RING finger (Really Interesting New Gene) domain and U-box domain superfamily; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers: some have different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enable efficient transfer of ubiquitin from E2 to the substrates.

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gi 1584452185   6 RAPKILECLHTFCEECLTTLH-FRQDRLWRIGCPICRHKTPVP 47
Cdd:cd16556    15 KTPKLLDCGHTFCLECLARLSlASPPQAERVPCPLCRQPTVLP 57

RING finger, HC subclass, found in RING finger protein RNF183, RNF223, RNF225 and similar proteins; RNF183 is an E3 ubiquitin-protein ligase that is upregulated during intestinal inflammation and is negatively regulated by miR-7. It promotes intestinal inflammation by increasing the ubiquitination and degradation of inhibitor of kappa B, thereby resulting in secondary activation of the Nuclear factor-kappaB (NF-kB) pathway. The interaction between RNF183-mediated ubiquitination and miRNA may be an important novel epigenetic mechanism in the pathogenesis of inflammatory bowel disease (IBD). The biological function of RNF223 and RNF225 remains unclear. Members of this family contain an N-terminal C3HC4-type RING-HC finger.

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gi 1584452185   6 RAPKILECLHTFCEECLTTLH-FRQDRLWRIGCPICRHKTPVP 47
Cdd:cd16556    15 KTPKLLDCGHTFCLECLARLSlASPPQAERVPCPLCRQPTVLP 57

large tegument protein UL36; Provisional

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gi 1584452185   45 PVPDYRIINLPNNSKVTEAFPLyieadplPQDSLPPYPPPsryaAAPQQAEPEASESQAAAPTHTPRT 112
Cdd:PHA03247  2879 ARPPVRRLARPAVSRSTESFAL-------PPDQPERPPQP----QAPPPPQPQPQPPPPPQPQPPPPP 2935

RING finger, HC subclass, found in RING finger protein RNF183, RNF223, RNF225 and similar proteins; RNF183 is an E3 ubiquitin-protein ligase that is upregulated during intestinal inflammation and is negatively regulated by miR-7. It promotes intestinal inflammation by increasing the ubiquitination and degradation of inhibitor of kappa B, thereby resulting in secondary activation of the Nuclear factor-kappaB (NF-kB) pathway. The interaction between RNF183-mediated ubiquitination and miRNA may be an important novel epigenetic mechanism in the pathogenesis of inflammatory bowel disease (IBD). The biological function of RNF223 and RNF225 remains unclear. Members of this family contain an N-terminal C3HC4-type RING-HC finger.

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gi 1584452185   6 RAPKILECLHTFCEECLTTLH-FRQDRLWRIGCPICRHKTPVP 47
Cdd:cd16556    15 KTPKLLDCGHTFCLECLARLSlASPPQAERVPCPLCRQPTVLP 57

RING finger, HC subclass, found in RING finger protein 208 (RNF208) and similar proteins; RNF208 is an E3 ubiquitin-protein ligase whose activity can be modulated by S-nitrosylation. It contains a C3HC4-type RING-HC finger.

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gi 1584452185   1 FDLDRRAPKILECLHTFCEECLTTLHFRQDRLWRIGCPICRHKTPV 46
Cdd:cd16559    11 YNFTNKRPRILSCLHSVCEECLQILYESCPKYKFISCPTCKRETVL 56

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.

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gi 1584452185   1 FDLDRRAPKILECLHTFCEECLTTLHFrQDRLWRIGCPICR 41
Cdd:cd16587    10 FDEGQLRPKLLHCGHTICEQCLEKLLA-SLSINGVRCPFCR 49

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

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gi 1584452185   1 FDLDRRAPKILECLHTFCEECLTTLHFRQDRLwRIGCPICRHKTPVPD 48
Cdd:cd23140    11 YNEDERVPLLLQCGHTFCKDCLSQMFIRCTDL-TLKCPRCRQSVLVGN 57

RING finger, HC subclass, found in promyelocytic leukemia protein (PML) and similar proteins; Protein PML, also known as RING finger protein 71 (RNF71) or tripartite motif-containing protein 19 (TRIM19), is predominantly a nuclear protein with a broad intrinsic antiviral activity. It is the eponymous component of PML nuclear bodies (PML NBs) and has been implicated in a wide variety of cell processes, including DNA damage signaling, apoptosis, and transcription. PML interferes with the replication of many unrelated viruses, including human immunodeficiency virus 1 (HIV-1), human foamy virus (HFV), poliovirus, influenza virus, rabies virus, EMCV, adeno-associated virus (AAV), and vesicular stomatitis virus (VSV). It also selectively interacts with misfolded proteins through distinct substrate recognition sites and conjugates these proteins with the small ubiquitin-like modifiers (SUMOs) through its SUMO ligase activity. PML 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 1584452185   6 RAPKILECLHTFCEECLTTLHFRQDRLWRIGCPICR 41
Cdd:cd16579    15 KCPKLLPCLHTVCSGCLEALAEQASETTEFQCPICK 50

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 2(RNFT2); RNFT2, also known as transmembrane protein 118 (TMEM118), is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

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gi 1584452185   6 RAPKILECLHTFCEECLtTLHFRQDRlwriGCPICR 41
Cdd:cd16742    24 REPLILICQHVFCEECL-CLWFDRER----TCPLCR 54

RING finger, HC subclass, found in RING finger protein 182 (RNF182) and similar proteins; RNF182 is a brain-enriched E3 ubiquitin-protein ligase that stimulates E2-dependent polyubiquitination in vitro. It is upregulated in Alzheimer"s disease (AD) brains and neuronal cells exposed to injurious insults. It interacts with ATP6V0C and promotes its degradation by the ubiquitin-proteosome pathway, suggesting a very specific role in controlling the turnover of an essential component of the neurotransmitter release machinery. RNF182 contains an N-terminal C3HC4-type RING-HC finger, and a C-terminal transmembrane domain.

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gi 1584452185   1 FDLDRRAPKILECLHTFCEECLTTL-HFRQDRLWRIGCPICRHKT 44
Cdd:cd16555    11 YDLRQRRPKVLECCHRVCAKCLYKIvDLGDSSPSVLVCPFCRFET 55

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

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gi 1584452185   3 LDR-RAPKILECLHTFCEECLTTlhFRQDRLWRIGCPICR 41
Cdd:cd16768    11 LDRyHNPKVLPCLHTFCERCLQN--YIPPQSLTLSCPVCR 48

RING finger, HC subclass, found in tripartite motif-containing protein TRIM2, TRIM3, and similar proteins; 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. TRIM3, also known as brain-expressed RING finger protein (BERP), RING finger protein 97 (RNF97), or RING finger protein 22 (RNF22), is an E3 ubiquitin-protein ligase involved in the pathogenesis of various cancers. It also plays an important role in the central nervous system (CNS). In addition, TRIM3 may be involved in vesicular trafficking via its association with the cytoskeleton-associated-recycling or transport (CART) complex that is necessary for efficient transferrin receptor recycling, but not for epidermal growth factor receptor (EGFR) degradation. Both TRIM2 and TRIM3 belong 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.

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gi 1584452185   6 RAPKILECLHTFCEECLTTLHFRQDrlWRIGCPICR 41
Cdd:cd16586    12 KNPKVLPCLHTFCERCLQNYIPAES--LSLSCPVCR 45

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

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gi 1584452185   2 DLDRRAPKIL-ECLHTFCEECLTTLHFRQDRlwRIGCPICRHKT 44
Cdd:cd23124    14 DDPLLIPRILtECGHTICTNCAGTILGQSSG--SIFCPFDRIVT 55