQfeskiikSCPECR 58

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

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1063715407 107 EEE--CGICMEM-NNMVVLPnCTHSLCIKCYRD-WHGRSE---SCPFCRD 149
Cdd:cd16609     1 EEEltCSICLGLyQDPVTLP-CQHSFCRACIEDhWRQKDEgsfSCPECRA 49

zinc finger-like protein; Provisional

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1063715407 104 IEREEECGICMEM---------NNMVVLPNCTHSLCIKCYRDWH------GRSESCPFCRDSLKRVNSGDLWMLM 163
Cdd:PHA02926  167 VSKEKECGICYEVvyskrlendRYFGLLDSCNHIFCITCINIWHrtrretGASDNCPICRTRFRNITMSKFYKLV 241

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.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1063715407 108 EECGICME-MNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCRDSLKRV 154
Cdd:cd23130     1 DVCPICLDdPEDEAITLPCLHQFCYTCILRWLQTSPTCPLCKTPVTSI 48

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

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1063715407 106 REEECGICME-MNNMVVLPnCTHSLCIKCYRDWHGRSESCPFCRDSLKRVN 155
Cdd:cd16561     1 GEQECSICLEdLNDPVKLP-CDHVFCEECIRQWLPGQMSCPLCRTELPDDF 50

RING finger, HC subclass, found in makorin-4 (MKRN4) and similar proteins; MKRN4, also known as makorin RING finger protein pseudogene 4, makorin RING finger protein pseudogene 5, RING finger protein 64 (RNF64), zinc finger protein 127-Xp (ZNF127-Xp), or zinc finger protein 127-like 1, is a new divergent member of the makorin protein family in vertebrates. It may have an ancestral gonad-specific function and maternal embryonic expression before duplication in vertebrates. MKRN4 contains typical arrays of one to four C3H1-type zinc fingers, a motif rich in Cys and His residues (CH) and a C3HC4-type RING-HC finger. The RING-HC finger of mammalian MKRN4 shows high sequence similarity with that of MKRN3, and is not included in this model.

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                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1063715407 110 CGICMEM---------NNMVVLPNCTHSLCIKCYRDWHGRSE-------SCPFCR 148
Cdd:cd16732     4 CGICMDKvyekahakeRVFGILPNCNHAFCVGCIKKWRKSKDfqnevikACPQCR 58

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 1063715407  110 CGICME--MNNMVVLPnCTHSLCIKCYRDW-HGRSESCPFC 147
Cdd:smart00184   1 CPICLEeyLKDPVILP-CGHTFCRSCIRKWlESGNNTCPIC 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.

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                  ....*....|....*....|....*....|....*....|...
gi 1063715407 110 CGICMEmnNMVV----LPnCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16479     4 CIICRE--EMTVgakkLP-CGHIFHLSCLRSWLQRQQTCPTCR 43

RING finger, HC subclass, found in Arabidopsis thaliana protein XB3 homolog 5 (XBAT35) and similar proteins; XBAT35, also known as ankyrin repeat domain and RING finger-containing protein XBAT35, or RING-type E3 ubiquitin transferase XBAT35, has no E3 ubiquitin-protein ligase activity observed when associated with the E2 enzyme UBC8 in vitro. It contains a typical C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1063715407 106 REEECGICMEMNNMVVLPNCTH-SLCIKCYRDWHGRSESCPFCRDSLKRV 154
Cdd:cd23129     1 QRDECVVCMDAPRDAVCVPCGHvAGCMSCLKALMQSSPLCPICRAPVRQV 50

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.

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                  ....*....|....*....|....*....|....*....|.
gi 1063715407 109 ECGICMEMNNMVVLPNCTHSLCIKCYRDW-HGRSESCPFCR 148
Cdd:cd23138     4 NCSFCMQLPERPVTTPCGHNFCLKCFQKWmGQGKKTCGTCR 44

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

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                  ....*....|....*....|....*....|....*....|....*...
gi 1063715407 107 EEECGICMEM---NNMVVLPNCTHSLCIKCYRDWHGRSESCPFCRDSL 151
Cdd:cd23122    11 EDACSICLESfceADPATVTSCKHEYHLQCILEWSQRSKECPMCWQAL 58

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

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                  ....*....|....*....|....*....|....*....|...
gi 1063715407 109 ECGICM---EMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16467     1 ECTICLgeyETGEKLRRLPCSHEFHSECVDRWLKENSSCPICR 43

RING finger, HC subclass, found in muscle-specific RING finger protein 1 (MuRF-1) and similar proteins; MuRF-1, also known as tripartite motif-containing protein 63 (TRIM63), RING finger protein 28 (RNF28), iris RING finger protein, or striated muscle RING zinc finger, is an E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover. It is predominantly fast (type II) fibre-associated in skeletal muscle and can bind to many myofibrillar proteins, including titin, nebulin, the nebulin-related protein NRAP, troponin-I (TnI), troponin-T (TnT), myosin light chain 2 (MLC-2), myotilin, and T-cap. The early and robust upregulation of MuRF-1 is triggered by disuse, denervation, starvation, sepsis, or steroid administration resulting in skeletal muscle atrophy. It also plays a role in maintaining titin M-line integrity. It associates with the periphery of the M-line lattice and may be involved in the regulation of the titin kinase domain. It also participates in muscle stress response pathways and gene expression. MuRF-1 belongs to the C-II subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1063715407 105 EREEECGICMEM--NNMVVLPnCTHSLCIKCYRD--------WHGRSES---------CPFCR 148
Cdd:cd16759     1 EKQLICPICLEMftKPVVILP-CQHNLCRKCANDifqaanpyWQSRGTSmlgsggrfrCPSCR 62

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

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                  ....*....|....*....|....*....|....*....|....
gi 1063715407 110 CGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCRDSLKR 153
Cdd:cd16547     6 CSICHGVLRCPVRLSCSHIFCKKCILQWLKRQETCPCCRKEVKG 49

RING finger, HC subclass, found in Arabidopsis thaliana MND1-interacting protein 1 (MIP1) and similar proteins; This subfamily includes Arabidopsis thaliana MIP1, RING finger protein 4 (RF4) and RING finger protein 298 (RF298). MIP1 interacts with MND1, HOP2 and XRI1. RF4 and RF298 are putative E3 ubiquitin-protein ligase that may mediate E2-dependent protein ubiquitination. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1063715407 106 REEECGICMEMNNMVVLPNCTHS-LCIKCYrDWHGRS--ESCPFCRDSLKR 153
Cdd:cd23128     2 RERECVMCMEEERSVVFLPCAHQvVCSGCN-DLHEKKgmRECPSCRGEIQE 51

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1063715407 109 ECGICMEM--NNMVVLPnCTHSLCIKCYRDWHGRSESCPFC 147
Cdd:pfam13923   1 MCPICMDMlkDPSTTTP-CGHVFCQDCILRALEASNECPLC 40

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

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                  ....*....|....*....|....*....|....*....|..
gi 1063715407 109 ECGICME---MNNMVVLPNCTHSLCIKCYRDWHGRSESCPFC 147
Cdd:cd16468     1 ECVICMAdfvVGDPIRYLPCMHIYHVDCIDDWLMRSFTCPSC 42

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl-b and similar proteins; Cbl-b, also known as Casitas B-lineage lymphoma proto-oncogene b, RING finger protein 56 (RNF56), SH3-binding protein Cbl-b, or signal transduction protein Cbl-b, has been identified as a regulator of antigen-specific, T cell-intrinsic, peripheral immune tolerance, a state also known as clonal anergy. It may inhibit activation of the p85 subunit of phosphoinositide 3-kinase (PI3K), protein kinase C-theta (PKC-theta), and phospholipase C-gamma1 (PLC-gamma1) and negatively regulates T-cell receptor-induced transcription factor nuclear factor kappaB (NF-kappaB) activation. In addition, Cbl-b may target multiple signaling molecules involved in transforming growth factor (TGF)-beta-mediated transactivation pathways. Cbl-b contains a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, is composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain), a proline rich domain, a nuclear localization signal, a C3HC4-type RING-HC finger and an ubiquitin-associated (UBA) domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1063715407 110 CGICMEMNNMVVLPNCTHSLCIKCYRDWH-GRSESCPFCRDSLK 152
Cdd:cd16709    23 CKICAENDKDVKIEPCGHLMCTSCLTAWQeSDGQGCPFCRCEIK 66

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

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gi 1063715407 105 EREEECGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16741    12 EADDICAICQAEFRKPILLICQHVFCEECISLWFNREKTCPLCR 55

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.

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gi 1063715407 108 EECGICM-EMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCRD 149
Cdd:cd16506     1 DTCPICLdEIQNKKTLEKCKHSFCEDCIDRALQVKPVCPVCGV 43

RING finger, HC subclass, found in helicase-like transcription factor (HLTF) and similar proteins; HLTF, also known as DNA-binding protein/plasminogen activator inhibitor 1 regulator, HIP116, RING finger protein 80, SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A member 3, or sucrose nonfermenting protein 2-like 3, is a yeast RAD5 homolog found in mammals. It has both E3 ubiquitin ligase and DNA helicase activities, and plays a pivotal role in the template-switching pathway of DNA damage tolerance. It is involved in Lys-63-linked poly-ubiquitination of proliferating cell nuclear antigen (PCNA) at Lys-164 and in the regulation of DNA damage tolerance. It shows double-stranded DNA translocase activity with 3'-5' polarity, thereby facilitating regression of the replication fork. HLTF contains an N-terminal HIRAN (HIP116 and RAD5 N-terminal) domain, a SWI/SNF helicase domain that is divided into N- and C-terminal parts by an insertion of a C3HC4-type RING-HC finger involved in the poly-ubiquitination of PCNA.

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gi 1063715407 107 EEECGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSE-SCPFCRDSLKR 153
Cdd:cd16509     3 DEECAICLDSLTNPVITPCAHVFCRRCICEVIQREKaKCPMCRAPLSA 50

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.

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gi 1063715407 110 CGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCR 148
Cdd:cd16532     3 CPICQDEFKDPVVLRCKHIFCEDCVSEWFERERTCPLCR 41

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.

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gi 1063715407 110 CGICMEM---NNMVVLPNCTHSLCIKCYRDW-HGRSESCPFCR 148
Cdd:cd16448     1 CVICLEEfeeGDVVRLLPCGHVFHLACILRWlESGNNTCPLCR 43

second RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the second RING-HC finger.

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gi 1063715407 109 ECGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSESCPFCRDSL 151
Cdd:cd16514     3 ECSLCLRLLYEPVTTPCGHTFCRACLERCLDHSPKCPLCRTSL 45

RING finger, HC subclass, found in tripartite motif-containing protein TRIM58 and similar proteins; TRIM58, also known as protein BIA2, is an erythroid E3 ubiquitin-protein ligase induced during late erythropoiesis. It binds and ubiquitinates the intermediate chain of the microtubule motor dynein (DYNC1LI1/DYNC1LI2), stimulating the degradation of the dynein holoprotein complex. It may participate in the erythroblast enucleation process through regulation of nuclear polarization. TRIM58 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.

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gi 1063715407 106 REEECGICMEMNNMVVLPNCTHSLCIKCYRDWHGRSES-------CPFCR 148
Cdd:cd16606     1 EEARCPVCLDFLQEPVSVDCGHSFCLRCISEFCEKSDSaqggvyaCPQCR 50