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 1831511474   9 QWQEVLCCSICNRHFNETFL-PVSLICGHVICRKCAEKPENqtKPCPHD 56
Cdd:cd16781     2 QWTDFLSCPICTQTFDETIRkPISLGCGHTVCKMCLNKLHR--KACPFD 48

Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-1; Roquin-1, also known as RING finger and C3H zinc finger protein 1 (RC3H1), or RING finger protein 198 (RNF198), is a ubiquitously expressed RNA-binding protein essential for degradation of inflammation-related mRNAs and maintenance of immune homeostasis. It is localized in cytoplasmic granules and binds to the 3' untranslated region (3'UTR) of inducible costimulator (Icos) mRNA to post-transcriptionally repress its expression. Roquin-1 interacts with the 3'UTR of tumor necrosis factor receptor superfamily member 4 (TNFRSF4) and tumor-necrosis factor-alpha (TNFalpha), and post-transcriptionally regulates A20 mRNA and modulates the activity of the IKK/NF-kappaB pathway. Moreover, Roquin-1 shares functions with its paralog Roquin-2 in the repression of mRNAs controlling T follicular helper cells and systemic inflammation. Roquin-1 contains an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 ubiquitin-ligase function, a highly conserved ROQ domain required for RNA binding and localization to stress granules, and a CCCH-type zinc finger that is involved in RNA recognition, typically contacting AU-rich elements. In addition, both N- and C-terminal to the ROQ domain are combined to form a HEPN (higher eukaryotes and prokaryotes nucleotide-binding) domain that is highly likely to function as an RNA-binding domain.

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                  ....*....|....*....|....*....|....*....|....*....
gi 1831511474   9 QWQEVLCCSICNRHFNETFL-PVSLICGHVICRKCAEKPENqtKPCPHD 56
Cdd:cd16781     2 QWTDFLSCPICTQTFDETIRkPISLGCGHTVCKMCLNKLHR--KACPFD 48

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)

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gi 1831511474   16 CSICNRHFNETflPVSLICGHVICRKCAEKP-ENQTKPCP 54
Cdd:smart00184   1 CPICLEEYLKD--PVILPCGHTFCRSCIRKWlESGNNTCP 38

Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-1; Roquin-1, also known as RING finger and C3H zinc finger protein 1 (RC3H1), or RING finger protein 198 (RNF198), is a ubiquitously expressed RNA-binding protein essential for degradation of inflammation-related mRNAs and maintenance of immune homeostasis. It is localized in cytoplasmic granules and binds to the 3' untranslated region (3'UTR) of inducible costimulator (Icos) mRNA to post-transcriptionally repress its expression. Roquin-1 interacts with the 3'UTR of tumor necrosis factor receptor superfamily member 4 (TNFRSF4) and tumor-necrosis factor-alpha (TNFalpha), and post-transcriptionally regulates A20 mRNA and modulates the activity of the IKK/NF-kappaB pathway. Moreover, Roquin-1 shares functions with its paralog Roquin-2 in the repression of mRNAs controlling T follicular helper cells and systemic inflammation. Roquin-1 contains an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 ubiquitin-ligase function, a highly conserved ROQ domain required for RNA binding and localization to stress granules, and a CCCH-type zinc finger that is involved in RNA recognition, typically contacting AU-rich elements. In addition, both N- and C-terminal to the ROQ domain are combined to form a HEPN (higher eukaryotes and prokaryotes nucleotide-binding) domain that is highly likely to function as an RNA-binding domain.

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                  ....*....|....*....|....*....|....*....|....*....
gi 1831511474   9 QWQEVLCCSICNRHFNETFL-PVSLICGHVICRKCAEKPENqtKPCPHD 56
Cdd:cd16781     2 QWTDFLSCPICTQTFDETIRkPISLGCGHTVCKMCLNKLHR--KACPFD 48

Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-2; Roquin-2, also known as membrane-associated nucleic acid-binding protein (MNAB), RING finger and CCCH-type zinc finger domain-containing protein 2 (RC3H2), or RING finger protein 164 (RNF164), is an E3 ubiquitin ligase that is localized to the cytoplasm and upon stress, is concentrated in stress granules. It is required for reactive oxygen species (ROS)-induced ubiquitination and degradation of apoptosis signal-regulating kinase 1 (ASK1, also known as MAP3K5). Roquin-2 interacts with the 3'UTR of tumor necrosis factor receptor superfamily member 4 (TNFRSF4) and tumor-necrosis factor-alpha (TNFalpha), and modulates immune responses. Moreover, Roquin-2 shares functions with its paralog Roquin-1 in the repression of mRNAs controlling T follicular helper cells and systemic inflammation. Roquin-2 contains an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 ubiquitin-ligase function, a highly conserved ROQ domain required for RNA binding and localization to stress granules, a coiled-coil (CC1), and a CCCH-type zinc finger that is involved in RNA recognition.

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                  ....*....|....*....|....*....|....*....|....*....
gi 1831511474   9 QWQEVLCCSICNRHFNE-TFLPVSLICGHVICRKCAEKPENqtKPCPHD 56
Cdd:cd16782     1 QWTEFLSCPICYNEFDEnVHKPISLGCSHTVCKTCLNKLHR--KACPFD 47

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 1831511474  11 QEVLCCSICNRHFNEtflPVSLICGHVICRKC----AEKPENQTKPCP 54
Cdd:cd16609     1 EEELTCSICLGLYQD---PVTLPCQHSFCRACiedhWRQKDEGSFSCP 45

RING-type zinc-finger; This zinc-finger is a typical RING-type of plant ubiquitin ligases.

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                  ....*....|....*....|....*....|....*....|..
gi 1831511474  16 CSICNRHFNEtflPVsLICGHVICRKCAEKP---ENQTKPCP 54
Cdd:pfam13445   1 CPICLELFTD---PV-LPCGHTFCRECLEEMsqkKGGKFKCP 38

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.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1831511474  14 LCCSICNRHFNEtflPVSLICGHVICRKCAEKP----ENQTKPCPH 55
Cdd:cd16597     6 LTCSICLELFKD---PVTLPCGHNFCGVCIEKTwdsqHGSEYSCPQ 48

Modified RING finger, HC subclass (C3HC3D-type), found in Caenorhabditis elegans putative GTP-binding protein trim-23 homolog (arc-1) and similar proteins; arc-1, also called RING-type E3 ubiquitin transferase arc-1, is an E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. arc-1 contains a modified C3HC3D-type RING-HC finger.

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gi 1831511474  16 CSICNRHFNETflpVSLI-------CGHVICRKCAEKPENQTKP---CPHD 56
Cdd:cd23124     4 CGICQQEYSAD---DPLLiprilteCGHTICTNCAGTILGQSSGsifCPFD 51

RING finger, HC subclass, found in RING finger proteins RNF113A, RNF113B, and similar proteins; RNF113A, also known as zinc finger protein 183 (ZNF183), is an E3 ubiquitin-protein ligase that physically interacts with the E2 protein, UBE2U. A nonsense mutation in RNF113A is associated with an X-linked trichothiodystrophy (TTD). Its yeast ortholog Cwc24p is predicted to have a spliceosome function and acts in a complex with Cef1p to participate in pre-U3 snoRNA splicing, indirectly affecting pre-rRNA processing. It is also important for the U2 snRNP binding to primary transcripts and co-migrates with spliceosomes. Moreover, the ortholog of RNF113A in fruit flies may also act as a spliceosome and is hypothesized to be involved in splicing, namely within the central nervous system. The ortholog in Caenorhabditis elegans is involved in DNA repair of inter-strand crosslinks. RNF113B, also known as zinc finger protein 183-like 1, shows high sequence similarity with RNF113A. Both RNF113A and RNF113B contain a CCCH-type zinc finger, which is commonly found in RNA-binding proteins involved in splicing, and a C3HC4-type RING-HC finger, which is frequently found in E3 ubiquitin ligases.

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                  ....*....|....*....|....*....|....*....|
gi 1831511474  15 CCSICNRHFNEtflPVSLICGHVICRKCAEKPENQTKPCP 54
Cdd:cd16539     7 ACFICRKPFKN---PVVTKCGHYFCEKCALKHYRKSKKCF 43

RING finger, HC subclass, found in tripartite motif-containing proteins, TRIM7, TRIM11 and TRIM27, and similar proteins; TRIM7, TRIM11 and TRIM27, closely related tripartite motif-containing proteins, belong 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, Bbox2, and a coiled coil region, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) by mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. TRIM11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM27, also known as RING finger protein 76 (RNF76), RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. In addition, it inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. TRIM27 promotes a non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. TRIM27 also forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is a component of an estrogen receptor 1 (ESR1) regulatory complex that is involved in estrogen receptor-mediated transcription in MCF-7 cells.

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gi 1831511474  11 QEVLCCSICNRHFNEtflPVSLICGHVICR----KCAEKPENQTkPCPH 55
Cdd:cd16594     3 QEELTCPICLDYFTD---PVTLDCGHSFCRaciaRCWEEPETSA-SCPQ 47

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 1831511474  15 CCSICNRHFNEtflPVSLICGHVICRKCAEKPENQTKPCP 54
Cdd:cd16561     4 ECSICLEDLND---PVKLPCDHVFCEECIRQWLPGQMSCP 40

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 1831511474  16 CSICNRHFNEtflPVSLICGHVICRKCAEKPENQTKPCP 54
Cdd:cd16741    17 CAICQAEFRK---PILLICQHVFCEECISLWFNREKTCP 52

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 1831511474  14 LCCSICNRHFNETflpVSLICGHVICRKCAEKPENQTKPCP 54
Cdd:cd16535     2 LQCSICSELFIEA---VTLNCSHSFCSYCITEWMKRKKECP 39

zinc-RING finger domain;

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gi 1831511474  16 CSICNRHFNETFLPVSLICGHVICRKCAeKPENQTKPCP 54
Cdd:pfam14634   2 CNKCFKELSKTRPFYLTSCGHIFCEECL-TRLLQERQCP 39

RING finger, HC subclass, found in Saccharomyces cerevisiae increased recombination centers protein 20 (IRC20) and similar proteins; IRC20 is an uncharacterized ATP-dependent helicase that is probably involved in a pathway contributing to genomic integrity. IRC20 contains a typical C3HC4-type RING-HC finger.

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gi 1831511474  14 LCCSICnrhFNETFLPVSLICGHVICRKCAEKPENQTKPCP 54
Cdd:cd23135     4 LSCSIC---FSEIRSGAILKCGHFFCLSCIASWLREKSTCP 41

RING finger, HC subclass, found in tripartite motif-containing protein 38 (TRIM38) and similar proteins; TRIM38, also known as RING finger protein 15 (RNF15) or zinc finger protein RoRet, is an E3 ubiquitin-protein ligase that promotes K63- and K48-linked ubiquitination of cellular proteins and also catalyzes self-ubiquitination. It negatively regulates Tumor necrosis factor alpha (TNF-alpha)- and interleukin-1beta-triggered Nuclear factor-kappaB (NF-kappaB) activation by mediating lysosomal-dependent degradation of transforming growth factor beta (TGFbeta)-activated kinase 1 (TAK1)-binding protein (TAB)2/3, two critical components of the TAK1 kinase complex. It also inhibits TLR3/4-mediated activation of NF-kappaB and interferon regulatory factor 3 (IRF3) by mediating ubiquitin-proteasomal degradation of TNF receptor-associated factor 6 (Traf6) and NAK-associated protein 1 (Nap1), respectively. Moreover, TRIM38 negatively regulates TLR3-mediated interferon beta (IFN-beta) signaling by targeting ubiquitin-proteasomal degradation of TIR domain-containing adaptor inducing IFN-beta (TRIF). It functions as a valid target for autoantibodies in primary Sjogren's Syndrome. TRIM38 belongs 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, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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gi 1831511474  12 EVLCCSICNRHFNEtflPVSLICGHVICRKC---------AEKPENQTKPCPH 55
Cdd:cd16600     4 EEATCSICLQLMTE---PVSINCGHSYCKRCivsflenqsQLEPGLETFSCPQ 53

RING finger, HC subclass, found in tripartite motif-containing protein 62 (TRIM62) and similar proteins; TRIM62, also known as Ductal Epithelium Associated Ring Chromosome 1 (DEAR1), is a cytoplasmic E3 ubiquitin-protein ligase that was identified as a dominant regulator of acinar morphogenesis in the mammary gland. It is implicated in the inflammatory response of immune cells by regulating the Toll-like receptor 4 (TLR4) signaling pathway, leading to increased activity of the activator protein 1 (AP-1) transcription factor in primary macrophages. It is also involved in muscular protein homeostasis, especially during inflammation-induced atrophy, and may play a role in the pathogenesis of ICU-acquired weakness (ICUAW) by activating and maintaining inflammation in myocytes. Moreover, TRIM62 facilitates K27-linked poly-ubiquitination of CARD9 and also regulates CARD9-mediated anti-fungal immunity and intestinal inflammation. It also functions as a chromosome 1p35 tumor suppressor and negatively regulates transforming growth factor beta (TGFbeta)-driven epithelial-mesenchymal transition (EMT) by binding to and promoting the ubiquitination of SMAD3, a major effector of TGFbeta-mediated EMT. TRIM62 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 1831511474  14 LCCSICNRHFNEtflPVSLICGHVICRKC 42
Cdd:cd16608     7 LLCSICLSIYQD---PVSLGCEHYFCRQC 32

RING finger, HC subclass, found in BRCA1-associated RING domain protein 1 (BARD-1) and similar proteins; BARD-1 is a critical factor in BRCA1-mediated tumor suppression and may also serve as a target for tumorigenic lesions in some human cancers. It associates with BRCA1 (breast cancer-1) to form a heterodimeric BRCA1/BARD1 complex that is responsible for maintaining genomic stability through nuclear functions involving DNA damage signaling and repair, transcriptional regulation, and cell cycle control. The BRCA1/BARD1 complex catalyzes autoubiquitination of BRCA1 and trans ubiquitination of other protein substrates. Its E3 ligase activity is dramatically reduced in the presence of UBX domain protein 1 (UBXN1). BARD-1 contains an C3HC4-type RING-HC finger that binds BRCA1 at its N-terminus and three tandem ankyrin repeats and tandem BRCT repeat domains at its C-terminus. The BRCT repeats bind CstF-50 (cleavage stimulation factor) to modulate mRNA processing and RNAP II stability in response to DNA damage.

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gi 1831511474   8 GQWQEVLCCSICNRHFNEtflPVSL-ICGHVICRKCAekPENQTKPCP 54
Cdd:cd16496    10 DELENLLRCSRCASILKE---PVTLgGCEHVFCRSCV--GDRLGNGCP 52

RING finger, HC subclass, found in mind bomb MIB1, MIB2, RGLG1, RGLG2, and similar proteins; MIBs are large, multi-domain E3 ubiquitin-protein ligases that promote ubiquitination of the cytoplasmic tails of Notch ligands. They are also responsible for TBK1 K63-linked ubiquitination and activation, promoting interferon production and controlling antiviral immunity. Moreover, MIBs selectively control responses to cytosolic RNA and regulate type I interferon transcription. Both MIB1 and MIB2 have similar domain architectures, which consist of two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region, where MIB1 and MIB2 contain three and two C3HC4-type RING-HC fingers, respectively. This model corresponds to the third RING-HC finger of MIB1, as well as the second RING-HC finger of MIB2. In addition to MIB1 and MIB2, the RING-HC fingers of RING domain ligase RGLG1, RGLG2 and similar proteins from plant are also included in this model. RGLG1 is a ubiquitously expressed E3 ubiquitin-protein ligase that interacts with UBC13 and, together with UBC13, catalyzes the formation of K63-linked polyubiquitin chains, which is involved in DNA damage repair. RGLG1 mediates the formation of canonical, K48-linked polyubiquitin chains that target proteins for degradation. It also regulates apical dominance by acting on the auxin transport proteins abundance. RGLG1 has overlapping functions with its closest sequelog, RGLG2. They both function as RING E3 ligases that interact with ethylene response factor 53 (ERF53) in the nucleus and negatively regulate the plant drought stress response. All RGLG proteins contain a Von Willebrand factor type A (vWA) domain and a C3HC4-type RING-HC finger.

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gi 1831511474  15 CCSIC-NRHFNETFLpvsliCGHVICRKCAEKpenqTKPCP 54
Cdd:cd16520     2 LCPICmERKKNVVFL-----CGHGTCQKCAEK----LKKCP 33

RING finger, HC subclass, found in Arabidopsis thaliana protein KEEP ON GOING (KEG) and similar proteins; KEG, also called RING-type E3 ubiquitin transferase KEG, is a RING E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. It is essential for Arabidopsis growth and development. It acts as a negative regulator of abscisic acid signaling. It is required for ABSCISIC ACID-INSENSITIVE5 (ABI5) degradation, by mediating its ubiquitination. Together with EDR1, KEG may regulate endocytic trafficking and/or the formation of signaling complexes on trans-Golgi network (TGN)/ early endosome (EE) vesicles during stress responses. KEG is a multidomain protein that includes a C3HC4-type RING-HC finger, a kinase domain, ankyrin repeats, and 12 HERC2-like (for HECT and RCC1-like) repeats.

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gi 1831511474  13 VLCCSICNRHFNET-FLPVSLICGHVICRKCAEKPE----NQTKPCP 54
Cdd:cd23140     1 VPECSVCSEGYNEDeRVPLLLQCGHTFCKDCLSQMFirctDLTLKCP 47

Protein present in Fab1, YOTB, Vac1, and EEA1; The FYVE zinc finger is named after four proteins where it was first found: Fab1, YOTB/ZK632.12, Vac1, and EEA1. The FYVE finger has been shown to bind two Zn2+ ions. The FYVE finger has eight potential zinc coordinating cysteine positions. The FYVE finger is structurally related to the PHD finger and the RING finger. Many members of this family also include two histidines in a motif R+HHC+XCG, where + represents a charged residue and X any residue. The FYVE finger functions in the membrane recruitment of cytosolic proteins by binding to phosphatidylinositol 3-phosphate (PI3P), which is prominent on endosomes. The R+HHC+XCG motif is critical for PI3P binding.

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                   ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1831511474    9 QWQ---EVLCCSICNRHFNetflpvsLI--------CGHVICRKCAEK-----PENQTKPC 53
Cdd:smart00064   3 HWIpdeEVSNCMGCGKEFN-------LTkrrhhcrnCGRIFCSKCSSKkaplpKLGIERPV 56