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 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd23137    1 DDYACPICMNVAWKPVRLECSHVFCLRCLVKAQKQKKDNCPLCR 44

RING finger, HC subclass, found in Candida albicans transcriptional regulator of yeast form adherence 3 (TRY3) and similar proteins; TRY3 acts as a transcription factor required for yeast cell adherence to silicone substrate. It contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd23137    1 DDYACPICMNVAWKPVRLECSHVFCLRCLVKAQKQKKDNCPLCR 44

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

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gi 328849261   345 CPICREIAYK-PVKMNCGHRFCVRCLVKLQKSSEDRCPVC 383
Cdd:smart00184   1 CPICLEEYLKdPVILPCGHTFCRSCIRKWLESGNNTCPIC 40

RING-finger-containing E3 ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 328849261 340 LENYECPICREIAYKPVKMNCGHRFCVRCLV-KLQKSSEDRCPVCRQCVVL 389
Cdd:COG5574  213 LADYKCFLCLEEPEVPSCTPCGHLFCLSCLLiSWTKKKYEFCPLCRAKVYP 263

N1R/p28-like protein; Provisional

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                 ....*....|....*....|....*....|....*....|....*....
gi 328849261 344 ECPICREIAY-KPVK-------MNCGHRFCVRCLVKLQKsSEDRCPVCR 384
Cdd:PHA02929 176 ECAICMEKVYdKEIKnmyfgilSNCNHVFCIECIDIWKK-EKNTCPVCR 223

RING finger, HC subclass, found in Candida albicans transcriptional regulator of yeast form adherence 3 (TRY3) and similar proteins; TRY3 acts as a transcription factor required for yeast cell adherence to silicone substrate. It contains a typical C3HC4-type RING-HC finger.

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gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd23137    1 DDYACPICMNVAWKPVRLECSHVFCLRCLVKAQKQKKDNCPLCR 44

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.

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gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVC 383
Cdd:cd16449    1 LECPICLERLKDPVLLPCGHVFCRECIRRLLESGSIKCPIC 41

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 328849261 341 ENYECPICREIAYKPVK-MNCGHRFCVRCLVKLQKSSEDRCPVCRQCV 387
Cdd:cd16544    1 AELTCPVCQEVLKDPVElPPCRHIFCKACILLALRSSGARCPLCRGPV 48

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) and similar proteins; TRAF6, also known as interleukin-1 signal transducer or RING finger protein 85 (RNF85), is a cytoplasmic adapter protein that mediates signals induced by the tumor necrosis factor receptor (TNFR) superfamily and Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) family. It functions as a mediator involved in the activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways, as well as in IL-1R-mediated activation of NF-kappaB. TRAF6 is also an oncogene that plays a vital role in K-RAS-mediated oncogenesis. TRAF6 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

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gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPV 382
Cdd:cd16643    2 YECPICLMALREPVQTPCGHRFCKACILKSIREAGHKCPV 41

zinc finger of C3HC4-type, RING; This is a family of primate-specific Ret finger protein-like (RFPL) zinc-fingers of the C3HC4 type. Ret finger protein-like proteins are primate-specific target genes of Pax6, a key transcription factor for pancreas, eye and neocortex development. This domain is likely to be DNA-binding. This zinc-finger domain together with the RDM domain, pfam11002, forms a large zinc-finger structure of the RING/U-Box superfamily. RING-containing proteins are known to exert an E3 ubiquitin protein ligase activity with the zinc-finger structure being mandatory for binding to the E2 ubiquitin-conjugating enzyme.

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gi 328849261  345 CPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDR---CPVC 383
Cdd:pfam15227   1 CPICLDYLEKPVSIECGHSFCLSCINSLQKEPDGEsllCPQC 42

RING finger, HC subclass, found in RING finger protein 114 (RNF114) and similar proteins; RNF114, also known as zinc finger protein 228 (ZNF228) or zinc finger protein 313 (ZNF313), is a p21(WAF1)-targeting ubiquitin E3 ligase that interacts with X-linked inhibitor of apoptosis (XIAP)-associated factor 1 (XAF1) and may play a role in p53-mediated cell-fate decisions. It is involved in the immune response to double-stranded RNA in disease pathogenesis. Moreover, RNF114 interacts with A20 and modulates its ubiquitylation. It negatively regulates nuclear factor-kappaB (NF-kappaB)-dependent transcription and positively regulates T-cell activation. RNF114 may play a putative role in the regulation of immune responses, since it corresponds to a novel psoriasis susceptibility gene, ZNF313. RNF114, together with three closely related proteins: RNF125, RNF138 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 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd16540    2 FTCPVCLEIFETPVRVPCGHVFCNACLQECLKPKKPVCAVCR 43

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 328849261 337 VPILENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSS-----EDRCPVCR 384
Cdd:cd16591    1 VNIKEEVTCPICLELLTEPLSLDCGHSFCQACITANHKESvnqegESSCPVCR 53

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

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gi 328849261 341 ENYECPICREIAYKP-VKMNCGHRFCVRCLVKLQKSS--EDRCPVCRQ 385
Cdd:cd16554    1 ESLTCPVCLDLYYDPyMCYPCGHIFCEPCLRQLAKSSpkNTPCPLCRT 48

RING finger, HC subclass, found in RING finger protein 213 (RNF213) and similar proteins; RNF213, also known as ALK lymphoma oligomerization partner on chromosome 17 or Moyamoya steno-occlusive disease-associated AAA+ and RING finger protein (mysterin), is an intracellular soluble protein that functions as an E3 ubiquitin-protein ligase and AAA+ ATPase, which possibly contributes to vascular development through mechanical processes in the cell. It plays a unique role in endothelial cells for proper gene expression in response to inflammatory signals from the environment. Mutations in RNF213 may be associated with Moyamoya disease (MMD), an idiopathic cerebrovascular occlusive disorder prevalent in East Asia. It also acts as a nuclear marker for acanthomorph phylogeny. RNF213 contains two tandem enzymatically active AAA+ ATPase modules and a C3HC4-type RING-HC finger. It can form a huge ring-shaped oligomeric complex.

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gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVK-LQKSSedRCPVCRQCV 387
Cdd:cd16561    1 GEQECSICLEDLNDPVKLPCDHVFCEECIRQwLPGQM--SCPLCRTEL 46

RING finger, HC subclass, found in bifunctional apoptosis regulator (BAR); BAR, also known as RING finger protein 47, was originally identified as an inhibitor of Bax-induced apoptosis. It participates in the block of apoptosis induced by TNF-family death receptors (extrinsic pathway) and mitochondria-dependent apoptosis (intrinsic pathway). BAR is predominantly expressed by neurons in the central nervous system and is involved in the regulation of neuronal survival. It is an endoplasmic reticulum (ER)-associated RING-type E3 ubiquitin ligase that interacts with BI-1 protein and post-translationally regulates its stability, as well as functioning in ER stress. BAR contains an N-terminal C3HC4-type RING-HC finger, a SAM domain, a coiled-coil domain, and a C-terminal transmembrane (TM) domain. This model corresponds to the RING-HC finger responsible for the binding of ubiquitin conjugating enzymes (E2s).

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gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDR-CPVCRQ 385
Cdd:cd16497    2 FLCHCCYDLLVNPTTLNCGHSFCRHCLALWWKSSKKTeCPECRQ 45

RING finger, HC subclass, found in checkpoint with forkhead and RING finger domains protein (CHFR); CHFR, also known as RING finger protein 196 (RNF196), is a checkpoint protein that delays entry into mitosis in response to stress. It functions as an E3 ubiquitin ligase that ubiquitinates and degrades its target proteins, such as Aurora-A, Plk1, Kif22, and PARP-1, which are critical for proper mitotic transitions. It also plays an important role in cell cycle progression and tumor suppression, and is negatively regulated by SUMOylation-mediated proteasomal ubiquitylation. Moreover, CHFR is involved in the early stage of the DNA damage response, which mediates the crosstalk between ubiquitination and poly-ADP-ribosylation. CHFR contains a fork head associated (FHA) domain and a C3HC4-type RING-HC finger.

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gi 328849261 341 ENYECPICREIAYKPVKMN-CGHRFCVRCLVKLQKSSEDRCPVCRQCV 387
Cdd:cd16503    1 ENLTCSICQDLLHDCVSLQpCMHNFCAACYSDWMERSNTECPTCRATV 48

RING finger, HC subclass, found in RING finger protein 125 (RNF125); RNF125, also known as T-cell RING activation protein 1 (TRAC-1), is an E3 ubiquitin-protein ligase that is predominantly expressed in lymphoid cells, and functions as a positive regulator of T cell activation. It also down-modulates HIV replication and inhibits pathogen-induced cytokine production. It negatively regulates type I interferon signaling, which conjugates Lys(48)-linked ubiquitination to retinoic acid-inducible gene-I (RIG-I) and subsequently leads to the proteasome-dependent degradation of RIG-I. Further, RNF125 conjugates ubiquitin to melanoma differentiation-associated gene 5 (MDA5), a family protein of RIG-I. It thus acts as a negative regulator of RIG-I signaling, and is a direct target of miR-15b in the context of Japanese encephalitis virus (JEV) infection. Moreover, RNF125 binds to and ubiquitinates JAK1, prompting its degradation and inhibition of receptor tyrosine kinase (RTK) expression. It also negatively regulates p53 function through physical interaction and ubiquitin-mediated proteasome degradation. Mutations in RNF125 may lead to overgrowth syndromes (OGS). RNF125, together with three closely related proteins: RNF114, RNF138 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). The UIM of RNF125 binds K48-linked poly-ubiquitin chains and is, together with the RING domain, required for auto-ubiquitination.

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gi 328849261 342 NYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd16542    1 NFDCAVCLEVLHQPVRTRCGHVFCRPCIATSLRNNTWTCPYCR 43

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRCL---VKLQKSSEDRCPVCRQC 386
Cdd:cd16597    8 CSICLELFKDPVTLPCGHNFCGVCIektWDSQHGSEYSCPQCRAT 52

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM60, TRIM61, TRIM75 and similar proteins; TRIM60, also known as RING finger protein 129 (RNF129) or RING finger protein 33 (RNF33), is a cytoplasmic protein expressed in the testis. It may play an important role in the spermatogenesis process, the development of the preimplantation embryo, and in testicular functions. RNF33 interacts with the cytoplasmic kinesin motor proteins KIF3A and KIF3B suggesting possible contribution to cargo movement along the microtubule in the expressed sites. It is also involved in spermatogenesis in Sertoli cells under the regulation of nuclear factor-kappaB (NF-kappaB). TRIM75 mainly localizes within spindles, suggesting it may function in spindle organization and thereby affect meiosis. Both TRIM60 and TRIM75 belong 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 B2-box, and two coiled coil domains, as well as a PRY domain and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. In contrast, TRIM61 belongs to the C-V subclass of the TRIM family that contains RBCC domains only. Its biological function remains unclear.

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gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDR--CPVCRQC 386
Cdd:cd16607    4 CPICLDYLKDPVTINCGHNFCRSCISMSWKDLQDTfpCPVCRFC 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.

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gi 328849261 344 ECPICREIAYKPVKMNCGHRFCVRClVKLQKSSEDRCPVCRQ 385
Cdd:cd16546    2 ECPICLQTCIHPVKLPCGHIFCYLC-VKGVAWQSKRCALCRQ 42

RING finger, HC subclass, found in tripartite motif-containing protein TRIM50, TRIM73, TRIM74 and similar proteins; TRIM50 is a stomach-specific E3 ubiquitin-protein ligase, encoded by the Williams-Beuren syndrome (WBS) TRIM50 gene, which regulates vesicular trafficking for acid secretion in gastric parietal cells. It colocalizes, interacts with, and increases the level of p62/SQSTM1, a multifunctional adaptor protein implicated in various cellular processes including the autophagy clearance of polyubiquitinated protein aggregates. It also promotes the formation and clearance of aggresome-associated polyubiquitinated proteins through the interaction with histone deacetylase 6 (HDAC6), a tubulin specific deacetylase that regulates microtubule-dependent aggresome formation. TRIM50 can be acetylated by PCAF and p300. TRIM50 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. This subfamily also includes two paralogs of TRIM50, tripartite motif-containing protein 73 (TRIM73), also known as tripartite motif-containing protein 50B (TRIM50B), and tripartite motif-containing protein 74 (TRIM74), also known as tripartite motif-containing protein 50C (TRIM50C), both of which are WBS-related genes encoding proteins that may also act as E3 ligases. In contrast with TRIM50, TRIM73 and TRIM74 belong to the C-V subclass of TRIM family of proteins that are defined by N-terminal RBCC domains only.

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gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRCLVKL--QKSSEDRCPVCRQ 385
Cdd:cd16605    3 CPICLEVFKEPLMLQCGHSYCKSCLVSLsgELDGQLLCPVCRQ 45

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.

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                 ....*....|....*....|....*....|....*....|....
gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVK-LQKSSEDR-CPVCR 384
Cdd:cd16745    1 FECNICLDLAQDPVVTLCGHLFCWPCLHKwLRRQSSQPeCPVCK 44

RING finger, HC subclass, found in Mus musculus tripartite motif-containing protein 43 (TRIM43) and similar propteins; This subfamily includes TRIM43A, TRIM43B and TRIM43C, which are expressed specifically in mouse preimplantation embryos. They contain a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQK--SSEDRCPVCRQ 385
Cdd:cd23133    2 ETLTCSICQGIFMNPVYLRCGHKFCEACLLLFQEdiKFPAYCPMCRQ 48

RING finger, HC subclass, found in ubiquitin-like PHD and RING finger domain-containing proteins, UHRF1 and UHRF2, and similar proteins; UHRF1 is a unique chromatin effector protein that integrates the recognition of both histone PTMs and DNA methylation. It is essential for cell proliferation and plays a critical role in the development and progression of many human carcinomas, such as laryngeal squamous cell carcinoma (LSCC), gastric cancer (GC), esophageal squamous cell carcinoma (ESCC), colorectal cancer, prostate cancer, and breast cancer. UHRF1 acts as a transcriptional repressor through its binding to histone H3 when it is unmodified at Arg2. Its overexpression in human lung fibroblasts results in downregulation of expression of the tumor suppressor pRB. It also plays a role in transcriptional repression of the cell cycle regulator p21. Moreover, UHRF1-dependent repression of transcription factors can facilitate the G1-S transition. It interacts with Tat-interacting protein of 60 kDa (TIP60) and induces degradation-independent ubiquitination of TIP60. It is also an N-methylpurine DNA glycosylase (MPG)-interacting protein that binds MPG in a p53 status-independent manner in the DNA base excision repair (BER) pathway. In addition, UHRF1 functions as an epigenetic regulator that is important for multiple aspects of epigenetic regulation, including maintenance of DNA methylation patterns and recognition of various histone modifications. UHRF2 was originally identified as a ubiquitin ligase acting as a small ubiquitin-like modifier (SUMO) E3 ligase that enhances zinc finger protein 131 (ZNF131) SUMOylation, but does not enhance ZNF131 ubiquitination. It also ubiquitinates PCNP, a PEST-containing nuclear protein. Moreover, UHRF2 functions as a nuclear protein involved in cell-cycle regulation and has been implicated in tumorigenesis. It interacts with cyclins, CDKs, p53, pRB, PCNA, HDAC1, DNMTs, G9a, methylated histone H3 lysine 9, and methylated DNA. It interacts with the cyclin E-CDK2 complex, ubiquitinates cyclins D1 and E1, induces G1 arrest, and is involved in the G1/S transition regulation. Furthermore, UHRF2 is a direct transcriptional target of the transcription factor E2F-1 in the induction of apoptosis. It recruits HDAC1 and binds to methyl-CpG. UHRF2 also participates in the maturation of Hepatitis B virus (HBV) by interacting with the HBV core protein and promoting its degradation. Both UHRF1 and UHRF2 contain an N-terminal ubiquitin-like domain (UBL), a tandem Tudor domain (TTD), a plant homeodomain (PHD) finger, a SET- and RING-associated (SRA) domain, and a C-terminal C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCRQ 385
Cdd:cd16613    1 FTCICCQELVYKPITTPCKHNICKSCLQRSFKAEVYTCPACRH 43

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 328849261  344 ECPICRE---IAYKPVKMNCGHRFCVRCLVKLQKSSEdRCPVCR 384
Cdd:pfam13639   2 ECPICLEefeEGDKVVVLPCGHHFHRECLDKWLRSSN-TCPLCR 44

RING finger, HC subclass, found in tripartite motif-containing protein TRIM58 and similar proteins; TRIM58, also known as protein BIA2, is an erythroid E3 ubiquitin-protein ligase induced during late erythropoiesis. It binds and ubiquitinates the intermediate chain of the microtubule motor dynein (DYNC1LI1/DYNC1LI2), stimulating the degradation of the dynein holoprotein complex. It may participate in the erythroblast enucleation process through regulation of nuclear polarization. TRIM58 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSED------RCPVCR 384
Cdd:cd16606    1 EEARCPVCLDFLQEPVSVDCGHSFCLRCISEFCEKSDSaqggvyACPQCR 50

first RING finger, HC subclass, found in Arabidopsis thaliana ORTHRUS and similar proteins; This subfamily includes Arabidopsis thaliana ORTHRUS 1-5. They are E3 ubiquitin-protein ligases that may participate in CpG methylation-dependent transcriptional regulation and/or epigenetic transcriptional silencing. ORTHRUS 1 mediates ubiquitination with the E2 ubiquitin-conjugating enzymes UBC11, UBC8 and UBC8 homologs (e.g. UBC10, UBC11, UBC28 and UBC29) but not with UBC27, UBC30, UBC32, UBC34 and UBC36. ORTHRUS 2 and 5 mediate ubiquitination with the E2 ubiquitin-conjugating enzyme UBC11. ORTHRUS 1 and 2 promote methylation-mediated gene silencing leading, for example, to early flowering. They can bind to CpG, CpNpG, and CpNpN DNA motifs, with a strong preference for methylated forms, and with highest affinity for CpG substrates. Members of this subfamily contain two typical C3HC4-type RING-HC fingers. This model corresponds to the first one.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd23138    1 DELNCSFCMQLPERPVTTPCGHNFCLKCFQKWMGQGKKTCGTCR 44

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 7 (TRAF7) and similar proteins; TRAF7, also known as RING finger and WD repeat-containing protein 1 or RING finger protein 119 (RNF119), is an E3 ubiquitin-protein ligase involved in signal transduction pathways that lead either to activation or repression of NF-kappaB transcription factor by promoting K29-linked ubiquitination of several cellular targets, including the NF-kappaB essential modulator (NEMO) and the p65 subunit of NF-kappaB transcription factor. It is also involved in K29-linked polyubiquitination that has been implicated in lysosomal degradation of proteins. Moreover, TRAF7 is required for K48-linked ubiquitination of p53, a key tumor suppressor and a master regulator of various signaling pathways, such as those related to apoptosis, cell cycle and DNA repair. It is also required for tumor necrosis factor alpha (TNFalpha)-induced Jun N-terminal kinase activation and promotes cell death by regulating polyubiquitination and lysosomal degradation of c-FLIP protein. Furthermore, TRAF7 functions as small ubiquitin-like modifier (SUMO) E3 ligase involved in other post-translational modification, such as sumoylation. It binds to and stimulates sumoylation of the proto-oncogene product c-Myb, a transcription factor regulating proliferation and differentiation of hematopoietic cells. It potentiates MEKK3-induced AP1 and CHOP activation and induces apoptosis. Meanwhile, TRAF7 mediates MyoD1 regulation of the pathway and cell-cycle progression in myoblasts. It also plays a role in Toll-like receptors (TLR) signaling. TRAF7 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and an adjacent zinc finger, and a unique C-terminal domain that comprises a coiled coil domain and seven WD40 repeats.

                         10        20        30
                 ....*....|....*....|....*....|....*...
gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRCLVklqKSSEDRCPV 382
Cdd:cd16644    8 CPLCQRVFKDPVITSCGHTFCRRCAL---TAPGEKCPV 42

RING finger, HC subclass, found in tumor necrosis factor (TNF) receptor-associated factor 3 (TRAF3) and similar proteins; TRAF3, also known as CAP-1, CD40 receptor-associated factor 1 (CRAF1), CD40-binding protein (CD40BP), or LMP1-associated protein 1 (LAP1), is a member of the TRAF protein family, which mainly functions in the immune system, where it mediates signaling through tumor necrosis factor receptors (TNFRs) and interleukin-1/Toll-like receptors (IL-1/TLRs). It also plays a unique cell type-specific and critical role in the restraint of B-cell homeostatic survival, a role with important implications for both B-cell differentiation and the pathogenesis of B-cell malignancies. TRAF3 differentially regulates differentiation of specific T cell subsets. It is required for iNKT cell development, restrains Treg cell development in the thymus, and plays an essential role in the homeostasis of central memory CD8+ T cells. TRAF3 contains an N-terminal domain with a typical C3HC4-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain, and a conserved TRAF-C domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVC 383
Cdd:cd16640    1 YKCEKCRLVLCNPKQTECGHRFCESCMNALLSSSNPQCPAC 41

RING finger, HC subclass, found in constitutive photomorphogenesis protein 1 (COP1) and similar proteins; COP1, also known as RING finger and WD repeat domain protein 2 (RFWD2) or RING finger protein 200 (RNF200), is a central regulator of photomorphogenic development in plants, which targets key transcription factors for proteasome-dependent degradation. It is localized predominantly in the nucleus, but may also be present in the cytosol. Mammalian COP1 functions as an E3 ubiquitin-protein ligase that interacts with Jun transcription factors and modulates their transcriptional activity. It also interacts with and negatively regulates the tumor-suppressor protein p53. Moreover, COP1 associates with COP9 signalosome subunit 6 (CSN6), and is involved in 14-3-3sigma ubiquitin-mediated degradation. The CSN6-COP1 link enhances ubiquitin-mediated degradation of p27(Kip1), a critical CDK inhibitor involved in cell cycle regulation, to promote cancer cell growth. Furthermore, COP1 functions as the negative regulator of ETV1 and influences prognosis in triple-negative breast cancer. COP1 contains an N-terminal extension, a C3HC4-type RING-HC finger, a coiled coil domain, and seven WD40 repeats. In human COP1, a classic leucine-rich NES, and a novel bipartite NLS is bridged by the RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVK-LQKSSedRCPVC 383
Cdd:cd16504    3 FLCPICFDIIKEAFVTKCGHSFCYKCIVKhLEQKN--RCPKC 42

Variant RING finger, HC subclass (C4C4-type), found in retinoblastoma-binding protein 6 (RBBP6) and similar proteins; RBBP6, also known as proliferation potential-related protein, protein P2P-R, retinoblastoma-binding Q protein 1 (RBQ-1), or p53-associated cellular protein of testis (PACT), is a nuclear E3 ubiquitin-protein ligase involved in multiple processes, such as the control of gene expression, mitosis, cell differentiation, and cell apoptosis. It plays a role in both promoting and inhibiting apoptosis in many human cancers, including esophageal, lung, hepatocellular, and colon cancers, familial myeloproliferative neoplasms, as well as in human immunodeficiency virus-associated nephropathy (HIVAN). It functions as an Rb- and p53-binding protein that plays an important role in chaperone-mediated ubiquitination and possibly in protein quality control. It acts as a scaffold protein to promote the assembly of the p53/TP53-MDM2 complex, resulting in an increase of MDM2-mediated ubiquitination and degradation of p53/TP53, and leading to both apoptosis and cell growth. It is also a double-stranded RNA-binding protein that plays a role in mRNA processing by regulating the human polyadenylation machinery and modulating expression of mRNAs with AU-rich 3' untranslated regions (UTRs). Moreover, RBBP6 ubiquitinates and destabilizes the transcriptional repressor ZBTB38 that negatively regulates transcription and levels of the MCM10 replication factor on chromatin. Furthermore, RBBP6 is involved in tunicamycin-induced apoptosis by mediating protein kinase (PKR) activation. RBBP6 contains an N-terminal ubiquitin-like domain and a C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger. RBBP6 interacts with chaperones Hsp70 and Hsp40 through its N-terminal ubiquitin-like domain. It promotes the ubiquitination of p53 by Hdm2 in an E4-like manner through its RING finger. It also interacts directly with the pro-proliferative transcription factor Y-box-binding protein-1 (YB-1) via its RING finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 328849261 341 ENYECPICREIAYKPVKMNC-GHRFCVRCLVKLQKSSEDRCPVCRQCVVLD 390
Cdd:cd16620    2 DELKCPICKDLMKDAVLTPCcGNSFCDECIRTALLEEDFTCPTCKEPDVSP 52

RING finger, HC subclass, found in tripartite motif-containing protein 72 (TRIM72) and similar proteins; TRIM72, also known as Mitsugumin-53 (MG53), is a muscle-specific protein that plays a central role in cell membrane repair by nucleating the assembly of the repair machinery at muscle injury sites. It is required in repair of alveolar epithelial cells under plasma membrane stress failure. It interacts with dysferlin to regulate sarcolemmal repair. Upregulation of TRIM72 develops obesity, systemic insulin resistance, dyslipidemia, and hyperglycemia, as well as induces diabetic cardiomyopathy through transcriptional activation of the peroxisome proliferation-activated receptor alpha (PPAR-alpha) signaling pathway. Compensation for the absence of AKT signaling by ERK signaling during TRIM72 overexpression leads to pathological hypertrophy. Moreover, TRIM72 functions as a novel negative feedback regulator of myogenesis by targeting insulin receptor substrate-1 (IRS-1). It is transcriptionally activated by the synergism of myogenin (MyoD) and myocyte enhancer factor 2 (MEF2). TRIM72 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 328849261 345 CPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCRQCVVLdTTPRAL 396
Cdd:cd16612    7 CPLCLKLFQSPVTTECGHTFCQDCLSRVPKEEDGGSTSCPTCQAP-TKPEQL 57

RING finger, HC subclass, found in tumor necrosis factor (TNF) receptor-associated factor 2 (TRAF2) and similar proteins; TRAF2, also known as tumor necrosis factor type 2 receptor-associated protein 3, is an E3 ubiquitin-protein ligase that was identified as a 75 kDa tumor necrosis factor receptor (TNF-R2)-associated signaling protein. It interacts with members of the TNF receptor superfamily and connects the receptors to downstream signaling proteins. It also mediates K63-linked polyubiquitination of RIP1, a kinase pivotal in TNFalpha-induced NF-kappaB activation. Moreover, TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15. It also acts as an important biological suppressor of necroptosis. It inhibits TNF-related apoptosis inducing ligand (TRAIL)- and CD95L-induced apoptosis and necroptosis. TRAF2 contains an N-terminal domain with a typical C3HC4-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVC 383
Cdd:cd16639    2 YLCSDCRNILRRPFQAQCGHRYCSYCLKKILSSGPQKCAAC 42

RING finger, HC subclass, found in tripartite motif-containing protein 26 (TRIM26) and similar proteins; TRIM26, also known as acid finger protein (AFP), RING finger protein 95 (RNF95), or zinc finger protein 173 (ZNF173), is an E3 ubiquitin-protein ligase that negatively regulates interferon-beta production and antiviral response through polyubiquitination and degradation of nuclear transcription factor IRF3. It functions as an important regulator for RNA virus-triggered innate immune response by bridging TBK1 to NEMO (NF-kappaB essential modulator, also known as IKKgamma) and mediating TBK1 activation. It also acts as a novel tumor suppressor of hepatocellular carcinoma by regulating cancer cell proliferation, colony forming ability, migration, and invasion. TRIM26 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
                 ....*....|....*....|....*....|....*....|....*...
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDR----CPVCR 384
Cdd:cd16598    3 EEVTCSICLDYLRDPVTIDCGHNFCRSCITDYCPISGGHerpvCPLCR 50

RING finger, HC subclass, found in Arabidopsis thaliana protein CHROMATIN REMODELING 27 (CHR27) and similar proteins; CHR27, also called protein SNF2-RING-HELICASE-LIKE 1, is a probable helicase-like transcription factor involved in transcriptional gene silencing. It associates with SUVR2 and contributes to transcriptional gene silencing at RNA-directed DNA methylation (RdDM) target loci but also at RdDM-independent target loci. It may be involved in nucleosome positioning to form ordered nucleosome arrays on chromatin. It associates with SUVR2 and functions redundantly with FRG2. It is required for the efficient methylation of a broad range of RdDM target loci. CHR27 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 328849261 343 YECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSED-----RCPVCRQCVVLD 390
Cdd:cd23142    1 AICPICNDPPEDAVVTLCGHVFCCECVFQYLSSDRTcrqfnHCPLCRQKLYLD 53

RING finger, HC subclass, found in RING finger protein 8 (RNF8) and similar proteins; RNF8 is a telomere-associated E3 ubiquitin-protein ligase that plays an important role in DNA double-strand break (DSB) repair via histone ubiquitination. It is localized in the nucleus and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3), but not with other E2s (UbcH5, UbcH7, UbcH10, hCdc34, and hBendless). It recruits UBC13 for lysine 63-based self polyubiquitylation. Its deficiency causes neuronal pathology and cognitive decline, and its loss results in neuron degeneration. RNF8, together with RNF168, catalyzes a series of ubiquitylation events on substrates such as H2A and H2AX, with the H2AK13/15 ubiquitylation being particularly important for recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of DSBs. RNF8 mediates the ubiquitination of gammaH2AX, and recruits 53BP1 and BRCA1 to DNA damage sites which promotes DNA damage response (DDR) and inhibits chromosomal instability. Moreover, RNF8 interacts with retinoid X receptor alpha (RXR alpha) and enhances its transcription-stimulating activity. It also regulates the rate of exit from mitosis and cytokinesis. RNF8 contains an N-terminal forkhead-associated (FHA) domain and a C-terminal C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 328849261 344 ECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDrCPVCRQCVVLDTTPRALE 397
Cdd:cd16535    3 QCSICSELFIEAVTLNCSHSFCSYCITEWMKRKKE-CPICRKPITSKTRSLVLD 55

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        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRC--------LVKLQKSS--EDRCPVCRQ 385
Cdd:cd23127   11 CSICLDTVFDPVALGCGHLFCNSCacsaasvlIFQGLKAAppEAKCPLCRQ 61

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 328849261 345 CPICREI---AYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVC 383
Cdd:cd00162    1 CPICREEmndRRPVVLLSCGHTFSRSAIARWLEGSKQKCPFC 42

Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-1, Roquin-2, and similar proteins; The ROQUIN family includes Roquin-1, Roquin-2, and similar proteins, which localize to the cytoplasm and upon stress, are concentrated in stress granules. They may play essential roles in preventing T-cell-mediated autoimmune disease and in microRNA-mediated repression of inducible costimulator (Icos) mRNA. They function as E3 ubiquitin ligases consisting of an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 activity, a highly conserved ROQ domain required for RNA binding and localization to stress granules, and a CCCH-type zinc finger involved in RNA recognition.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 328849261 345 CPICR----EIAYKPVKMNCGHRFCVRCLVKLQKSsedRCP 381
Cdd:cd16638    4 CPVCTnefdGTQRKPISLGCGHTVCKTCLSKLHRK---QCP 41

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 328849261  344 ECPICREIAYKPVKMN-CGHRFCVRCLVK-LQKSseDRCPVC 383
Cdd:pfam13923   1 MCPICMDMLKDPSTTTpCGHVFCQDCILRaLRAG--NECPLC 40

RING finger, HC subclass, found in RING finger protein 151 (RNF151) and similar proteins; RNF151 is a testis-specific RING finger protein that interacts with dysbindin, a synaptic and microtubular protein that binds brain snapin, a SNARE-binding protein that mediates intracellular membrane fusion in both neuronal and non-neuronal cells. Thus, it may be involved in acrosome formation of spermatids by interacting with multiple proteins participating in membrane biogenesis and microtubule organization. RNF151 contains a C3HC4-type RING finger domain, a putative nuclear localization signal (NLS), and a TNF receptor associated factor (TRAF)-type zinc finger domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEdRCPVCRQCV 387
Cdd:cd16547    2 DDLICSICHGVLRCPVRLSCSHIFCKKCILQWLKRQE-TCPCCRKEV 47

Variant RING finger, HC subclass (C4C4-type), found in Ret finger protein-like (RFPL) family; The RFPL family, also known as the RING-B30 family, represents a group of RFPL gene products, RFPL1, RFPL2, RFPL3, and RFPL4A, which are characterized by containing an N-terminal RFPL1, 2, 3-specifying helix (RSH), a C4C4- or a variant C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger, an RFPL-defining motif (RDM), and C-terminal PRY/SPRY-forming B30.2 domain. RFPL1, also known as RING finger protein 78 (RNF78), is expressed during cell differentiation. RFPL2, also known as RING finger protein 79 (RNF79), shows high sequence similarity with other RFPL gene products. Its biological role remains unclear. RFPL3 interacts directly with CREB binding protein (CBP) in the nucleus of lung cancer cells. RFPL3 and CBP synergistically upregulate TERT activity and promote lung cancer growth. Moreover, RFPL3 acts as a novel E3 ubiquitin ligase modulating the integration activity of human immunodeficiency virus, type 1 (HIV-1) preintegration complex. RFPL4A, also known as RING finger protein 210 (RNF210), is a novel factor that increases the G1 population and decreases sensitivity to chemotherapy in human colorectal cancer cells. This model corresponds to the C4C4-type RING finger. RFPL4A lacks the fourth conserved zinc-binding residue, cysteine, and the eighth zinc-binding residue, cysteine; in RFPL2, it is replaced by serine.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRCLVKLQKSSEDRCPVCRQCVVL 389
Cdd:cd16621    3 CPVCSDYLEKPVSLECGYACCLQCLNSLQKEPHGEGLLCCCCSVV 47

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 328849261 341 ENYECPICREIAYKPVKMNCGHRFCVRCLVKLQKSSedrCPVCRQ 385
Cdd:cd16602    2 EEAVCAICLDYFKDPVSIGCGHNFCRVCVTQLWGFT---CPQCRK 43

RING finger, HC subclass, found in really interesting new gene proteins RING1, RING2 and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), is a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. Both RING1 and RING2 are core components of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING2 acts as the main E3 ubiquitin ligase on histone H2A of the PRC1 complex, while RING1 may rather act as a modulator of RNF2/RING2 activity. Members of this family contain a C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 328849261 345 CPICREIAYKP-VKMNCGHRFCVRCLVKLQKSSEDRCPVCR 384
Cdd:cd16531    4 CPICLGIIKNTmTVKECLHRFCAECIEKALRLGNKECPTCR 44

RING finger, HC subclass, found in RING finger protein 112 (RNF112) and similar proteins; RNF112, also known as brain finger protein (BFP), zinc finger protein 179 (ZNF179), or neurolastin, is a peripheral membrane protein that is predominantly expressed in the central nervous system and localizes to endosomes. It contains functional GTPase and C3HC4-type RING-HC finger domains and has been identified as a brain-specific dynamin family GTPase that affects endosome size and spine density. Moreover, RNF112 acts as a downstream target of sigma-1 receptor (Sig-1R) regulation and may play a novel role in neuroprotection by mediating the neuroprotective effects of dehydroepiandrosterone (DHEA) and its sulfated analog (DHEAS).

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 328849261 345 CPICREIAYKPVKMNCGHRFCVRCLV--KLQKSSEDRCPVCRQ 385
Cdd:cd16538    5 CSICLERLREPISLDCGHDFCIRCFSthRIPGCEPPCCPECRK 47

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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 328849261 344 ECPICR----EIAYKPVKMNCGHRFCVRCLVKLQKSSED---RCPVCRQCVV 388
Cdd:cd23140    3 ECSVCSegynEDERVPLLLQCGHTFCKDCLSQMFIRCTDltlKCPRCRQSVL 54

Uncharacterized conserved protein, contains RING Zn-finger [General function prediction only];

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 328849261 345 CPICREIAYKPVKMN-CGHRFCVRCLVKLQKSSEDRCPVC-RQCVVLDT-TPralELQTKVYMERWFPKEIKLK-TKDD 419
Cdd:COG5222  277 CPLCHCLLRNPMKTPcCGHTFCDECIGTALLDSDFKCPNCsRKDVLLDGlTP---DIDKKLEVEKALKKQRKKVgTSDD 352