Transcriptional repressor [Transcription];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652  14 CPLCMEPLEIDDINFFPCTCGYQICRFCWHRIRTDENGLCPACRKPYPEDPAVYKPLSQEELQ---RIKNEKKQKQNERK 90
Cdd:COG5175    17 CPLCIEPMDITDKNFFPCPCGYQICQFCYNNIRQNLNGRCPACRRKYDDENVRYVTLSPEELKmelARKEERKMREKERK 96

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652  91 QKISENRKHLASVRVVQKNLVFVVGLSQRLADPE---VLKRPEYFGKFGKIHKVVINNSTSYAGS--------------- 152
Cdd:COG5175    97 EAEGQNRKHLSNIRVVQKNLVYVIGIPPKVADEEvapVLKRHEYFGQYGKIKKIVVNKKTSSLNStashagvyitystke 176

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652 153 -------------------QASLGTTKYCSYFLKNMQCPKPDCMYLHELGDEAASFTKEEMQAGKHQEYEQKllqelykl 213
Cdd:COG5175   177 daarciaevdgslldgrvlKATYGTTKYCTSYLRNAVCPNPDCMYLHEPGPEKDSLTKDELCNSQHKLHGSE-------- 248

                         250       260       270       280       290       300       310
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1973919652 214 NPNFLQLSTGSVDKNKNKVTPLQSPIDKPSDSlsiGNGDNSQQISNSD------TPSPPPGLSKSNPVIPISSSNHSA 285
Cdd:COG5175   249 VRNKNKKRIHRSTSTARYDTDLLNFTGTPSPA---AMEAQFKHKTSRVfkapdkILFPPLDFTNTQSATPVTLSNSSS 323

Transcriptional repressor [Transcription];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652  14 CPLCMEPLEIDDINFFPCTCGYQICRFCWHRIRTDENGLCPACRKPYPEDPAVYKPLSQEELQ---RIKNEKKQKQNERK 90
Cdd:COG5175    17 CPLCIEPMDITDKNFFPCPCGYQICQFCYNNIRQNLNGRCPACRRKYDDENVRYVTLSPEELKmelARKEERKMREKERK 96

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652  91 QKISENRKHLASVRVVQKNLVFVVGLSQRLADPE---VLKRPEYFGKFGKIHKVVINNSTSYAGS--------------- 152
Cdd:COG5175    97 EAEGQNRKHLSNIRVVQKNLVYVIGIPPKVADEEvapVLKRHEYFGQYGKIKKIVVNKKTSSLNStashagvyitystke 176

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652 153 -------------------QASLGTTKYCSYFLKNMQCPKPDCMYLHELGDEAASFTKEEMQAGKHQEYEQKllqelykl 213
Cdd:COG5175   177 daarciaevdgslldgrvlKATYGTTKYCTSYLRNAVCPNPDCMYLHEPGPEKDSLTKDELCNSQHKLHGSE-------- 248

                         250       260       270       280       290       300       310
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1973919652 214 NPNFLQLSTGSVDKNKNKVTPLQSPIDKPSDSlsiGNGDNSQQISNSD------TPSPPPGLSKSNPVIPISSSNHSA 285
Cdd:COG5175   249 VRNKNKKRIHRSTSTARYDTDLLNFTGTPSPA---AMEAQFKHKTSRVfkapdkILFPPLDFTNTQSATPVTLSNSSS 323

RING/Ubox like zinc-binding domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1973919652  14 CPLCMEPLEIDDINFFPCTCGYQICRFCWHRIRTDENGLCPACRKPY 60
Cdd:pfam14570   1 CPLCDEKLDETDKDFYPCECGYQICRFCYHDILENEGGRCPGCREPY 47

cellulose synthase-like protein

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1973919652    1 MSRSPDAKEDPVECPLC----MEPLEIDDInfFPCTCGYQICRFCWHRIRTDEnGLCPACRKPY 60
Cdd:PLN02248   116 HPQMAGAKGSSCAMPGCdgkvMRDERGEDL--LPCECGFKICRDCYIDAVKSG-GICPGCKEPY 176

Transcriptional repressor [Transcription];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652  14 CPLCMEPLEIDDINFFPCTCGYQICRFCWHRIRTDENGLCPACRKPYPEDPAVYKPLSQEELQ---RIKNEKKQKQNERK 90
Cdd:COG5175    17 CPLCIEPMDITDKNFFPCPCGYQICQFCYNNIRQNLNGRCPACRRKYDDENVRYVTLSPEELKmelARKEERKMREKERK 96

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652  91 QKISENRKHLASVRVVQKNLVFVVGLSQRLADPE---VLKRPEYFGKFGKIHKVVINNSTSYAGS--------------- 152
Cdd:COG5175    97 EAEGQNRKHLSNIRVVQKNLVYVIGIPPKVADEEvapVLKRHEYFGQYGKIKKIVVNKKTSSLNStashagvyitystke 176

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1973919652 153 -------------------QASLGTTKYCSYFLKNMQCPKPDCMYLHELGDEAASFTKEEMQAGKHQEYEQKllqelykl 213
Cdd:COG5175   177 daarciaevdgslldgrvlKATYGTTKYCTSYLRNAVCPNPDCMYLHEPGPEKDSLTKDELCNSQHKLHGSE-------- 248

                         250       260       270       280       290       300       310
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1973919652 214 NPNFLQLSTGSVDKNKNKVTPLQSPIDKPSDSlsiGNGDNSQQISNSD------TPSPPPGLSKSNPVIPISSSNHSA 285
Cdd:COG5175   249 VRNKNKKRIHRSTSTARYDTDLLNFTGTPSPA---AMEAQFKHKTSRVfkapdkILFPPLDFTNTQSATPVTLSNSSS 323

Modified RING finger, HC subclass (C4C4-type), found in CCR4-NOT transcription complex subunit 4 (NOT4) and similar proteins; NOT4, also known as CCR4-associated factor 4, E3 ubiquitin-protein ligase CNOT4, or potential transcriptional repressor NOT4, is a component of the multifunctional CCR4-NOT complex, a global regulator of RNA polymerase II transcription. It associates with polysomes and contributes to the negative regulation of protein synthesis. NOT4 functions as an E3 ubiquitin-protein ligase that interacts with a specific E2, Ubc4/5 in yeast, and the ortholog UbcH5B in humans, and ubiquitylates a wide range of substrates, including ribosome-associated factors. Thus, it plays a role in cotranslational quality control (QC) through ribosome-associated ubiquitination and degradation of aberrant peptides. NOT4 contains a C4C4-type RING finger motif, whose overall folding is similar to that of the C3HC4-type RING-HC finger, a central RNA recognition motif (RRM), and a C-terminal domain predicted to be unstructured.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1973919652  12 VECPLCMEPLEIDDINFFPCTCGYQICRFCWHRIRTDENGLCPACRK 58
Cdd:cd16618     1 PECPLCMEELDITDLNFFPCPCGYQICLFCWHRIREDENGRCPACRK 47

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 1973919652  13 ECPLCMEPLeiddINFFPCTCGYQICRFCWHRIRTDENGLCPAC 56
Cdd:cd16449     2 ECPICLERL----KDPVLLPCGHVFCRECIRRLLESGSIKCPIC 41

BRcat domain found in RING finger protein 216 (RNF216); RNF216, also called Triad domain-containing protein 3 (Triad3A), ubiquitin-conjugating enzyme 7-interacting protein 1, or zinc finger protein inhibiting NF-kappa-B (ZIN), is an RBR-type E3 ubiquitin-protein ligase that interacts with several components of the Toll-like receptor (TLR) signaling pathway and promotes their proteolytic degradation. It negatively regulates the RIG-I RNA sensing pathway through Lys48-linked, ubiquitin-mediated degradation of the tumor necrosis factor (TNF) receptor-associated factor 3 (TRAF3) adapter following RNA virus infection. It also controls ubiquitination and proteasomal degradation of receptor-interacting protein 1 (RIP1), a serine/threonine protein kinase that is critically involved in TNF receptor-1-induced NF-kappa B activation, following disruption of Hsp90 binding. Moreover, RNF216 is involved in inflammatory diseases by strongly inhibiting autophagy in macrophages. It interacts with and ubiquitinates BECN1, a key regulator in autophagy, thereby contributing to BECN1 degradation. It regulates synaptic strength by ubiquitination of Arc, resulting in its rapid proteasomal degradation. It is also a key negative regulator of sustained 2DL4/KIR2DL4 (killer cell Ig-like receptor with two Ig-like domains and a long cytoplasmic domain 4)-mediated NF-kappaB signaling from internalized 2DL4, which functions by promoting ubiquitylation and degradation of endocytosed receptor from early endosomes. Furthermore, RNF216 interacts with human immunodeficiency virus type 1 (HIV-1) virion infectivity factor (Vif) protein, which is essential for the productive infection of primary human CD4 T lymphocytes and macrophages. Mutations in RNF216 may result in Gordon Holmes syndrome, a condition defined by hypogonadotropic hypogonadism and cerebellar ataxia, as well as in autosomal recessive Huntington-like disorder. RNF216 contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of RNF216 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1973919652   9 EDPVECPLCMEPLEIDDINF--FPC---TCGYQICRFC---WHRIRT 47
Cdd:cd20339     2 EGLERCPFCNYAAILDPTEVkvFRCpnpECRKESCRKCkkeWHIPLT 48

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1973919652  13 ECPLCMEPLEiDDINFFPCtcGYQICRFCWHRIRTDENgLCPAC 56
Cdd:pfam13923   1 MCPICMDMLK-DPSTTTPC--GHVFCQDCILRALRAGN-ECPLC 40

RING finger, HC subclass, found in tripartite motif-containing protein 32 (TRIM32) and similar proteins; TRIM32, also known as 72 kDa Tat-interacting protein, zinc finger protein HT2A, or BBS11, is an E3 ubiquitin-protein ligase that promotes degradation of several targets, including actin, PIASgamma, Abl interactor 2, dysbindin, X-linked inhibitor of apoptosis (XIAP), p73 transcription factor, thin filaments and Z-bands during fasting. It plays important roles in neuronal differentiation of neural progenitor cells, as well as in controlling cell fate in skeletal muscle progenitor cells. It reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation. It also functions as a pluripotency-reprogramming roadblock that facilitates cellular transition towards differentiation by modulating the levels of Oct4 and cMyc. Moreover, TRIM32 is an intrinsic influenza A virus (IAV) restriction factor which senses and targets the polymerase basic protein 1 (PB1) for ubiquitination and protein degradation. It also plays a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo, binds specifically to the activation domain of HIV-1 Tat, and can also interact with the HIV-2 and EIAV Tat proteins in vivo. Furthermore, TRIM32 regulates myoblast proliferation by controlling turnover of NDRG2 (N-myc downstream-regulated gene). It negatively regulates tumor suppressor p53 to promote tumorigenesis. It also facilitates degradation of MYCN on spindle poles and induces asymmetric cell division in human neuroblastoma cells. In addition, TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. It also plays a role in regeneration by affecting satellite cell cycle progression via modulation of the SUMO ligase PIASy (PIAS4). Defects in TRIM32 leads to limb-girdle muscular dystrophy type 2H (LGMD2H), sarcotubular myopathies (STM) and Bardet-Biedl syndrome. TRIM32 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. The NHL domain mediates the interaction with Argonaute proteins and consequently allows TRIM32 to modulate the activity of certain miRNAs.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1973919652  12 VECPLCMEPLeiDDINFFP--CTCGYQICRFCWHRIRTDENGL---CPACRK 58
Cdd:cd16587     1 LECPICLESF--DEGQLRPklLHCGHTICEQCLEKLLASLSINgvrCPFCRK 50

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1973919652  14 CPLCME----PLEIDdinffpctCGYQICRFC----WHRirTDENGLCPACRKPYPEDP 64
Cdd:cd16594     8 CPICLDyftdPVTLD--------CGHSFCRACiarcWEE--PETSASCPQCRETCPQRN 56

Modified RING finger, HC subclass (C4C4-type), found in Arabidopsis thaliana cellulose synthase A (CesA) catalytic subunits 1-10, and similar proteins from plants; This subfamily includes plant catalytic subunits of cellulose synthase terminal complexes ("rosettes") required for beta-1,4-glucan microfibril crystallization, a major mechanism of cell wall formation. CesA1, also known as protein RADIALLY SWOLLEN 1 (RSW1), is required during embryogenesis for cell elongation, orientation of cell expansion and complex cell wall formations, such as interdigitated pattern of epidermal pavement cells, stomatal guard cells, and trichomes. It plays a role in lateral roots formation, but seems unnecessary for the development of tip-growing cells such as root hairs. CesA2, also known as Ath-A, is involved in the primary cell wall formation. It forms a homodimer. CesA3, also known as constitutive expression of VSP1 protein 1, isoxaben-resistant protein 1, Ath-B, protein ECTOPIC LIGNIN 1, or protein RADIALLY SWOLLEN 5 (RSW5), is involved in primary cell wall formation, especially in roots. CesA4, also known as protein IRREGULAR XYLEM 5 (IRX5), is involved in the secondary cell wall formation, and required for xylem cell wall thickening. CesA5 may be partially redundant with CesA6. CesA6, also known as AraxCelA, isoxaben-resistant protein 2, protein PROCUSTE 1, or protein QUILL, is involved in primary cell wall formation. Like CesA1, CesA6 is critical for cell expansion. CESA6-dependent cell elongation seems to be independent of gibberellic acid, auxin, and ethylene. CesA6 interacts with and moves along cortical microtubules for the process of cellulose deposition. CesA7, also known as protein FRAGILE FIBER 5, or protein IRREGULAR XYLEM 3 (IRX3), and CesA8, also known as protein IRREGULAR XYLEM 1 (IRX1) or protein LEAF WILTING 2, are both involved in secondary cell wall formation and also required for xylem cell wall thickening. The biological function of CesA9 and CesA10 remain unclear. CesA1, CesA3, and CesA6 form a functional complex essential for primary cell wall cellulose synthesis, while CesA4, CesA7, and CesA8 form a functional complex located in secondary cell wall deposition sites. All family members contain an N-terminal C4C4-type RING-HC finger and a C-terminal glycosyltransferase family A (GT-A) domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1973919652  14 CPLCMEPLEIDDIN--FFPCT-CGYQICRFCWHRIRTDENGLCPACRKP 59
Cdd:cd16617     3 CQICGDEIGLTVNGelFVACNeCGFPVCRPCYEYERKEGNQCCPQCKTR 51

RNA recognition motif;

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|
gi 1973919652  122 DPEVLKR-----PEYFGKFGKIHKVVINNSTSYAGSQASL 156
Cdd:smart00361   1 KDEDFERelkeeEEYFGEVGKINKIYIDDVGYENHKRGNV 40

Double zinc ribbon domain; This domain family is found in bacteria, archaea and eukaryotes, and is approximately 60 amino acids in length. The family is found in association with pfam00156. This entry corresponds to two zinc ribbon motifs. This domain is found at the N-terminus of the ComF operon protein 3.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1973919652  11 PVECPLCMEPLEiddinffpctCGYQICRFCWHRIRTDENGLCPACRKPYPEDP 64
Cdd:pfam18912   7 PPRCPLCGAIVA----------EGGGLCAACWAELPFITEPRCPRCGKPLEEGE 50

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1973919652  10 DPVECPLCMEplEIDDINFFPCTCGYqICRFCWHRIRTdENGLCPACRKP 59
Cdd:pfam13920   1 EDLLCVICLD--RPRNVVLLPCGHLC-LCEECAERLLR-KKKKCPICRQP 46

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM5, TRIM6, TRIM22, TRIM34 and similar proteins; TRIM5, TRIM6, TRIM22, and TRIM34, four 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, 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. TRIM5, also known as RING finger protein 88 (RNF88), is a capsid-specific restriction factor that prevents infection from non-host-adapted retroviruses in a species-specific manner by binding to and destabilizing the retroviral capsid lattice before reverse transcription is completed. Its retroviral restriction activity correlates with the ability to activate TAK1-dependent innate immune signaling. TRIM5 also acts as a pattern recognition receptor that activates innate immune signaling in response to the retroviral capsid lattice. Moreover, TRIM5 plays a role in regulating autophagy through activation of autophagy regulator BECN1 by causing its dissociation from its inhibitors BCL2 and TAB2. It also plays a role in autophagy by acting as a selective autophagy receptor which recognizes and targets HIV-1 capsid protein p24 for autophagic destruction. TRIM6, also known as RING finger protein 89 (RNF89), is an E3-ubiquitin ligase that cooperates with the E2-ubiquitin conjugase UbE2K to catalyze the synthesis of unanchored K48-linked polyubiquitin chains, and further stimulates the interferon-I kappa B kinase epsilon (IKKepsilon) kinase-mediated antiviral response. It also regulates the transcriptional activity of Myc during the maintenance of embryonic stem (ES) cell pluripotency, and may act as a novel regulator for Myc-mediated transcription in ES cells. TRIM22, also known as 50 kDa-stimulated trans-acting factor (Staf-50) or RING finger protein 94 (RNF94), is an E3 ubiquitin-protein ligase that plays an integral role in the host innate immune response to viruses. It has been shown to inhibit the replication of a number of viruses, including HIV-1, hepatitis B, and influenza A. TRIM22 acts as a suppressor of basal HIV-1 long terminal repeat (LTR)-driven transcription by preventing the transcription factor specificity protein 1 (Sp1) binding to the HIV-1 promoter. It also controls FoxO4 activity and cell survival by directing Toll-like receptor 3 (TLR3)-stimulated cells toward type I interferon (IFN) type I gene induction or apoptosis. Moreover, TRIM22 can activate the noncanonical nuclear factor-kappaB (NF-kappaB) pathway by activating I kappa B kinase alpha (IKKalpha). It also regulates nucleotide binding oligomerization domain containing 2 (NOD2)-dependent activation of interferon-beta signaling and nuclear factor-kappaB. TRIM34, also known as interferon-responsive finger protein 1 or RING finger protein 21 (RNF21), may function as antiviral protein that contribute to the defense against retroviral infections.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1973919652   9 EDPVECPLC----MEPLEIDdinffpctCGYQICRFCWHR-----IRTDENGLCPACRKPYP 61
Cdd:cd16591     4 KEEVTCPIClellTEPLSLD--------CGHSFCQACITAnhkesVNQEGESSCPVCRTSYQ 57

RING finger, HC subclass, found in tripartite motif-containing protein 40 (TRIM40) and similar proteins; TRIM40, also known as probable E3 NEDD8-protein ligase or RING finger protein 35 (RNF35), is highly expressed in the gastrointestinal tract including the stomach, small intestine, and large intestine. It enhances neddylation of inhibitor of nuclear factor kappaB kinase subunit gamma (IKKgamma), inhibits the activity of nuclear factor-kappaB (NF-kappaB)-mediated transcription, and thus prevents inflammation-associated carcinogenesis in the gastrointestinal tract. TRIM40 belongs 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, as well as an uncharacterized region positioned C-terminal to the RBCC domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1973919652  14 CPLCMEPLEiddiNFFPCTCGYQICRFCW--HRIRTDENGL--CPACRKPYPE 62
Cdd:cd16583     8 CPICQEPLK----EAVSTDCGHLFCRMCLtqHAKKASASGVfsCPVCRKPCSE 56

RING finger, HC subclass, found in two RING fingers and DRIL [double RING finger linked] 1 (TRIAD1); TRIAD1, also known as ariadne-2 (ARI-2), protein ariadne-2 homolog, Ariadne RBR E3 ubiquitin protein ligase 2 (ARIH2), or UbcM4-interacting protein 48, is an RBR-type E3 ubiquitin-protein ligase that catalyzes the formation of polyubiquitin chains linked via lysine-48, as well as lysine-63 residues. Its auto-ubiquitylation can be catalyzed by the E2 conjugating enzyme UBCH7. TRIAD1 has been implicated in hematopoiesis, specifically in myelopoiesis, as well as in embryogenesis. It functions as a regulator of endosomal transport and is required for the proper function of multivesicular bodies. It also acts as a novel ubiquitination target for proteasome-dependent degradation by murine double minute 2 (MDM2). As a proapoptotic protein, TRIAD1 promotes p53 activation, and inhibits MDM2-mediated p53 ubiquitination and degradation. Furthermore, TRIAD1 can inhibit the ubiquitination and proteasomal degradation of growth factor independence 1 (Gfi1), a transcriptional repressor essential for the function and development of many different hematopoietic lineages. TRIAD1 contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

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gi 1973919652  12 VECPLCMEPLEIDdiNFFPCTCGYQICRFCWH 43
Cdd:cd16773     1 VTCGVCCEDVPKD--ELFSLACGHYFCNDCWK 30

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 1973919652  12 VECPLCMEPLEidDINFfpcTCGYQICRFCWHRIRTdenglCPACRKP 59
Cdd:cd16520     1 ILCPICMERKK--NVVF---LCGHGTCQKCAEKLKK-----CPICRKP 38

RING finger, HC subclass, found in tripartite motif-containing protein TRIM21 and similar proteins; TRIM21, also known as 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A, Ro(SS-A), RING finger protein 81 (RNF81), or Sjoegren syndrome type A antigen (SS-A), is a ubiquitously expressed E3 ubiquitin-protein ligase and a high affinity antibody receptor uniquely expressed in the cytosol of mammalian cells. As a cytosolic Fc receptor, TRIM21 binds the Fc of virus-associated antibodies and targets the complex in the cytosol for proteasomal degradation in a process known as antibody-dependent intracellular neutralization (ADIN), and provides an intracellular immune response to protect host defense against pathogen infection. It shows remarkably broad isotype specificity as it does not only bind IgG, but also IgM and IgA. Moreover, TRIM21 promotes the cytosolic DNA sensor cGAS and the cytosolic RNA sensor RIG-I sensing of viral genomes during infection by antibody-opsonized virus. It stimulates inflammatory signaling and activates innate transcription factors, such as nuclear factor-kappaB (NF-kappaB). TRIM21 also plays an essential role in p62-regulated redox homeostasis, suggesting it may be a viable target for treating pathological conditions resulting from oxidative damage. Furthermore, TRIM21 may have implications for various autoimmune diseases associated with uncontrolled antiviral signaling through the regulation of Nmi-IFI35 complex-mediated inhibition of innate antiviral response. TRIM21 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 1973919652  12 VECPLCMEPLeiddINFFPCTCGYQICRFCWHRIRTDENGLCPACRKPY 60
Cdd:cd16596    10 VTCPICLDPF----VEPVSIECGHSFCQECISQVGKGGGSVCPVCRQRF 54