Roquin II domain; The ROQ domain is composed of three subdomains, I, II and III. This entry describes the second domain, ROQ II. Structural analysis reveals similarity of domain II to the helix-turn-helix (HTH) fold. Mutagenesis and biochemical studies show that that the HTH fold in domain II contributes to binding dsRNA at the 5'arm.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*.
gi 664806080   271 EEFRTYEALRREHDSQIVQIAMEAGLRIAPDQWSSLLYGDQSHKSHMQSIIDKLQT 326
Cdd:pfam18386    1 DEFRSYEALRREHDAQIVQIAFEYGLRISPEQWSALLYGDQAHRSHMQSIIDKLQS 56

Zinc finger C-x8-C-x5-C-x3-H type (and similar);

                           10        20
                   ....*....|....*....|....*..
gi 664806080   414 YKTYMCRDMKQRGGCPRGASCTFAHSQ 440
Cdd:pfam00642    1 YKTELCRFFLRTGYCKYGDRCKFAHGQ 27

Roquin II domain; The ROQ domain is composed of three subdomains, I, II and III. This entry describes the second domain, ROQ II. Structural analysis reveals similarity of domain II to the helix-turn-helix (HTH) fold. Mutagenesis and biochemical studies show that that the HTH fold in domain II contributes to binding dsRNA at the 5'arm.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*.
gi 664806080   271 EEFRTYEALRREHDSQIVQIAMEAGLRIAPDQWSSLLYGDQSHKSHMQSIIDKLQT 326
Cdd:pfam18386    1 DEFRSYEALRREHDAQIVQIAFEYGLRISPEQWSALLYGDQAHRSHMQSIIDKLQS 56

zinc-RING finger domain;

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|...
gi 664806080    14 CPICTQTFDETiRKPISLGCGHTVCKMCLNKLHRKA-CPFDQT 55
Cdd:pfam14634    2 CNKCFKELSKT-RPFYLTSCGHIFCEECLTRLLQERqCPICKK 43

Zinc finger C-x8-C-x5-C-x3-H type (and similar);

                           10        20
                   ....*....|....*....|....*..
gi 664806080   414 YKTYMCRDMKQRGGCPRGASCTFAHSQ 440
Cdd:pfam00642    1 YKTELCRFFLRTGYCKYGDRCKFAHGQ 27

Roquin II domain; The ROQ domain is composed of three subdomains, I, II and III. This entry describes the second domain, ROQ II. Structural analysis reveals similarity of domain II to the helix-turn-helix (HTH) fold. Mutagenesis and biochemical studies show that that the HTH fold in domain II contributes to binding dsRNA at the 5'arm.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*.
gi 664806080   271 EEFRTYEALRREHDSQIVQIAMEAGLRIAPDQWSSLLYGDQSHKSHMQSIIDKLQT 326
Cdd:pfam18386    1 DEFRSYEALRREHDAQIVQIAFEYGLRISPEQWSALLYGDQAHRSHMQSIIDKLQS 56

Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-2; Roquin-2, also known as membrane-associated nucleic acid-binding protein (MNAB), RING finger and CCCH-type zinc finger domain-containing protein 2 (RC3H2), or RING finger protein 164 (RNF164), is an E3 ubiquitin ligase that is localized to the cytoplasm and upon stress, is concentrated in stress granules. It is required for reactive oxygen species (ROS)-induced ubiquitination and degradation of apoptosis signal-regulating kinase 1 (ASK1, also known as MAP3K5). Roquin-2 interacts with the 3'UTR of tumor necrosis factor receptor superfamily member 4 (TNFRSF4) and tumor-necrosis factor-alpha (TNFalpha), and modulates immune responses. Moreover, Roquin-2 shares functions with its paralog Roquin-1 in the repression of mRNAs controlling T follicular helper cells and systemic inflammation. Roquin-2 contains an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 ubiquitin-ligase function, a highly conserved ROQ domain required for RNA binding and localization to stress granules, a coiled-coil (CC1), and a CCCH-type zinc finger that is involved in RNA recognition.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 664806080    7 QWTDFLSCPICTQTFDETIRKPISLGCGHTVCKMCLNKLHRKACPFDQT 55
Cdd:cd16782     1 QWTEFLSCPICYNEFDENVHKPISLGCSHTVCKTCLNKLHRKACPFDQT 49

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 664806080   12 LSCPICTQTFDEtirkPISLGCGHTVCKMCLNKL---HRKACPFD 53
Cdd:cd16449     1 LECPICLERLKD----PVLLPCGHVFCRECIRRLlesGSIKCPIC 41

first RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the first RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 664806080   10 DFLSCPICTQTFDEtirkPISLGCGHTVCKMCLNKLHRKAC 50
Cdd:cd16513     1 DLLSCPLCRGLLFE----PVTLPCGHTFCKRCLERDPSSRC 37

zinc-RING finger domain;

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|...
gi 664806080    14 CPICTQTFDETiRKPISLGCGHTVCKMCLNKLHRKA-CPFDQT 55
Cdd:pfam14634    2 CNKCFKELSKT-RPFYLTSCGHIFCEECLTRLLQERqCPICKK 43

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 664806080   12 LSCPICTQTFDETIRKPISLGCGHTVCKMCLNKLH--------RKACPF 52
Cdd:cd16555     2 LECKICYNRYDLRQRRPKVLECCHRVCAKCLYKIVdlgdsspsVLVCPF 50

DNA translocase FtsK; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 664806080  494 PNGIVSTGNTVTQLIPRGTDPSYDSSLKPGkidhlSSSAPGSPPDLLESVPKSISALPV---NPHSIPPRGPADLPPMPV 570
Cdd:PRK10263  319 PVAVAAAATTATQSWAAPVEPVTQTPPVAS-----VDVPPAQPTVAWQPVPGPQTGEPViapAPEGYPQQSQYAQPAVQY 393

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 664806080  571 TKPLQMVPRGSQLYPAQQTDVYYQDPRGAAPPFEPAPYQQGMYYTPPPQCVSRFVRPPPSAPEPAPPYLDHYPPYlQERV 650
Cdd:PRK10263  394 NEPLQQPVQPQQPYYAPAAEQPAQQPYYAPAPEQPAQQPYYAPAPEQPVAGNAWQAEEQQSTFAPQSTYQTEQTY-QQPA 472

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 664806080  651 VNSQYGTQPQQYPPiypshydgrrvypaPSYTREEifresPIPIEIPPAAVPSY----VPESRER-YQQIESYYPVAPHP 725
Cdd:PRK10263  473 AQEPLYQQPQPVEQ--------------QPVVEPE-----PVVEETKPARPPLYyfeeVEEKRAReREQLAAWYQPIPEP 533

                  ..
gi 664806080  726 TQ 727
Cdd:PRK10263  534 VK 535

RING finger, HC subclass, found in tripartite motif-containing protein 47 (TRIM47) and similar proteins; TRIM47, also known as gene overexpressed in astrocytoma protein (GOA) or RING finger protein 100 (RNF100), 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, 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. It plays an important role in the process of dedifferentiation that is associated with astrocytoma tumorigenesis. This subfamily also includes RING finger protein 135 (RNF135). RNF135, also known as RIG-I E3 ubiquitin ligase (REUL) or Riplet, is a widely expressed E3 ubiquitin-protein ligase that consists of an N-terminal C3HC4-type RING-HC finger and C-terminal B30.2/SPRY and PRY motifs, but lacks the B-box and coiled-coil domains that are also typically present in TRIM proteins. RNF135 serves as a specific retinoic acid-inducible gene-I (RIG-I)-interacting protein that ubiquitinates RIG-I and specifically stimulates RIG-I-mediated innate antiviral activity to produce antiviral type-I interferon (IFN) during the early phase of viral infection. It also has been identified as a bio-marker and therapy target of glioblastoma. It associates with the ERK signal transduction pathway and plays a role in glioblastoma cell proliferation, migration and cell cycle.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 664806080   12 LSCPICTqtfdETIRKPISLGCGHTVCKMCLNKL------HRKACPFDQTT 56
Cdd:cd16604     1 LSCPICL----DLLKDPVTLPCGHSFCMGCLGALwgagrgGRASCPLCRQT 47

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.

                          10        20        30
                  ....*....|....*....|....*....|...
gi 664806080   12 LSCPICTQTFDEtirkPISLGCGHTVCKMCLNK 44
Cdd:cd16597     6 LTCSICLELFKD----PVTLPCGHNFCGVCIEK 34

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
                  ....*....|....*....|....*....|....*...
gi 664806080   14 CPICTQTFdetiRKPISLGCGHTVCKMCLNKLHRKACP 51
Cdd:cd16602     6 CAICLDYF----KDPVSIGCGHNFCRVCVTQLWGFTCP 39

RING finger, HC subclass, found in tripartite motif-containing protein 35 (TRIM35) and similar proteins; TRIM35, also known as hemopoietic lineage switch protein 5 (HLS5), is a putative hepatocellular carcinoma (HCC) suppressor that inhibits phosphorylation of pyruvate kinase isoform M2 (PKM2), which is involved in aerobic glycolysis of cancer cells and further suppresses the Warburg effect and tumorigenicity in HCC. It also negatively regulates Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon production by suppressing the stability of interferon regulatory factor 7 (IRF7). Moreover, TRIM35 regulates erythroid differentiation by modulating globin transcription factor 1 (GATA-1) activity. TRIM35 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 664806080   12 LSCPICTQTFdetiRKPISLGCGHTVCKMCLNK----LHRKACPFDQTTINTDIelLPVNSALLQLV 74
Cdd:cd16599     5 LLCPICYEPF----REAVTLRCGHNFCKGCVSRswerQPRAPCPVCKEASSSDD--LRTNHTLNNLV 65

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

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 664806080   10 DFLSCPICTQTFDEtirkPISLGCGHTVCKMCLNKL 45
Cdd:cd16581     1 EELTCSICYNIFDD----PKILPCSHTFCKNCLEKL 32

Modified RING finger, HC subclass (C3HC3D-type), found in uncharacterized proteins similar to tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4); This subfamily corresponds to a group of uncharacterized proteins that shows high sequence similarity with tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4). TRAF4, also known as cysteine-rich domain associated with RING and Traf domains protein 1, or metastatic lymph node gene 62 protein (MLN 62), or RING finger protein 83 (RNF83), is a member of TRAF protein family, which mainly function in the immune system, where they mediate signaling through tumor necrosis factor receptors (TNFRs) and interleukin-1/Toll-like receptors (IL-1/TLRs). It also plays a critical role in the nervous system, as well as in carcinogenesis. Like TRAF4, members of this subfamily contain a modified C3HC3D-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 664806080   14 CPICtqtfDETIRKPISLG-CGHTVCKMCLNKLHRKA--CPFDQTTINTD 60
Cdd:cd23126     7 CPVC----CQVLRYPVQFEeCGHRVCSSCLPELLRVEprCPIDQGPIDRD 52

Zinc finger C-x8-C-x5-C-x3-H type (and similar);

                           10        20
                   ....*....|....*....|....*..
gi 664806080   414 YKTYMCRDMKQRGGCPRGASCTFAHSQ 440
Cdd:pfam00642    1 YKTELCRFFLRTGYCKYGDRCKFAHGQ 27

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.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....
gi 664806080    14 CPICTQTFDetirKPISLGCGHTVCKMCLNKLHRKA------CP 51
Cdd:pfam15227    1 CPICLDYLE----KPVSIECGHSFCLSCINSLQKEPdgesllCP 40

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
                  ....*....|....*....|....*....|....
gi 664806080   12 LSCPICtQTFdetIRKPISLGCGHTVCKMCLNKL 45
Cdd:cd16610     2 VACPIC-MTF---LREPVSIDCGHSFCHSCLSGL 31

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 664806080   12 LSCPICTQTFDEtirkPISLGCGHTVCKMCLNK--LHRKACP 51
Cdd:cd16504     3 FLCPICFDIIKE----AFVTKCGHSFCYKCIVKhlEQKNRCP 40

RING finger, HC subclass, found in tripartite motif-containing protein 62 (TRIM62) and similar proteins; TRIM62, also known as Ductal Epithelium Associated Ring Chromosome 1 (DEAR1), is a cytoplasmic E3 ubiquitin-protein ligase that was identified as a dominant regulator of acinar morphogenesis in the mammary gland. It is implicated in the inflammatory response of immune cells by regulating the Toll-like receptor 4 (TLR4) signaling pathway, leading to increased activity of the activator protein 1 (AP-1) transcription factor in primary macrophages. It is also involved in muscular protein homeostasis, especially during inflammation-induced atrophy, and may play a role in the pathogenesis of ICU-acquired weakness (ICUAW) by activating and maintaining inflammation in myocytes. Moreover, TRIM62 facilitates K27-linked poly-ubiquitination of CARD9 and also regulates CARD9-mediated anti-fungal immunity and intestinal inflammation. It also functions as a chromosome 1p35 tumor suppressor and negatively regulates transforming growth factor beta (TGFbeta)-driven epithelial-mesenchymal transition (EMT) by binding to and promoting the ubiquitination of SMAD3, a major effector of TGFbeta-mediated EMT. TRIM62 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 664806080    9 TDFLSCPICTQTFdetiRKPISLGCGHTVCKMCLN 43
Cdd:cd16608     4 KDELLCSICLSIY----QDPVSLGCEHYFCRQCIT 34

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 664806080   13 SCPICTQTFDetiRKPISLGCGHTVCKMCLNKL---HRKACP 51
Cdd:cd16564     2 ECPVCYEDFD---DAPRILSCGHSFCEDCLVKQlvsMTISCP 40

Modified RING finger, HC subclass (C3HC3D-type), found in tripartite motif-containing protein 23 (TRIM23) and similar proteins; TRIM23, also known as ADP-ribosylation factor domain-containing protein 1, GTP-binding protein ARD-1, or RING finger protein 46 (RNF46), is an E3 ubiquitin-protein ligase belonging to the C-IX subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a modified C3HC3D-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as C-terminal ADP ribosylation factor (ARF) domains. TRIM23 is involved in nuclear factor (NF)-kappaB activation. It mediates atypical lysine 27 (K27)-linked polyubiquitin conjugation to NF-kappaB essential modulator NEMO, also known as IKKgamma, which plays an important role in the NF-kappaB pathway, and this conjugation is essential for TLR3- and RIG-I/MDA5-mediated antiviral innate and inflammatory responses. It also regulates adipocyte differentiation via stabilization of the adipogenic activator peroxisome proliferator-activated receptor gamma (PPARgamma) through atypical ubiquitin conjugation to PPARgamma. Moreover, TRIM23 interacts with and polyubiquitinates yellow fever virus (YFV) NS5 to promote its binding to STAT2 and trigger type I interferon (IFN-I) signaling inhibition.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 664806080   12 LSCPICTQTFDETIRK-PISLGCGHTVCKMCLNKLHRKA----CPFDQT 55
Cdd:cd16645     2 LECGVCEDVFSLQGDKvPRLLLCGHTVCHDCLTRLPLHGravrCPFDRQ 50

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 664806080   12 LSCPICTQTFDEtirkPISLGCGHTVCKMCLNKL 45
Cdd:cd16605     1 LLCPICLEVFKE----PLMLQCGHSYCKSCLVSL 30

RING finger, HC subclass, found in RING finger protein 186 (RNF186) and similar proteins; RNF186 is an E3 ubiquitin-protein ligase with an N-terminal C3HC4-type RING-HC finger and two putative C-terminal transmembrane domains which enable it to localize in a certain organelle. It regulates RING-dependent self-ubiquitination, as well as endoplasmic reticulum (ER) stress-mediated apoptosis through interaction with the Bcl-2 family protein BNip1.

                          10        20        30
                  ....*....|....*....|....*....|.
gi 664806080   12 LSCPICTQTFDETIRKPISLGCGHTVCKMCL 42
Cdd:cd16557     2 LECLVCRNPYSCFVRKPKLLACQHAFCAICL 32

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 664806080   13 SCPICTqtfdETIRKPISLGCGHTVCKMCLNKLHRK---ACP 51
Cdd:cd23137     4 ACPICM----NVAWKPVRLECSHVFCLRCLVKAQKQkkdNCP 41

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

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                  ....*....|....*....|....*....|.
gi 664806080   12 LSCPICTQTFdetiRKPISLGCGHTVCKMCL 42
Cdd:cd16594     6 LTCPICLDYF----TDPVTLDCGHSFCRACI 32

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 664806080   12 LSCPICTQtfdeTIRKPISLGCGHTVCKMCLN--KLHRKACPFDQTTINTD 60
Cdd:cd16546     1 PECPICLQ----TCIHPVKLPCGHIFCYLCVKgvAWQSKRCALCRQEIPED 47

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.

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                  ....*....|....*....|....*....|..
gi 664806080   12 LSCPICTqtfdETIRKPISLGCGHTVCKMCLN 43
Cdd:cd16601     2 ASCSLCK----EYLKDPVIIECGHNFCRACIT 29

Modified RING finger, HC subclass (C3HC3D-type), found in PHD and RING finger domain-containing protein 1 (PHRF1) and similar proteins; PHRF1, also known as KIAA1542, or CTD-binding SR-like protein rA9, is a ubiquitin ligase which induces the ubiquitination of TGIF (TG-interacting factor) at lysine 130. It acts as a tumor suppressor that promotes the transforming growth factor (TGF)-beta cytostatic program through selective release of TGIF-driven promyelocytic leukemia protein (PML) inactivation. PHRF1 contains a plant homeodomain (PHD) finger and a modified C3HC3D-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*..
gi 664806080   13 SCPICTQTF-DETIRKPISlgCGHTVCKMCLNKLHRKA--CPFDQTT 56
Cdd:cd16635     6 SCPICLNTFrDQAVGTPES--CDHIFCLDCILEWSKNAntCPVDRIV 50

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 664806080   12 LSCPICTQTFDetirKPISLGCGHTVCKMCLNKLHRKACP 51
Cdd:cd16540     2 FTCPVCLEIFE----TPVRVPCGHVFCNACLQECLKPKKP 37

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.

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                  ....*....|....*....|....*....|....*.
gi 664806080   13 SCPICTQTFDEtirkPISLGCGHTVCKMCLNKLHRK 48
Cdd:cd16621     2 SCPVCSDYLEK----PVSLECGYACCLQCLNSLQKE 33

RING finger, HC subclass, found in malin and similar proteins; Malin ("mal" for seizure in French), also known as NHL repeat-containing protein 1 (NHLRC1), or EPM2B, is a nuclear E3 ubiquitin-protein ligase that ubiquitinates and promotes the degradation of laforin (EPM2A encoding protein phosphatase). Malin and laforin operate as a functional complex that play key roles in regulating cellular functions such as glycogen metabolism, unfolded cellular stress response, and proteolytic processes. They act as pro-survival factors that negatively regulate the Hipk2-p53 cell death pathway. They also negatively regulate cellular glucose uptake by preventing plasma membrane targeting of glucose transporters. Moreover, they degrade polyglucosan bodies in concert with glycogen debranching enzyme and brain isoform glycogen phosphorylase. Furthermore, they, together with Hsp70, form a new functional complex that suppress the cellular toxicity of misfolded proteins by promoting their degradation through the ubiquitin-proteasome system. Defects in either malin or laforin may cause Lafora disease (LD), a fatal form of teenage-onset autosomal recessive progressive myoclonus epilepsy. In addition, malin may have function, independent of laforin, in lysosomal biogenesis and/or lysosomal glycogen disposal. Malin contains six NHL-repeat protein-protein interaction domains and a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*..
gi 664806080   12 LSCPICTQTFDETI-RKPISLGCGHTVCKMCLNKLHRKA-----CPF 52
Cdd:cd16516     1 LECKVCFEKYSHQQeHRPRNLPCGHVLCRECVTALAHPRrskleCPF 47

zinc finger;

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                    ....*....|....*....|....*..
gi 664806080    413 KYKTYMCRDMKqRGGCPRGASCTFAHS 439
Cdd:smart00356    1 KYKTELCKFFK-RGYCPRGDRCKFAHP 26

RING finger, HC subclass, found in Arabidopsis thaliana protein BREAST CANCER SUSCEPTIBILITY 1 homolog (AtBRCA1) and similar proteins; AtBRCA1 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). AtBRCA1 contains a typical C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|..
gi 664806080   12 LSCPICTQTFdetiRKPISLGCGHTVCKMCLNK--LHRKACP 51
Cdd:cd23147     5 LKCPICLSLF----KSAANLSCNHCFCAGCIGEslKLSAICP 42

RING finger, HC subclass, found in tripartite motif-containing protein 38 (TRIM38) and similar proteins; TRIM38, also known as RING finger protein 15 (RNF15) or zinc finger protein RoRet, is an E3 ubiquitin-protein ligase that promotes K63- and K48-linked ubiquitination of cellular proteins and also catalyzes self-ubiquitination. It negatively regulates Tumor necrosis factor alpha (TNF-alpha)- and interleukin-1beta-triggered Nuclear factor-kappaB (NF-kappaB) activation by mediating lysosomal-dependent degradation of transforming growth factor beta (TGFbeta)-activated kinase 1 (TAK1)-binding protein (TAB)2/3, two critical components of the TAK1 kinase complex. It also inhibits TLR3/4-mediated activation of NF-kappaB and interferon regulatory factor 3 (IRF3) by mediating ubiquitin-proteasomal degradation of TNF receptor-associated factor 6 (Traf6) and NAK-associated protein 1 (Nap1), respectively. Moreover, TRIM38 negatively regulates TLR3-mediated interferon beta (IFN-beta) signaling by targeting ubiquitin-proteasomal degradation of TIR domain-containing adaptor inducing IFN-beta (TRIF). It functions as a valid target for autoantibodies in primary Sjogren's Syndrome. TRIM38 belongs the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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                  ....*....|....*....|....*....|
gi 664806080   13 SCPICTQTFDEtirkPISLGCGHTVCKMCL 42
Cdd:cd16600     7 TCSICLQLMTE----PVSINCGHSYCKRCI 32

RING finger, HC subclass, found in postreplication repair protein RAD18 and similar proteins; RAD18, also known as HR18 or RING finger protein 73 (RNF73), is an E3 ubiquitin-protein ligase involved in post replication repair of UV-damaged DNA via its recruitment to stalled replication forks. It associates to the E2 ubiquitin conjugating enzyme UBE2B to form the UBE2B-RAD18 ubiquitin ligase complex involved in mono-ubiquitination of DNA-associated PCNA on K164. It also interacts with another E2 ubiquitin conjugating enzyme RAD6 to form a complex that monoubiquitinates proliferating cell nuclear antigen at stalled replication forks in DNA translesion synthesis. Moreover, Rad18 is a key factor in double-strand break DNA damage response (DDR) pathways via its association with K63-linked polyubiquitylated chromatin proteins. It can function as a mediator for DNA damage response signals to activate the G2/M checkpoint in order to maintain genome integrity and cell survival after ionizing radiation (IR) exposure. RAD18 contains a C3HC4-type RING-HC finger, a ubiquitin-binding zinc finger domain (UBZ), a SAP (SAF-A/B, Acinus and PIAS) domain, and a RAD6-binding domain (R6BD).

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                  ....*....|....*....|....*....|....*....|....*
gi 664806080    9 TDFLSCPICTQTFDETirkPISLGCGHTVCKMCLNK--LHRKACP 51
Cdd:cd16529     2 DDLLRCPICFEYFNTA---MMITQCSHNYCSLCIRRflSYKTQCP 43

RING finger, HC subclass, found in yeast Bre1 and its homologs from eukaryotes; Bre1 is an E3 ubiquitin-protein ligase that catalyzes monoubiquitination of histone H2B in concert with the E2 ubiquitin-conjugating enzyme, Rad6. The Rad6-Bre1-mediated histone H2B ubiquitylation modulates the formation of double-strand breaks (DSBs) during meiosis in yeast. it is also required, indirectly, for the methylation of histone 3 on lysine 4 (H3K4) and 79. RNF20, also known as BRE1A and RNF40, also known as BRE1B, are the mammalian homologs of Bre1. They work together to form a heterodimeric Bre1 complex that facilitate the K120 monoubiquitination of histone H2B (H2Bub1), a DNA damage-induced histone modification that is crucial for recruitment of the chromatin remodeler SNF2h to DNA double-strand break (DSB) damage sites. Moreover, the Bre1 complex acts as a tumor suppressor, augmenting expression of select tumor suppressor genes and suppressing select oncogenes. Deficiency in the mammalian histone H2B ubiquitin ligase Bre1 leads to replication stress and chromosomal instability. All subfamily members contain a C3HC4-type RING-HC finger at its C-terminus.

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                  ....*....|....*....|....*....|....*....|....
gi 664806080   12 LSCPICTQTFDETIrkpISLgCGHTVCKMCLNKL----HRKaCP 51
Cdd:cd16499     7 LKCSVCNDRFKDVI---ITK-CGHVFCNECVQKRletrQRK-CP 45