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 24645897     91 CTICLDPLSVYTMVyLRCSHALHEKCLHQYQANGGRHCPVC 131
Cdd:smart00184   1 CPICLEEYLKDPVI-LPCGHTFCRSCIRKWLESGNNTCPIC 40

RING finger, H2 subclass, found in 43 kDa receptor-associated protein of the synapse (Rapsyn) and similar proteins; Rapsyn, also known as acetylcholine receptor (AChR)-associated 43 kDa protein or RING finger protein 205 (RNF205), is a 43 kDa postsynaptic protein that plays an essential role in the clustering and maintenance of AChR in the postsynaptic membrane of the motor endplate. AChRs enable the transport of rapsyn from the Golgi complex to the plasma membrane through a molecule-specific interaction. Rapsyn also mediates subsynaptic anchoring of protein kinase A (PKA) type I in close proximity to the postsynaptic membrane, which is essential for synapse maintenance. Its mutations in humans cause endplate AChR deficiency and myasthenic syndrome. Rapsyn contains an N-terminal myristoylation signal required for membrane association, seven tetratricopeptide repeats (TPRs) that subserve rapsyn self-association, a coiled-coil domain responsible for the binding of determinants within the long cytoplasmic loop of each AChR subunit, a C3H2C3-type RING-H2 finger that binds to the cytoplasmic domain of beta-dystroglycan and to S-NRAP and links rapsyn to the subsynaptic cytoskeleton, and a serine phosphorylation site.

                        10        20
                ....*....|....*....|....*..
gi 24645897 106 LRCSHALHEKCLHQYQANGGRHCPVCR 132
Cdd:cd16478  21 LPCSHIFHLKCLQTNLRGGTRGCPNCR 47

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.

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                ....*....|....*....|....*....|....*....|....*....|
gi 24645897  91 CTICLDPL---SVYTMVYLRCSHALHEKCLHQYQANGGRHCPVCRMGIKE 137
Cdd:cd23114   7 CSICLETMkpgSGHAIFTAECSHSFHFECIAGNVRHGNLRCPVCRAKWKE 56

RING finger, H2 subclass, found in RING finger protein 167 (RNF167) and similar proteins; RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) ubiquitination. It ubiquitinates AMPA-type glutamate receptor subunit GluA2 and regulates its surface expression, and thus acts as a selective regulator of AMPAR-mediated neurotransmission. It acts as an endosomal membrane protein which ubiquitylates vesicle-associated membrane protein 3 (VAMP3) and regulates endosomal trafficking. Moreover, RNF167 plays a role in the regulation of TSSC5 (tumor-suppressing subchromosomal transferable fragment cDNA, also known as ORCTL2/IMPT1/BWR1A/SLC22A1L), which can function in concert with the ubiquitin-conjugating enzyme UbcH6. RNF167 is widely conserved in metazoans and contains an N-terminal signal peptide, a protease-associated (PA) domain, two transmembrane domains (TM1 and TM2), and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

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                ....*....|....*....|....*....|....*....|....*
gi 24645897  89 DLCTICLDPLSVY-TMVYLRCSHALHEKCLHQYQANGGRHCPVCR 132
Cdd:cd16797   1 DVCAICLDEYEEGdKLRVLPCSHAYHSKCVDPWLTQTKKTCPVCK 45

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 24645897  91 CTICLDPLsvYTMVYLRCSHALHEKCLHQYQANGGRHCPVCR 132
Cdd:cd16596  12 CPICLDPF--VEPVSIECGHSFCQECISQVGKGGGSVCPVCR 51

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase Deltex1 (DTX1), Deltex2 (DTX2), Deltex4 (DTX4), and similar proteins; This subfamily contains the vertebrate homologs of Drosophila melanogaster Deltex, specifically DTX1, DTX2, and DTX4, and other similar proteins mainly from eumetazoa. The vertebrate homologs of Deltex are involved in Notch signaling and neurogenesis. Mammalian DTX1 is most closely related to the Drosophila Deltex. Both of them bind to SH3-domain containing protein Grb2 and further inhibit E2A. DTX1 functions as a Notch downstream transcription regulator. It interacts with the transcription coactivator p300 and inhibits transcription activation mediated by the neural specific transcription factor MASH1. It is also a transcription target of nuclear factor of activated T cells (NFAT) and participates in T cell anergy and Foxp3 protein level maintenance in vivo. Moreover, DTX1 promotes protein kinase C theta degradation and sustains Casitas B-lineage lymphoma expression. DTX4, also known as RING finger protein 155, shares the highest degree of sequence similarity with DTX1. So it likely interacts with the intracellular domain of Notch as well. Like DTX1 and DTX4, DTX2 is expressed in thymocytes. It interacts with the intracellular domain of Notch receptors and acts as a negative regulator of Notch signals in T cells. However, the endogenous levels of DTX1 and DTX2 is not important for regulating Notch signals during thymocyte development. In contrast to other DTXs, DTX3 does not contain two Notch-binding WWE domains at the N-terminus, but rather a short unique N-terminal domain. It does not interact with the intracellular domain of Notch. In addition, it has a different class of RING finger (C3HC4 type or RING-HC subclass), compared with the other DTXs which harbor a C3H2C3-type RING-H2 finger. Thus DTX3 is not included in this subfamily. Drosophila melanogaster Deltex also does not belong to this subfamily.

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                ....*....|....*....|....*....|....*....|....*....|....*....
gi 24645897  91 CTICLDPL---SVYTMVYL----------RCSHALHEKCLHQY----QANGGRHCPVCR 132
Cdd:cd16459   2 CPICCEPLcvaSGYEESKLegskvvvrlkKCSHMYHKACLVAMysngAKDGSLQCPTCK 60

RING finger, HC subclass, found in radiation sensitivity protein 5 (RAD5) and similar proteins; RAD5, also known as revertibility protein 2 (REV2), or DNA repair protein RAD5, is a probable helicase, and a member of the UBC2/RAD6 epistasis group. It functions with the DNA repair protein RAD18 in error-free postreplication DNA repair. It is involved in the maintenance of wild-type rates of instability of simple repetitive sequences such as poly(GT) repeats. It may also be involved in maintaining a balance which acts in favor of error-prone non-homologous joining during DNA double-strand breaks repairs. It recruits the UBC13-MMS2 dimer to chromatin for DNA repair. RAD5 contains a typical C3HC4-type RING-HC finger.

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                ....*....|....*....|....*....|....*....|....*....|...
gi 24645897  91 CTICL-DPLSVYTMVYLRCSHALHEKCLHQY-----QANGGRHCPVCRMGIKE 137
Cdd:cd23131   6 CSICTqEPIEVGEVVFTECGHSFCEDCLLEYiefqnKKKLDLKCPNCREPISK 58

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

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                ....*....|....*....|....*....|....*....|...
gi 24645897  91 CTICLDPLSVYTMVY-LRCSHALHEKCLHQYQANGGRHCPVCR 132
Cdd:cd16448   1 CVICLEEFEEGDVVRlLPCGHVFHLACILRWLESGNNTCPLCR 43

RING finger, H2 subclass, found in RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), and similar proteins; This subfamily includes RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), Zinc/RING finger protein 4 (ZNRF4), and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane domain (TM), and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that functions in the regulation of cancer development, muscle cell growth, and neuronal development. Its expression is developmentally regulated during myogenesis and is upregulated in various tumors. RNF13 negatively regulates cell proliferation through its E3 ligase activity. RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in the ubiquitination of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). It acts as an endosomal membrane protein which ubiquitylates vesicle-associated membrane protein 3 (VAMP3) and regulates endosomal trafficking. Moreover, RNF167 plays a role in the regulation of TSSC5 (tumor-suppressing subchromosomal transferable fragment cDNA, also known as ORCTL2/IMPT1/BWR1A/SLC22A1L), which can function in concert with the ubiquitin-conjugating enzyme UbcH6. ZNRF4, also known as RING finger protein 204 (RNF204), or Nixin, is an endoplasmic reticulum (ER) membrane-anchored ubiquitin ligase that physically interacts with the ER-localized chaperone calnexin in a glycosylation-independent manner, inducing calnexin ubiquitination, and p97-dependent degradation. The murine protein sperizin (spermatid-specific ring zinc finger) is a homolog of human ZNRF4. It is specifically expressed in Haploid germ cells and is involved in spermatogenesis.

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gi 24645897  89 DLCTICLDPLSVYTMV-YLRCSHALHEKCLHQYQANGGRHCPVCR 132
Cdd:cd16665   1 DVCAICLDDYEEGDKLrILPCSHAYHCKCIDPWLTKNKRTCPVCK 45

RING finger, H2 subclass, found in vacuolar protein sorting-associated protein 11 homolog (Vps11) and similar proteins; Vps11, also known as RING finger protein 108 (RNF108), is a soluble protein involved in regulation of glycolipid degradation and retrograde toxin transport. It is highly expressed in heart and pancreas. Vps11 associates with Vps16, Vps18, and Vps33 to form a Class C Vps core complex that is required for soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE)-mediated membrane fusion at the lysosome-like yeast vacuole. The core complex, together with two additional compartment-specific subunits, forms the tethering complexes HOPS (homotypic vacuole fusion and protein sorting) and CORVET (class C core vacuole/endosome transport). CORVET contains the additional Vps3 and Vps8 subunits. It operates at endosomes, controls traffic into late endosomes and interacts with the Rab5/Vps21-GTP form. HOPS contains the additional Vps39 and Vps41 subunits. It operates at the lysosomal vacuole, controls all traffic from late endosomes into the vacuole and interacts with the Rab7/Ypt7-GTP form. Vps11 is a central scaffold protein upon which both HOPS and CORVET assemble. The HOPS and CORVET complexes disassemble in the absence of Vps11, resulting in massive fragmentation of vacuoles. Vps11 contains a clathrin repeat domain and a C-terminal C3H2C3-type RING-H2 finger. This subfamily also includes Vps11 homologs found in fungi, such as Saccharomyces cerevisiae vacuolar membrane protein Pep5p, also known as carboxypeptidase Y-deficient protein 5, vacuolar morphogenesis protein 1, or vacuolar biogenesis protein END1. Pep5p is essential for vacuolar biogenesis. It associates with Pep3p to form a core Pep3p/Pep5p complex that promotes vesicular docking/fusion reactions in conjunction with SNARE proteins at multiple steps in transport routes to the vacuole.

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gi 24645897  91 CTICLDPLSVyTMVYLRCSHALHEKCLHQYQANgGRHCPVCR 132
Cdd:cd16688   3 CSACGSTLDL-PSVHFLCGHSFHQHCLEDYEEN-DRECPLCA 42

RING finger, HC subclass, found in RING finger protein 138 (RNF138) and similar proteins; RNF138, also known as Nemo-like kinase-associated RING finger protein (NARF) or NLK-associated RING finger protein, is an E3 ubiquitin-protein ligase that plays an important role in glioma cell proliferation, apoptosis, and cell cycle. It specifically cooperates with the E2 conjugating enzyme E2-25K (Hip-2/UbcH1), regulates the ubiquitylation and degradation of T cell factor/lymphoid enhancer factor (TCF/LEF), and further suppresses Wnt-beta-catenin signaling. RNF138, together with three closely related proteins: RNF114, RNF125 and RNF166, 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).

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gi 24645897  90 LCTICLDPLS--VYTMVylrCSHALHEKCLHQYQANGGRHCPVCR 132
Cdd:cd16544   4 TCPVCQEVLKdpVELPP---CRHIFCKACILLALRSSGARCPLCR 45