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.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEHavaatssaSTSSARCPQCRLEFQPRDVTPL 311
Cdd:cd16527    1 RKCSLCLEErRHPTATPCGHLFCWSCITEW--------CNEKPECPLCREPFQPQRLVPL 52

RING finger, HC subclass, found in peroxin-10 (PEX10) and similar proteins; PEX10, also known as peroxisome biogenesis factor 10, peroxisomal biogenesis factor 10, peroxisome assembly protein 10, or RING finger protein 69 (RNF69), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It plays an essential role in peroxisome assembly, import of target substrates, and recycling or degradation of protein complexes and amino acids. It is an essential component of the spinal locomotor circuit, and thus its mutations may be involved in peroxisomal biogenesis disorders (PBD). Mutations in human PEX10 also result in autosomal recessive ataxia. Moreover, PEX10 functions as an E3-ubiquitin ligase with an E2, UBCH5C. It mono- or poly-ubiquitinates PEX5, a key player in peroxisomal matrix protein import, in a UBC4-dependent manner, to control PEX5 receptor recycling or degradation. It also links the E2 ubiquitin conjugating enzyme PEX4 to the protein import machinery of the peroxisome.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEHavaatssaSTSSARCPQCRLEFQPRDVTPL 311
Cdd:cd16527    1 RKCSLCLEErRHPTATPCGHLFCWSCITEW--------CNEKPECPLCREPFQPQRLVPL 52

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 392894943   255 CSICLEN--KNPSALFCGHLFCWTCIQEHavaatssASTSSARCPQC 299
Cdd:smart00184   1 CPICLEEylKDPVILPCGHTFCRSCIRKW-------LESGNNTCPIC 40

E3 ubiquitin-protein ligase RMA2; Provisional

                         10        20
                 ....*....|....*....|....*....
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQE 280
Cdd:PLN03208  19 FDCNICLDQvRDPVVTLCGHLFCWPCIHK 47

RING finger, HC subclass, found in peroxin-10 (PEX10) and similar proteins; PEX10, also known as peroxisome biogenesis factor 10, peroxisomal biogenesis factor 10, peroxisome assembly protein 10, or RING finger protein 69 (RNF69), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It plays an essential role in peroxisome assembly, import of target substrates, and recycling or degradation of protein complexes and amino acids. It is an essential component of the spinal locomotor circuit, and thus its mutations may be involved in peroxisomal biogenesis disorders (PBD). Mutations in human PEX10 also result in autosomal recessive ataxia. Moreover, PEX10 functions as an E3-ubiquitin ligase with an E2, UBCH5C. It mono- or poly-ubiquitinates PEX5, a key player in peroxisomal matrix protein import, in a UBC4-dependent manner, to control PEX5 receptor recycling or degradation. It also links the E2 ubiquitin conjugating enzyme PEX4 to the protein import machinery of the peroxisome.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEHavaatssaSTSSARCPQCRLEFQPRDVTPL 311
Cdd:cd16527    1 RKCSLCLEErRHPTATPCGHLFCWSCITEW--------CNEKPECPLCREPFQPQRLVPL 52

RING finger, HC subclass, found in tripartite motif-containing protein 69 (TRIM69) and similar proteins; TRIM69, also known as RFP-like domain-containing protein trimless or RING finger protein 36 (RNF36), is a testis E3 ubiquitin-protein ligase that plays a specific role in apoptosis and may also play an important role in germ cell homeostasis during spermatogenesis. TRIM69 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLE-NKNPSALFCGHLFCWTCIQEHAVAATSSAStssarCPQCRLEFQPRDVTP 310
Cdd:cd16611    7 CPLCLDfFRDPVMLSCGHNFCQSCITGFWELQAEDTT-----CPECRELCQYRNLTP 58

RING finger, HC subclass, found in breast cancer type 1 susceptibility protein (BRCA1) and similar proteins; BRCA1, also known as RING finger protein 53 (RNF53), is a RING finger protein encoded by the tumor suppressor gene BRCA1 that regulates all DNA double-strand break (DSB) repair pathways. BRCA1 is frequently mutated in patients with hereditary breast and ovarian cancer (HBOC). Its mutation is also associated with an increased risk of pancreatic, stomach, laryngeal, fallopian tube, and prostate cancer. It plays an important role in the DNA damage response signaling and has been implicated in various cellular processes such as cell cycle regulation, transcriptional regulation, chromatin remodeling, DNA DSBs, and apoptosis. BRCA1 contains an N-terminal C3HC4-type RING-HC finger, and two BRCT (BRCA1 C-terminus domain) repeats at the C-terminus.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 392894943 247 SLFHPTFQCSICLE-NKNPSALFCGHLFCWTCIQEhavaaTSSASTSSARCPQCRLEFQPRDVTP 310
Cdd:cd16498   11 SAMQKNLECPICLElLKEPVSTKCDHQFCRFCILK-----LLQKKKKPAPCPLCKKSVTKRSLQE 70

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 392894943   255 CSICLEN--KNPSALFCGHLFCWTCIQEHavaatssASTSSARCPQC 299
Cdd:smart00184   1 CPICLEEylKDPVILPCGHTFCRSCIRKW-------LESGNNTCPIC 40

RING finger, HC subclass, found in Arabidopsis thaliana RING membrane-anchor proteins (AtRMAs) and similar proteins; AtRMAs, including AtRma1, AtRma2, and AtRma3, are endoplasmic reticulum (ER)-localized Arabidopsis homologs of human outer membrane of the ER-anchor E3 ubiquitin-protein ligase, RING finger protein 5 (RNF5). AtRMAs possess E3 ubiquitin ligase activity, and may play a role in the growth and development of Arabidopsis. The AtRMA1 and AtRMA3 genes are predominantly expressed in major tissues, such as cotyledons, leaves, shoot-root junction, roots, and anthers, while AtRMA2 expression is restricted to the root tips and leaf hydathodes. AtRma1 probably functions with the Ubc4/5 subfamily of E2. AtRma2 is likely involved in the cellular regulation of ABP1 expression levels through interacting with auxin binding protein 1 (ABP1). AtRMA proteins contain an N-terminal C3HC4-type RING-HC finger and a trans-membrane-anchoring domain in their extreme C-terminal region.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEhavaaTSSASTSSARCPQCR 300
Cdd:cd16745    1 FECNICLDLaQDPVVTLCGHLFCWPCLHK-----WLRRQSSQPECPVCK 44

RING finger, HC subclass, found in RING finger protein RNF5, RNF185 and similar proteins; RNF5 and RNF185 are E3 ubiquitin-protein ligases that are anchored to the outer membrane of the endoplasmic reticulum (ER). RNF5 acts at early stages of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) biosynthesis, and functions as a target for therapeutic modalities to antagonize mutant CFTR proteins in CF patients carrying the F508del allele. RNF185 controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical endoplasmic reticulum-associated degradation (ERAD) model substrates. Moreover, both RNF5 and RNF185 play important roles in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. Arabidopsis thaliana RING membrane-anchor proteins (AtRMAs) are also included in this family. They possess E3 ubiquitin-protein ligase activity and may play a role in the growth and development of Arabidopsis. All members of this family contain a C3HC4-type RING-HC finger.

                         10        20
                 ....*....|....*....|....*....
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQE 280
Cdd:cd16534    1 FECNICLDTaSDPVVTMCGHLFCWPCLYQ 29

Ring finger domain;

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                  ....*....|....*....|....*....|....*....|....*....|..
gi 392894943  253 FQCSICLEN----KNPSALFCGHLFCWTCIQEHavaatssaSTSSARCPQCR 300
Cdd:pfam13639   1 DECPICLEEfeegDKVVVLPCGHHFHRECLDKW--------LRSSNTCPLCR 44

RING finger, HC subclass, found in RING finger protein 185 (RNF185) and similar proteins; RNF185 is an E3 ubiquitin-protein ligase of endoplasmic reticulum-associated degradation (ERAD) that targets cystic fibrosis transmembrane conductance regulator (CFTR). It controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical ERAD model substrates. It also negatively regulates osteogenic differentiation by targeting dishevelled2 (Dvl2), a key mediator of the Wnt signaling pathway, for degradation. Moreover, RNF185 regulates selective mitochondrial autophagy through interaction with the Bcl-2 family protein BNIP1. It also plays an important role in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. RNF185 contains a C3HC4-type RING-HC finger.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEHAVAATSSAStssarCPQCRLEFQPRDVTPL 311
Cdd:cd16744    1 FECNICLDTaKDAVVSLCGHLFCWPCLHQWLETRPNRQV-----CPVCKAGISRDKVIPL 55

RING finger, HC subclass, found in tripartite motif-containing protein TRIM17 and similar proteins; TRIM17, also known as RING finger protein 16 (RNF16) or testis RING finger protein (Terf), is a crucial E3 ubiquitin ligase that is necessary and sufficient for neuronal apoptosis and contributes to Mcl-1 ubiquitination in cerebellar granule neurons (CGNs). It interacts in a SUMO-dependent manner with nuclear factor of activated T cell NFATc3 transcription factor, and thus inhibits the activity of NFATc3 by preventing its nuclear localization. In contrast, it binds to and inhibits NFATc4 transcription factor in a SUMO-independent manner. Moreover, TRIM17 stimulates degradation of kinetochore protein ZW10 interacting protein (ZWINT), a known component of the kinetochore complex required for the mitotic spindle checkpoint, and negatively regulates cell proliferation. TRIM17 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 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQEHAVAATSSASTSSAR----CPQCRLEFQPRDVTP 310
Cdd:cd16595    8 CSICLDYfTDPVMTTCGHNFCRACIQLSWEKARGKKGRRKQKgsfpCPECREMSPQRNLRP 68

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

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                  ....*....|....*....|....*....|....*....|...
gi 392894943  255 CSICLENKNPSALFCGHLFCWTCIQEhavaaTSSASTSSARCP 297
Cdd:pfam13445   1 CPICLELFTDPVLPCGHTFCRECLEE-----MSQKKGGKFKCP 38

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 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEHAVAATSSAstssarCPQCRLEF 303
Cdd:cd16608    7 LLCSICLSIyQDPVSLGCEHYFCRQCITEHWSRSEHRD------CPECRRTF 52

RING finger, HC subclass, found in Arabidopsis thaliana protein BENZOIC ACID HYPERSENSITIVE 1 (BAH1) and similar proteins; This subfamily includes Arabidopsis thaliana BAH1 and BAH1-like. BAH1, also known as protein NITROGEN LIMITATION ADAPTATION (NLA), or RING-type E3 ubiquitin transferase BAH1, acts as an E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. It plays a role in salicylic acid-mediated negative feedback regulation of salicylic acid (SA) accumulation. It may be involved in the overall regulation of SA, benzoic acid and phenylpropanoid biosynthesis. It controls the adaptability to nitrogen limitation by channeling the phenylpropanoid metabolic flux to the induced anthocyanin synthesis. BAH1-like, also known as RING finger protein 178, or RING-type E3 ubiquitin transferase BAH1-like, is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

                         10        20
                 ....*....|....*....|....
gi 392894943 255 CSICLENK-NPSALFCGHLFCWTC 277
Cdd:cd23127   11 CSICLDTVfDPVALGCGHLFCNSC 34

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 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIqehavAATSSASTSSARCPQCRLEFQPRDVTP 310
Cdd:cd16594    8 CPICLDYfTDPVTLDCGHSFCRACI-----ARCWEEPETSASCPQCRETCPQRNLRP 59

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM41, TRIM52 and similar proteins; TRIM41 and TRIM52, two closely related tripartite motif-containing proteins, have dramatically expanded RING domains compared with the rest of the TRIM family proteins. TRIM41 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. In contrast, TRIM52 lacks the putative viral recognition SPRY/B30.2 domain, and thus has been classified to the C-V subclass of the TRIM family that contains only RBCC domains. TRIM41, also known as RING finger-interacting protein with C kinase (RINCK), is an E3 ubiquitin-protein ligase that promotes the ubiquitination of protein kinase C (PKC) isozymes in cells. It specifically recognizes the C1 domain of PKC isozymes. It controls the amplitude of PKC signaling by controlling the amount of PKC in the cell. TRIM52, also known as RING finger protein 102 (RNF102), is encoded by a novel, noncanonical antiviral TRIM52 gene in primate genomes with unique specificity determined by the rapidly evolving RING domain.

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                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQEhavaatssasTSSARCPQCRLEFQPRDVTP 310
Cdd:cd16602    6 CAICLDYfKDPVSIGCGHNFCRVCVTQ----------LWGFTCPQCRKSFPRRSFRP 52

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.

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                 ....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQEHAVAATSSASTSsarCPQCR 300
Cdd:cd16583    8 CPICQEPlKEAVSTDCGHLFCRMCLTQHAKKASASGVFS---CPVCR 51

RING finger, HC subclass, found in RING finger protein 39 (RNF39) and similar proteins; RNF39, also called protein HZFw, may play a role in prolonged long term-potentiation (LTP) maintenance. It is involved in the etiology of Behcet's disease (BD). It may also be involved in HIV-1 replication. RNF39 acts as an E3 ubiquitin ligase that inhibits retinoic acid-inducible gene-I (RIG-I)-like receptor (RLR) pathways by mediating K48-linked ubiquitination and proteasomal degradation of DDX3X (DEAD-box RNA helicase 3, X-linked). RNF39 contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQEH-AVAATSSASTSSARCPQCRLEF 303
Cdd:cd16592    7 CPICLGYfKDPVILDCEHSFCRACIARHwGQEAMEGNGAEGVFCPQCGEPC 57

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQehAVAATSSASTSSARCPQCRLEFQPRDVTP 310
Cdd:cd16591    9 CPICLELlTEPLSLDCGHSFCQACIT--ANHKESVNQEGESSCPVCRTSYQPENLRP 63

Modified RING finger found in peroxin-12 (PEX12) and similar proteins; PEX12, also known as peroxisome assembly protein 12 or peroxisome assembly factor 3 (PAF-3), is a RING finger domain-containing integral membrane peroxin required for protein import into peroxisomes. Mutations in human PEX12 result in the peroxisome deficiency Zellweger syndrome of complementation group III (CG-III), a lethal neurological disorder. PEX12 also functions as an E3-ubiquitin ligase that facilitates the PEX4-dependent monoubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation. PEX12 contains a modified RING finger that lacks the third, fourth, and eighth zinc-binding residues of the consensus RING finger motif, suggesting PEX12 may only bind one zinc ion.

                         10        20
                 ....*....|....*....|....*....
gi 392894943 255 CSICLEN-KNPSALFC-GHLFCWTCIQEH 281
Cdd:cd16451    3 CPLCRKKrTNPTALATsGYVFCYPCIYRY 31

RING finger, HC subclass, found in tripartite motif-containing protein 10 (TRIM10) and similar proteins; TRIM10, also known as B30-RING finger protein (RFB30), RING finger protein 9 (RNF9), or hematopoietic RING finger 1 (HERF1), is a novel hematopoiesis-specific RING finger protein required for terminal differentiation of erythroid cells. TRIM10 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQEHAVAATSSASTSSArCPQCRLEFQP 305
Cdd:cd16593    8 CPICQGTlREPVTIDCGHNFCRACLTRYCEIPGPDLEEPPT-CPLCKEPFRP 58

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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 392894943 255 CSICLE-NKNPSALFCGHLFCWTCIQEHAV-AATSSASTSSARCPQCRLEF 303
Cdd:cd16600    8 CSICLQlMTEPVSINCGHSYCKRCIVSFLEnQSQLEPGLETFSCPQCRAPF 58

RING finger, HC subclass, found in Arabidopsis thaliana proteolysis 1 protein (PRT1) and similar proteins; PRT1, also called RING-type E3 ubiquitin transferase PRT1, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of target proteins. It functions in the N-end rule pathway of protein degradation, where it specifically recognizes and ubiquitinates proteins with an N-terminal bulky aromatic amino acid (Phe). It does not act on aliphatic hydrophobic and basic N-terminal residues (Arg or Leu) containing proteins. PRT1 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEhavaatSSASTSSARCPQCRLEF 303
Cdd:cd23132    3 FLCCICLDLlYKPVVLECGHVFCFWCVHR------CMNGYDESHCPLCRRPY 48

RING finger, HC subclass, found in RING finger protein 222 (RNF222) and similar proteins; RNF222 is an uncharacterized C3HC4-type RING-HC finger-containing protein. It may function as an E3 ubiquitin-protein ligase.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 392894943 255 CSICLEN--KNPSALFCGHLFCWTCIqehavaaTSSASTSSARCPQCR 300
Cdd:cd16564    3 CPVCYEDfdDAPRILSCGHSFCEDCL-------VKQLVSMTISCPICR 43

DNA repair protein rad18; All proteins in this family for which functions are known are involved in nucleotide excision repair.This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 392894943  249 FHPTFQCSICLEN-KNPSALFCGHLFCWTCIQEHavaatssaSTSSARCPQCRLEFQ 304
Cdd:TIGR00599  23 LDTSLRCHICKDFfDVPVLTSCSHTFCSLCIRRC--------LSNQPKCPLCRAEDQ 71

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 392894943 254 QCSICLEN-KNPSALFCGHLFCWT-CIQehavaATSSASTSSARCPQCRLE 302
Cdd:cd16524    7 TCPICLDRyRRPKLLPCQHTFCLSpCLE-----GLVDYVTRKLKCPECRAE 52

RING finger, H2 subclass, found in Arabidopsis thaliana protein WAV3 homolog 2 (WAVH2) and similar proteins; WAVH2, also known as RING-type E3 ubiquitin transferase WAVH2, is a probable E3 ubiquitin-protein ligase involved in the regulation of root growth. It acts as a positive regulator of root gravitropism. WAVH2 contains a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 392894943 254 QCSICLENKNPSALF------CGHLFCWTCIQEHavaatssASTSSARCPQCR 300
Cdd:cd23114    6 ECSICLETMKPGSGHaiftaeCSHSFHFECIAGN-------VRHGNLRCPVCR 51

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLE-NKNPSALFCGHLFCWTCIqEHAVAATSSASTSSARCPQCR 300
Cdd:cd16581    5 CSICYNiFDDPKILPCSHTFCKNCL-EKLLAASGYYLLASLKCPTCR 50

RING finger, HC subclass, found in RING finger protein 166 (RNF166) and similar proteins; RNF166 is encoded by the gene RNF166 targeted by thyroid hormone receptor alpha1 (TRalpha1), which is important in brain development. It plays an important role in RNA virus-induced interferon-beta production by enhancing the ubiquitination of TRAF3 and TRAF6. RNF166, together with three closely related proteins: RNF114, RNF125 and RNF138, forms a novel family of ubiquitin ligases with a C3HC4-type RING-HC finger, a C2HC-, and two C2H2-type zinc fingers, as well as a ubiquitin interacting motif (UIM).

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 392894943 253 FQCSICLE--NKNPSALFCGHLFCWTCIQEhavaatsSASTSSARCPQCRLEF 303
Cdd:cd16549    2 FSCPICLEvyHKPVVITSCGHTFCGECLQP-------CLQVASPLCPLCRMPF 47

RING finger, HC subclass, found in RING finger protein 146 (RNF146) and similar proteins; RNF146, also known as dactylidin, or iduna, is a cytoplasmic E3 ubiquitin-protein ligase that is responsible for PARylation-dependent ubiquitination (PARdU). It displays neuroprotective property due to its inhibition of Parthanatos, a PAR dependent cell death, via binding with Poly(ADP-ribose) (PAR). It also modulates PAR polymerase-1 (PARP-1)-mediated oxidative cell injury in cardiac myocytes. Moreover, RNF146 mediates tankyrase-dependent degradation of axin, thereby positively regulating Wnt signaling. It also facilitates DNA repair and protects against cell death induced by DNA damaging agents or gamma-irradiation by translocating to the nucleus after cellular injury and promoting the ubiquitination and degradation of various nuclear proteins involved in DNA damage repair. Furthermore, RNF146 is implicated in neurodegenerative disease and cancer development. It regulates the development and progression of non-small cell lung cancer (NSCLC) by enhancing cell growth, invasion, and survival. RNF146 contains an N-terminal C3HC4-type RING-HC finger followed by a WWE domain with a poly(ADP-ribose) (PAR) binding motif at the tail.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 392894943 254 QCSICLEN-KNPSALFCGHLFCWTCIQehavaatsSASTSSARCPQCRLEF 303
Cdd:cd16546    2 ECPICLQTcIHPVKLPCGHIFCYLCVK--------GVAWQSKRCALCRQEI 44

RING finger, HC subclass, found in RING finger protein 169 (RNF169) and similar proteins; RNF169 is an uncharacterized E3 ubiquitin-protein ligase paralogous to RNF168. It functions as a negative regulator of the DNA damage signaling cascade. RNF169 recognizes polyubiquitin structures but does not itself contribute to double-strand break (DSB)-induced chromatin ubiquitylation. It contributes to regulation of the DSB repair pathway utilization via functionally competing with recruiting repair factors, 53BP1 and RAP80-BRCA1, for association with RNF168-modified chromatin independent of its catalytic activity, limiting the magnitude of the RNF8/RNF168-dependent signaling response to DSBs. RNF169 contains an N-terminal C3HC4-type RING-HC finger and a C-terminal MIU (motif interacting with ubiquitin) domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 392894943 253 FQCSICLE-NKNPSALFCGHLFCWTCIQEhavaaTSSASTSSARCPQCR 300
Cdd:cd16551    2 LTCAGCLEvPVEPATLPCGHTLCRGCANR-----ALDAAEAGPTCPRCR 45

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 392894943  254 QCSICLEN-KNPSALF-CGHLFCWTCIqehavaatSSASTSSARCPQC 299
Cdd:pfam13923   1 MCPICMDMlKDPSTTTpCGHVFCQDCI--------LRALEASNECPLC 40

RING finger, HC subclass, found in human homolog of Drosophila ariadne (HHARI) and similar proteins; This subfamily includes Drosophila melanogaster protein ariadne-1 (ARI-1), and its eukaryotic homologs, such as HHARI. ARI-1 is a widely expressed Drosophila RING-finger protein that localizes mainly in the cytoplasm and is required for neural development. It interacts with a novel ubiquitin-conjugating enzyme, UbcD10. HHARI, also known as H7-AP2, monocyte protein 6 (MOP-6), protein ariadne-1 homolog, Ariadne RBR E3 ubiquitin protein ligase 1 (ARIH1), ariadne-1 (ARI-1), UbcH7-binding protein, UbcM4-interacting protein, or ubiquitin-conjugating enzyme E2-binding protein 1, is an RBR-type E3 ubiquitin-protein ligase highly expressed in nuclei, where it is co-localized with nuclear bodies including Cajal, PML, and Lewy bodies. It interacts with the E2 conjugating enzymes UbcH7, UbcH8, UbcM4, and UbcD10 in human, mouse, and fly, and modulates the ubiquitylation of substrate proteins including single-minded 2 (SIM2) and translation initiation factor 4E homologous protein (4EHP). It functions as a potent mediator of DNA damage-induced translation arrest, which protects stem and cancer cells against genotoxic stress by initiating a 4EHP-mediated mRNA translation arrest. HHARI 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.

                         10        20        30
                 ....*....|....*....|....*....|
gi 392894943 255 CSICLENKNPSALF---CGHLFCWTCIQEH 281
Cdd:cd16626    3 CDICYLNYPNSYMTgleCGHKFCMQCWKEY 32

RING finger, HC subclass, found in tripartite motif-containing protein 2 (TRIM2); TRIM2, also known as RING finger protein 86 (RNF86), is an E3 ubiquitin-protein ligase that ubiquitinates the neurofilament light chain, a component of the intermediate filament in axons. Loss of function of TRIM2 results in early-onset axonal neuropathy. TRIM2 also plays a role in mediating the p42/p44 MAPK-dependent ubiquitination of the cell death-promoting protein Bcl-2-interacting mediator of cell death (Bim) in rapid ischemic tolerance. TRIM2 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLEN-KNPSALFCGHLFCWTCIQEHAVAATSSAStssarCPQCR 300
Cdd:cd16767    9 CSICLDRyKNPKVLPCLHTFCERCLQNYIPAHSLTLS-----CPVCR 50

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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 392894943 255 CSICLENK-NPSALFCGHLFCWTCIQEhavaatsSASTSSARCPQCRLEFQPRDVTP 310
Cdd:cd16596   12 CPICLDPFvEPVSIECGHSFCQECISQ-------VGKGGGSVCPVCRQRFLLKNLRP 61

RING finger, HC subclass, found in SH3 domain-containing RING finger proteins SH3RF1, SH3RF2, SH3RF3, and similar proteins; SH3RF1, also known as plenty of SH3s (POSH), RING finger protein 142 (RNF142), or SH3 multiple domains protein 2 (SH3MD2), is a trans-Golgi network-associated pro-apoptotic scaffold protein with E3 ubiquitin-protein ligase activity. SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH) that is required for pro-apoptotic JNK activation. SH3RF3, also known as plenty of SH3s 2 (POSH2) or SH3 multiple domains protein 4 (SH3MD4), is a scaffold protein with E3 ubiquitin-protein ligase activity. It was identified in the screen for interacting partners of p21-activated kinase 2 (PAK2) and may play a role in regulating c-Jun N-terminal kinase (JNK) mediated apoptosis in certain conditions. Members of this subfamily contain an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 392894943 254 QCSICLENKNPSA--LFCGHLFCWTCIQEHavaatsSASTSSARCPQCR 300
Cdd:cd16570    2 ECPVCLERLDVSAkvLPCQHTFCKRCLQII------VASRGELRCPECR 44

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 392894943 253 FQCSICLEN-KNPSALFCGHLFCWTCIQEHavaatssaSTSSARCPQCR 300
Cdd:cd16539    6 FACFICRKPfKNPVVTKCGHYFCEKCALKH--------YRKSKKCFVCG 46

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 392894943 254 QCSICLENKNPSALFCGHLFCWTCIQehavaatssastSSARCPQCR 300
Cdd:cd16520    2 LCPICMERKKNVVFLCGHGTCQKCAE------------KLKKCPICR 36

H2 subclass of RING (RING-H2) fingers and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers: some have different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). This family corresponds to the H2 subclass of RING (RING-H2) finger proteins that are characterized by containing C3H2C3-type canonical RING-H2 fingers or noncanonical RING-H2 finger variants, including C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type modified RING-H2 fingers. The canonical RING-H2 finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-H-X2-C-X(4-48)-C-X2-C, X is any amino acid and the number of X residues varies in different fingers. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-H2 finger can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serves as a scaffold for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 392894943 255 CSICLEN---KNPSALF-CGHLFCWTCIQEhavaatsSASTSSARCPQCR 300
Cdd:cd16448    1 CVICLEEfeeGDVVRLLpCGHVFHLACILR-------WLESGNNTCPLCR 43

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 392894943 255 CSICLENKN----PSALFCGHLFCWTCIQEHAVAATSSastssarCPQC 299
Cdd:cd00162    1 CPICREEMNdrrpVVLLSCGHTFSRSAIARWLEGSKQK-------CPFC 42