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 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQQAVLL 264
Cdd:cd16527    3 CSLCLEERRHPTATPCGHLFCWSCITEWCNEKPECPLCREPFQPQRLVPL 52

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQQAVLL 264
Cdd:cd16527    3 CSLCLEERRHPTATPCGHLFCWSCITEWCNEKPECPLCREPFQPQRLVPL 52

Ring finger domain;

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                  ....*....|....*....|....*....|....*....|...
gi 215506034  214 SCCMC---VDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:pfam13639   2 ECPICleeFEEGDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

E3 ubiquitin-protein ligase RMA2; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 215506034 201 EDDDVDEARSPNYSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRA-------------KKE---CPLCR 253
Cdd:PLN03208   7 EDDTTLVDSGGDFDCNICLDQVRDPVVTLCGHLFCWPCIHKWTYAsnnsrqrvdqydhKREppkCPVCK 75

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQQAVLL 264
Cdd:cd16527    3 CSLCLEERRHPTATPCGHLFCWSCITEWCNEKPECPLCREPFQPQRLVPL 52

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 215506034 213 YSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRA---KKECPLCR 253
Cdd:cd16745    1 FECNICLDLAQDPVVTLCGHLFCWPCLHKWLRRqssQPECPVCK 44

RING finger, HC subclass, found in Saccharomyces cerevisiae increased recombination centers protein 20 (IRC20) and similar proteins; IRC20 is an uncharacterized ATP-dependent helicase that is probably involved in a pathway contributing to genomic integrity. IRC20 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 215506034 213 YSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd23135    4 LSCSICFSEIRSGAILKCGHFFCLSCIASWLREKSTCPLCK 44

RING finger, HC subclass, found in RING finger protein 5 (RNF5) and similar proteins; RNF5, also known as protein G16 or Ram1, is an E3 ubiquitin-protein ligase anchored to the outer membrane of the endoplasmic reticulum (ER). It acts at early stages of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) biosynthesis and functions as a target for therapeutic modalities to antagonize mutant CFTR proteins in CF patients carrying the F508del allele. It also regulates the turnover of specific G protein-coupled receptors by ubiquitinating JNK-associated membrane protein (JAMP) and preventing proteasome recruitment. RNF5 limits basal levels of autophagy and influences susceptibility to bacterial infection through the regulation of ATG4B stability. It is also involved in the degradation of Pendrin, a transmembrane chloride/anion exchanger highly expressed in thyroid, kidney, and inner ear. RNF5 plays an important role in cell adhesion and migration. It can modulate cell migration by ubiquitinating paxillin. Furthermore, RNF5 interacts with virus-induced signaling adaptor (VISA) at mitochondria in a viral infection-dependent manner, and further targets VISA at K362 and K461 for K48-linked ubiquitination and degradation after viral infection. It also negatively regulates virus-triggered signaling by targeting MITA, also known as STING, for ubiquitination and degradation at the mitochondria. In addition, RNF5 determines breast cancer response to ER stress-inducing chemotherapies through the regulation of the L-glutamine carrier proteins SLC1A5 and SLC38A2 (SLC1A5/38A2). It also has been implicated in muscle organization and in recognition and processing of misfolded proteins. RNF5 contains a C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....
gi 215506034 213 YSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRA---KKECPLCR 253
Cdd:cd16743    1 FECNICLETARDAVVSLCGHLFCWPCLHQWLETrpeRQECPVCK 44

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKE---CPLCRMQCE 257
Cdd:cd16611    6 HCPLCLDFFRDPVMLSCGHNFCQSCITGFWELQAEdttCPECRELCQ 52

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 215506034 213 YSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRA-KKECPLC 252
Cdd:cd16449    1 LECPICLERLKDPVLLPCGHVFCRECIRRLLESgSIKCPIC 41

Zinc finger, C3HC4 type (RING finger);

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                  ....*....|....*....|....*....|....*....
gi 215506034  215 CCMCVDGARRP-TVIPCGHVFCWYCIAGWLRAKKECPLC 252
Cdd:pfam13923   2 CPICMDMLKDPsTTTPCGHVFCQDCILRALRAGNECPLC 40

RING finger, HC subclass, found in RING finger protein 219 (RNF219) and similar proteins; RNF219 may function as a modulator of late-onset Alzheimer's disease (LOAD) associated amyloid beta A4 precursor protein (APP) endocytosis and metabolism. It genetically interacts with apolipoprotein E epsilon4 allele (APOE4). Thus, a genetic variant of RNF219 was found to affect amyloid deposition in human brain and LOAD age-of-onset. Moreover, common genetic variants at the RNF219 locus had been associated with alternations in lipid metabolism, cognitive performance and central nervous system ventricle volume. RNF219 contains a C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|
gi 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd16562    3 SCHICLGKVRQPVICSNNHVFCSSCMDVWLKNNNQCPACR 42

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

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 215506034  215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCRMqcePQQAVLLR 265
Cdd:TIGR00599  29 CHICKDFFDVPVLTSCSHTFCSLCIRRCLSNQPKCPLCRA---EDQESKLR 76

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.

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                 ....*....|....*....|....*....|....*....
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd16535    4 CSICSELFIEAVTLNCSHSFCSYCITEWMKRKKECPICR 42

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 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd16546    2 ECPICLQTCIHPVKLPCGHIFCYLCVKGVAWQSKRCALCR 41

RING finger, HC subclass, found in ligand of numb protein X 4 (LNX4); LNX4, also known as PDZ domain-containing RING finger protein 4 (PDZRN4), or SEMACAP3-like protein (SEMCAP3L), is an E3 ubiquitin-protein ligase responsible for the ubiquitination and degradation of Numb, a component of the Notch signaling pathway that functions in the specification of cell fates during development and is known to control cell numbers during neurogenesis in vertebrates. LNX4 contains an N-terminal C3HC4-type RING-HC finger, two PDZ domains, and a C-terminal LNX3 homology (LNX3H) domain.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 215506034 211 PNYSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLcrmQCEPQQA 261
Cdd:cd16719    3 PDLKCKLCGKVLEEPLSTPCGHVFCAGCLLPWAVQRRLCPL---QCQPIAA 50

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.

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                 ....*....|....*....|....*....|....*....|....*..
gi 215506034 212 NYSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEP 258
Cdd:cd16547    3 DLICSICHGVLRCPVRLSCSHIFCKKCILQWLKRQETCPCCRKEVKG 49

RING finger, HC subclass, found in Saccharomyces cerevisiae POB3/SPT16 histone-associated protein 1 (ScPSH1) and similar proteins; ScPSH1 is a Cse4-specific E3 ubiquitin ligase that interacts with the kinetochore protein Pat1 and targets the degradation of budding yeast centromeric histone H3 variant, CENP-ACse4, which is essential for faithful chromosome segregation. ScPSH1 contains a C3HC4-type RING-HC finger and a DNA directed RNA polymerase domain.

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                 ....*....|....*....|....*....|....*....|..
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKE--CPLCRM 254
Cdd:cd16568    7 CIICHEYLYEPMVTTCGHTYCYTCLNTWFKSNRSlsCPDCRT 48

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 215506034   215 CCMCVD-GARRPTVIPCGHVFCWYCIAGWLRAK-KECPLC 252
Cdd:smart00184   1 CPICLEeYLKDPVILPCGHTFCRSCIRKWLESGnNTCPIC 40

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 215506034 211 PNYSCCMCVDGARRP-TVIPCGHVFCWYCIAGWL-RAKKECPLCRMQCE 257
Cdd:cd16503    1 ENLTCSICQDLLHDCvSLQPCMHNFCAACYSDWMeRSNTECPTCRATVQ 49

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 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAG-WLRAKKE---CPLCRMqCEPQQAVLLRNVT 268
Cdd:cd16597    7 TCSICLELFKDPVTLPCGHNFCGVCIEKtWDSQHGSeysCPQCRA-TFPRRPELHKNTV 64

RING finger, HC subclass, found in topoisomerase I-binding arginine/serine-rich protein (Topors) and similar proteins; Topors, also known as topoisomerase I-binding RING finger protein, tumor suppressor p53- binding protein 3, or p53-binding protein 3 (p53BP3), is a ubiquitously expressed nuclear E3 ubiquitin-protein ligase that can ligate both ubiquitin and small ubiquitin-like modifier (SUMO) to substrate proteins in the nucleus. It contains an N-terminal C3HC4-type RING-HC finger which ligates ubiquitin to its target proteins including DNA topoisomerase I, p53, NKX3.1, H2AX, and the AAV-2 Rep78/68 proteins. As a RING-dependent E3 ubiquitin ligase, Topors works with the E2 enzymes UbcH5a, UbcH5c, and UbcH6, but not with UbcH7, CDC34, or UbcH2b. Topors acts as a tumor suppressor in various malignancies. It regulates p53 modification, suggesting it may be responsible for astrocyte elevated gene-1 (AEG-1, also known as metadherin, or LYRIC) ubiquitin modification. Plk1-mediated phosphorylation of Topors inhibits Topors-mediated sumoylation of p53, whereas p53 ubiquitination is enhanced, leading to p53 degradation. It also functions as a negative regulator of the prostate tumor suppressor NKX3.1. Moreover, Topors is associated with promyelocytic leukemia nuclear bodies, and may be involved in the cellular response to camptothecin. It also plays a key role in the turnover of H2AX protein, discriminating the type of DNA damaging stress. Furthermore, Topors is a cilia-centrosomal protein associated with autosomal dominant retinal degeneration. Mutations in TOPORS cause autosomal dominant retinitis pigmentosa (adRP).

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                 ....*....|....*....|....*....|....*....|..
gi 215506034 214 SCCMCVDGARRPTVI--PCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd16574    3 SCPICLDRFENEKAFldGCFHAFCFTCILEWSKVKNECPLCK 44

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

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                 ....*....|....*....|....*....|....*....|...
gi 215506034 213 YSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRA--KKECPLCR 253
Cdd:cd23132    3 FLCCICLDLLYKPVVLECGHVFCFWCVHRCMNGydESHCPLCR 45

RING finger, HC subclass, found in Equid alphaherpesvirus 1 (Equine herpesvirus 1/EHV-1) regulatory protein and similar proteins; EHV-1 regulatory protein belongs to the Vmw110 (IPC0) protein family. It contains a typical C3HC4-type RING-HC finger and binds zinc stably.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 215506034 214 SCCMCVDG-ARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd23130    2 VCPICLDDpEDEAITLPCLHQFCYTCILRWLQTSPTCPLCK 42

RING finger, HC subclass, found in ligand of numb protein X 3 (LNX3); LNX3, also known as PDZ domain-containing RING finger protein 3 (PDZRN3), or Semaphorin cytoplasmic domain-associated protein 3 (SEMACAP3), is an E3 ubiquitin-protein ligase that was first identified as a Semaphorin-binding partner. It is also responsible for the ubiquitination and degradation of Numb, a component of the Notch signaling pathway that functions in the specification of cell fates during development and is known to control cell numbers during neurogenesis in vertebrates. LNX3 acts as a negative regulator of osteoblast differentiation by inhibiting Wnt-beta-catenin signaling. LNX3 also plays an important role in neuromuscular junction formation. It interacts with and ubiquitinates the muscle specific tyrosine kinase (MuSK), thus promoting its endocytosis and negatively regulating the cell surface expression of this key regulator of postsynaptic assembly. LNX3 contains an N-terminal C3HC4-type RING-HC finger, two PDZ domains, and a C-terminal LNX3 homology (LNX3H) domain.

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                 ....*....|....*....|....*....|....*....|....
gi 215506034 211 PNYSCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPL-CR 253
Cdd:cd16718    3 PDFKCNLCNKVLEDPLTTPCGHVFCAGCVLPWVVQQGSCPVkCQ 46

RING finger, HC subclass, found in tripartite motif-containing protein 77 (TRIM77) and similar proteins; TRIM77 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 two consecutive zinc-binding domains, a C3HC4-type RING-HC finger and Bbox2, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 215506034 211 PNYSCCMCVDGARRPTVIPCGHVFCWYCIAG-WLRAKK--ECPLCRM 254
Cdd:cd16543    2 DQLTCSICLDLLKDPVTIPCGHSFCMNCITLlWDRKQGvpSCPQCRE 48

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 215506034 212 NYSCCMCVDGARRPTVI-PCGHVFCWYCIAGWLR-AKKECPLCRM 254
Cdd:cd16549    1 QFSCPICLEVYHKPVVItSCGHTFCGECLQPCLQvASPLCPLCRM 45

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 215506034 216 CMCVDGARRPTVI-PCGHVFCWYCIAGWLRAK-KECPLCR 253
Cdd:cd16448    4 CLEEFEEGDVVRLlPCGHVFHLACILRWLESGnNTCPLCR 43

RING finger, HC subclass, found in Saccharomyces cerevisiae radiation sensitivity protein 18 (RAD18) and similar proteins; RAD18, also called RING-type E3 ubiquitin transferase RAD18, acts as a postreplication repair E3 ubiquitin-protein ligase that associates with the E2 ubiquitin conjugating enzyme UBC2/RAD6 to form the UBC2-RAD18 ubiquitin ligase complex involved in postreplicative repair (PRR) of damaged DNA. The UBC2-RAD18 complex cooperates with RAD5 and the UBC13-MMS2 dimer to attach mono-ubiquitin chains on 'Lys-164' of POL30, which is necessary for PRR. The UBC2-RAD18 complex is also involved in prevention of spontaneous mutations caused by 7,8-dihydro-8-oxoguanine. RAD18 is an E3 RING-finger protein belonging to the UBC2/RAD6 epistasis group. It contains a typical C3HC4-type RING-HC finger.

                         10        20        30
                 ....*....|....*....|....*....|....*....
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd23148    6 CHICKDLLKAPMRTPCNHTFCSFCIRTHLNNDARCPLCK 44

RING finger, HC subclass, found in RING finger protein 10 (RNF10) and similar proteins; RNF10 is an E3 ubiquitin-protein ligase that interacts with mesenchyme Homeobox 2 (MEOX2) transcription factor, a regulator of the proliferation, differentiation and migration of vascular smooth muscle cells and cardiomyocytes; it enhances Meox2 activation of the p21 promoter. It also regulates the expression of myelin-associated glycoprotein (MAG) genes and is required for myelin production in Schwann cells of the peripheral nervous system. Moreover, RNF10 regulates retinoic acid-induced neuronal differentiation and the cell cycle exit of P19 embryonic carcinoma cells. RNF10 contains a C3HC4-type RING-HC finger and three putative nuclear localization signals.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 215506034 213 YSCCMCVDGARRPTVIPCGHVFCWYCIAGWL----RAKKECPLC 252
Cdd:cd16536    1 PQCPICLEPPVAPRITRCGHIFCWPCILRYLslseKKWRKCPIC 44

RING finger, HC subclass, found in tripartite motif-containing protein 39 (TRIM39) and similar proteins; TRIM39, also known as RING finger protein 23 (RNF23) or testis-abundant finger protein, is an E3 ubiquitin-protein ligase that plays a role in controlling DNA damage-induced apoptosis through inhibition of the anaphase promoting complex (APC/C), a multiprotein ubiquitin ligase that controls multiple cell cycle regulators, including cyclins, geminin, and others. TRIM39 also functions as a regulator of several key processes in the proliferative cycle. It directly regulates p53 stability. It modulates cell cycle progression and DNA damage responses via stabilizing p21. Moreover, TRIM39 negatively regulates the nuclear factor kappaB (NFkappaB)-mediated signaling pathway through stabilization of Cactin, an inhibitor of NFkappaB- and Toll-like receptor (TLR)-mediated transcription, which is induced by inflammatory stimulants such as tumor necrosis factor alpha. Furthermore, TRIM39 is a MOAP-1-binding protein that can promote apoptosis signaling through stabilization of MOAP-1 via the inhibition of its poly-ubiquitination process. TRIM39 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
                 ....*....|....*....|....*....|....*....|..
gi 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAGW---LRAKKECPLC 252
Cdd:cd16601    3 SCSLCKEYLKDPVIIECGHNFCRACITRFweeLDGDFPCPQC 44

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 215506034 215 CCMCVDGARRPTVIP-CGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd16506    3 CPICLDEIQNKKTLEkCKHSFCEDCIDRALQVKPVCPVCG 42

RING finger, HC subclass, found in polycomb group RING finger protein 1 (PCGF1) and similar proteins; PCGF1, also known as nervous system Polycomb-1 (NSPc1) or RING finger protein 68 (RNF68), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR). It serves as the core component of a noncanonical Polycomb repressive complex 1 (PRC1)-like BCOR complex that also contains RING1, RNF2, RYBP, SKP1, as well as the BCL6 co-repressor BCOR and the histone demethylase KDM2B, and is required to maintain the transcriptionally repressive state of some genes, such as Hox genes, BCL6 and the cyclin-dependent kinase inhibitor, CDKN1A. PCGF1 promotes cell cycle progression and enhances cell proliferation as well. It is a cell growth regulator that acts as a transcriptional repressor of p21Waf1/Cip1 via the retinoid acid response element (RARE element). Moreover, PCGF1 functions as an epigenetic regulator involved in hematopoietic cell differentiation. It cooperates with the transcription factor runt-related transcription factor 1 (Runx1) in regulating differentiation and self-renewal of hematopoietic cells. Furthermore, PCGF1 represents a physical and functional link between Polycomb function and pluripotency. PCGF1 contains a C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 215506034 210 SPNYSCCMC----VDGArrpTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQQAVL 263
Cdd:cd16733    7 NEHIVCYLCagyfIDAT---TITECLHTFCKSCIVKYLQTSKYCPMCNIKIHETQPLL 61

RING finger, HC subclass, found in RING finger protein 220 (RNF220) and similar proteins; RNF220 is an E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of Sin3B, a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. It can also bind E2 and mediate auto-ubiquitination of itself. Moreover, RNF220 specifically interacts with beta-catenin, and enhances canonical Wnt signaling through ubiquitin-specific protease 7 (USP7)-mediated deubiquitination and stabilization of beta-catenin, which is independent of its E3 ligase activity. RNF220 contains a characteristic C3HC4-type RING-HC finger at its C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 215506034 213 YSCCMCVDGARRPTV-IPCGHVFCWYCiagWLR---AKKECPLCRMQCEPQ 259
Cdd:cd16563    1 YKCLICMDSYTMPLVsIQCWHVHCEEC---WLRtlgAKKLCPQCNTITSPA 48

RING finger, HC subclass, found in Ret finger protein-like 4B (RFPL4B) and similar proteins; RFPL4B, also called RING finger protein 211 (RNF211), is an uncharacterized RING finger protein containing a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKE----CPLCR 253
Cdd:cd16623   10 TCPICLDFFSHPISLSCAHIFCFDCIQKWMTKREDsiltCPLCR 53

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 215506034 225 PTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQQAVLLR 265
Cdd:cd16451   14 TALATSGYVFCYPCIYRYVKEHGRCPVTGYPASLDHLIKLY 54

RING finger, H2 subclass, found in RING finger protein 111 (RNF111) and similar proteins; RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It acts as an amplifier of Nodal signals, and enhances the dorsalizing activity of limiting amounts of Xnr1, a Nodal homolog, and requires Nodal signaling for its function. The loss of RNF111 results in early embryonic lethality, with defects attributed to compromised Nodal signaling. RNF111 also regulates tumor metastasis by modulation of the TGF-beta pathway. Its ubiquitination can be modulated by the four and a half LIM-only protein 2 (FHL2) that activates TGF-beta signal transduction. Furthermore, RNF111 interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. In addition, RNF111 has been identified as a small ubiquitin-like modifier (SUMO)-binding protein with clustered SUMO-interacting motifs (SIMs) that together form a SUMO-binding domain (SBD). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). The N-terminal half of RNF111 harbors three SIMs. Its C-terminal half show high sequence similarity with RING finger protein 165 (RNF165), where it contains two serine rich domains, two nuclear localization signals, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is required for polyubiqutination and proteasome-dependent degradation of phosphorylated forms of Smad2/3 and three major negative regulators of TGF-beta signaling, Smad7, SnoN and c-Ski.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 215506034 202 DDDVDEarspnySCCMCV------DGARRptvIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQ 259
Cdd:cd16681    6 EEDTEE------KCTICLsileegEDVRR---LPCMHLFHQVCVDQWLITNKKCPICRVDIEAQ 60

RING finger, HC subclass, found in tripartite motif-containing proteins, TRIM7, TRIM11 and TRIM27, and similar proteins; TRIM7, TRIM11 and TRIM27, closely related tripartite motif-containing proteins, belong to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) by mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. TRIM11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM27, also known as RING finger protein 76 (RNF76), RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. In addition, it inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. TRIM27 promotes a non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. TRIM27 also forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is a component of an estrogen receptor 1 (ESR1) regulatory complex that is involved in estrogen receptor-mediated transcription in MCF-7 cells.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAG-WLRAKKE--CPLCRMQCEP 258
Cdd:cd16594    7 TCPICLDYFTDPVTLDCGHSFCRACIARcWEEPETSasCPQCRETCPQ 54

RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 215506034 207 EARSPNYSCCMCV-------DGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:cd23117    1 ENGSVDCVICMSDielpstnSVRRDYMVTPCNHIFHTNCLERWMDIKLECPTCR 54

RING finger, HC subclass, found in peroxin-2 (PEX2) and similar proteins; PEX2, also known as peroxisome biogenesis factor 2, 35 kDa peroxisomal membrane protein, peroxisomal membrane protein 3, peroxisome assembly factor 1 (PAF-1), or RING finger protein 72 (RNF72), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It may be involved in the biogenesis of peroxisomes, as well as in peroxisomal matrix protein import. Mutations in the PEX2 gene are the primary defect in a subset of patients with Zellweger syndrome and related peroxisome biogenesis disorders. Moreover, PEX2 functions as an E3-ubiquitin ligase that mediates the UBC4-dependent polyubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 215506034 215 CCMC-VDGARRPTVIPCGHVFCWYCIAGWLRAKK--ECPLC 252
Cdd:cd16526    4 CAICgEWPTNNPYSTGCGHVYCYYCIKSNLLADDsfTCPRC 44

N1R/p28-like protein; Provisional

                         10        20
                 ....*....|....*....|....
gi 215506034 230 CGHVFCWYCIAGWLRAKKECPLCR 253
Cdd:PHA02929 200 CNHVFCIECIDIWKKEKNTCPVCR 223

Zinc finger, C3HC4 type (RING finger); The C3HC4 type zinc-finger (RING finger) is a cysteine-rich domain of 40 to 60 residues that coordinates two zinc ions, and has the consensus sequence: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C where X is any amino acid. Many proteins containing a RING finger play a key role in the ubiquitination pathway.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 215506034  215 CCMCVDGARRPTVI-PCGHVFCWYCIAGWLRAKKE-CPLC 252
Cdd:pfam00097   1 CPICLEEPKDPVTLlPCGHLFCSKCIRSWLESGNVtCPLC 40

RING finger, H2 subclass, found in RING finger protein 130 (RNF130) and similar proteins; RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL). It is a transmembrane E3 ubiquitin-protein ligase expressed in leukocytes. It has a self-ubiquitination property, and controls the development of T cell clonal anergy by ubiquitination. RNF130 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 215506034 215 CCMCVDGARRPTVI---PCGHVFCWYCIAGWLRAKKECPLCRM 254
Cdd:cd16803    3 CAVCIEGYKQNDVVrilPCKHVFHKSCVDPWLNEHCTCPMCKL 45

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl and similar proteins; Cbl, also known as Casitas B-lineage lymphoma proto-oncogene, proto-oncogene c-Cbl, RING finger protein 55 (RNF55), or signal transduction protein Cbl, is a multi-domain protein that acts as a key negative regulator of various receptor and non-receptor tyrosine kinase signaling. It contains a tyrosine kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain), a proline-rich domain, a C3HC4-type RING-HC finger, and an ubiquitin-associated (UBA) domain. TKB is responsible for the interactions with many tyrosine kinases, such as the colony-stimulating factor-1 (CSF-1) receptor, Syk/ZAP-70, and Src-family of protein tyrosine kinases. The proline-rich domain can recruit proteins with a SH3 domain. Moreover, Cbl functions as an E3 ubiquitin ligase that can bind ubiquitin-conjugating enzymes (E2s) through the RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKE-CPLCRMQCEPQQAVLL 264
Cdd:cd16708   24 CKICAENDKDVKIEPCGHLMCTSCLTSWQESEGQgCPFCRCEIKGTEPIVV 74

RING finger, HC subclass, found in Arabidopsis thaliana BRCA1-associated RING domain protein 1 (AtBARD1) and similar proteins; AtBARD1, also called protein REPRESSOR OF WUSCHEL 1, binds specifically to H3K4me3 regions of target gene (e.g. WUS and WOX5) promoters to repress their transcription via chromatin remodeling. It is required for the shoot apical meristem (SAM) organization and maintenance, by confining WUS expression to the organizing center, and for the quiescent center (QC) development in the root apical meristem (RAM), by repressing WOX5 expression in the root proximal meristem. AtBARD1 plays a role in DNA repair and in cell-cycle control. It is required for the repair of DNA double-strand breaks (DSBs), both natural and induced by genotoxic stress, by homologous recombination (HR). AtBARD1 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLCRMQCEPQ 259
Cdd:cd23146    7 CPICLKLLNRPVLLPCDHIFCSSCITDSTKVGSDCPVCKLPYHSQ 51

RING finger, HC subclass, found in ligand of Numb protein LNX3, LNX4, and similar proteins; The ligand of Numb protein X (LNX) family, also known as PDZ and RING (PDZRN) family, includes LNX1-5, which can interact with Numb, a key regulator of neurogenesis and neuronal differentiation. LNX5 (also known as PDZK4, or PDZRN4L) shows high sequence homology to LNX3 and LNX4, but it lacks the RING domain. LNX1-4 proteins function as E3 ubiquitin ligases and have a unique domain architecture consisting of an N-terminal RING-HC finger for E3 ubiquitin ligase activity and either two or four PDZ domains necessary for the substrate-binding. This family corresponds to LNX3/LNX4-like proteins, which contains a C3HC4-type RING-HC finger and two PDZ domains.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 215506034 215 CCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKECPLcrmQCEP 258
Cdd:cd16512    3 CKLCLGVLEEPLATPCGHVFCAGCVLPWVVRNGSCPL---KCEP 43

RING finger, HC subclass, found in tripartite motif-containing protein 68 (TRIM68) and similar proteins; TRIM68, also known as RING finger protein 137 (RNF137) or SSA protein SS-56 (SS-56), is an E3 ubiquitin-protein ligase that negatively regulates Toll-like receptor (TLR)- and RIG-I-like receptor (RLR)-driven type I interferon production by degrading TRK fused gene (TFG), a novel driver of IFN-beta downstream of anti-viral detection systems. It also functions as a cofactor for androgen receptor-mediated transcription by regulating ligand-dependent transcription of androgen receptor in prostate cancer cells. Moreover, TRIM68 is a cellular target of autoantibody responses in Sjogre's syndrome (SS), as well as systemic lupus erythematosus (SLE). It is also an auto-antigen for T cells in SS and SLE. TRIM68 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 215506034 214 SCCMCVDGARRPTVIPCGHVFCWYCIAGWLRAKKE-------CPLCR 253
Cdd:cd16610    3 ACPICMTFLREPVSIDCGHSFCHSCLSGLWEVPGEsqnwgytCPLCR 49