BRcat domain found in an uncharacterized subfamily of RBR proteins; This subfamily contains uncharacterized members of the RBR family, including Arabidopsis thaliana mutator-like transposase, hypothetical protein F9K21.90, and hypothetical protein T16H5.30. The RBR family of RING-type E3 ligases are characterized by containing a RBR domain, which was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. It is composed of an extended RING domain (RING1) followed by an in-between RING (IBR) domain and the catalytic domain, which is structurally an IBR domain but is commonly designated RING2. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently, where the IBR and RING2 domains have been renamed as BRcat and Rcat domains, respectively. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. The BRcat domain adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 15231185 256 ERVYCPNPRCSSLMSVTKLSNstREDVTMRSCVKCGEPFCINCKLPWHSNLSCNDY 311
Cdd:cd22582   3 ERVYCPNPDCSALMSKDELLE--AEDDTPRECPKCRRLFCARCKVPWHAGLSCAEY 56

Ribonuclease H-like superfamily, including RNase H, HI, HII, HIII, and RNase-like domain IV of spliceosomal protein Prp8; Ribonuclease H (RNase H) enzymes are divided into two major families, Type 1 and Type 2, based on amino acid sequence similarities and biochemical properties. RNase H is an endonuclease that cleaves the RNA strand of an RNA/DNA hybrid in a sequence non-specific manner in the presence of divalent cations. It is widely present in various organisms, including bacteria, archaea, and eukaryotes. Most prokaryotic and eukaryotic genomes contain multiple RNase H genes. Despite the lack of amino acid sequence homology, type 1 and type 2 RNase H share a main-chain fold and steric configurations of the four acidic active-site residues and have the same catalytic mechanism and functions in cells. RNase H is involved in DNA replication, repair and transcription. An important RNase H function is to remove Okazaki fragments during DNA replication. RNase H inhibitors have been explored as anti-HIV drug targets since RNase H inactivation inhibits reverse transcription. This model also includes the Prp8 domain IV, which adopts the RNase fold but shows low sequence homology; domain IV is implicated in key spliceosomal interactions.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 15231185    44 LAGFGVAICDKDDNLLFQMKEQVHDSRvTVLEVEIMALKRGLTEAVGLGIDNISIYSDHYRIFELVMEKSASaEENFALL 123
Cdd:pfam13456  12 LAGAGVVIRDPNGNVLLAGQKKLGPGA-SVLEAEAQALIIGLQLAWKLGIRHLIVEGDSATVVQLINGRSPK-QSKLANL 89

                          90       100       110
                  ....*....|....*....|....*....|.
gi 15231185   124 MDNVQHIRQRLTSSFPVLVTRNQIKFVYELA 154
Cdd:pfam13456  90 LDEIRKLLKRFESVSFEHIPREQNRVADTLA 120

BRcat domain found in an uncharacterized subfamily of RBR proteins; This subfamily contains uncharacterized members of the RBR family, including Arabidopsis thaliana mutator-like transposase, hypothetical protein F9K21.90, and hypothetical protein T16H5.30. The RBR family of RING-type E3 ligases are characterized by containing a RBR domain, which was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. It is composed of an extended RING domain (RING1) followed by an in-between RING (IBR) domain and the catalytic domain, which is structurally an IBR domain but is commonly designated RING2. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently, where the IBR and RING2 domains have been renamed as BRcat and Rcat domains, respectively. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. The BRcat domain adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 15231185 256 ERVYCPNPRCSSLMSVTKLSNstREDVTMRSCVKCGEPFCINCKLPWHSNLSCNDY 311
Cdd:cd22582   3 ERVYCPNPDCSALMSKDELLE--AEDDTPRECPKCRRLFCARCKVPWHAGLSCAEY 56

Reverse transcriptase-like; This domain is found in plants and appears to be part of a retrotransposon.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 15231185    44 LAGFGVAICDKDDNLLFQMKEQVHDSRvTVLEVEIMALKRGLTEAVGLGIDNISIYSDHYRIFELVMEKSASaEENFALL 123
Cdd:pfam13456  12 LAGAGVVIRDPNGNVLLAGQKKLGPGA-SVLEAEAQALIIGLQLAWKLGIRHLIVEGDSATVVQLINGRSPK-QSKLANL 89

                          90       100       110
                  ....*....|....*....|....*....|.
gi 15231185   124 MDNVQHIRQRLTSSFPVLVTRNQIKFVYELA 154
Cdd:pfam13456  90 LDEIRKLLKRFESVSFEHIPREQNRVADTLA 120

IBR domain, a half RING-finger domain; The IBR (In Between Ring fingers) domain is often found to occur between pairs of ring fingers (pfam00097). This domain has also been called the C6HC domain and DRIL (for double RING finger linked) domain. Proteins that contain two Ring fingers and an IBR domain (these proteins are also termed RBR family proteins) are thought to exist in all eukaryotic organizms. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes. The ubiquitin ligase Parkin is an RBR family protein whose mutations are involved in forms of familial Parkinson's disease.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 15231185   256 ERVYCPNPRCSSLMSVTKLSNSTredvTMRSCVKCGEPFCINCKLPWHSNLSC 308
Cdd:pfam01485  17 NLKWCPTPDCGYIIELTDGCSNT----SHVTCSKCGHEFCFNCKEEWHEGLTC 65

RING finger, HC subclass, found in RING finger protein 14 (RNF14) and similar proteins; RNF14, also known as androgen receptor-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase that is highly expressed in the testis and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3). Its differential localization may play an important role in testicular development and spermatogenesis in humans. RNF14 functions as a transcriptional regulator of mitochondrial and immune function in muscle. It is a ligand-dependent androgen receptor (AR) co-activator and may also may participate in enhancing cell cycle progression and cell proliferation via induction of cyclin D1. Moreover, RNF14 is crucial for colon cancer cell survival. It acts as a new enhancer of the Wnt-dependent transcriptional outputs that acts at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex. RNF14 contains an N-terminal RWD domain and a C-terminal RBR domain. The RBR domain was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 15231185 172 TCSICSDDNFePELMFSVALCGHEFCVECVKRHIEVRLLAGGVP--RCLHYQCE 223
Cdd:cd16628   7 TCNICFLDKL-GSECMYFKDCGHVYCKECLKEYFEVQIRDGNVTslNCPEPKCA 59

In Between Ring fingers; the domains occurs between pairs og RING fingers

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|..
gi 15231185    323 IKLKALANQKMWRQC--ENCKNVIELSE--GCMHITC-RCGHQFCYKCGAKW 369
Cdd:smart00647   7 LLESYVESNPDLKWCpaPDCSAAIIVTEeeGCNRVTCpKCGFSFCFRCKVPW 58

BRcat domain found in an uncharacterized subfamily of RBR proteins; This subfamily contains uncharacterized members of the RBR family, including Arabidopsis thaliana mutator-like transposase, hypothetical protein F9K21.90, and hypothetical protein T16H5.30. The RBR family of RING-type E3 ligases are characterized by containing a RBR domain, which was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. It is composed of an extended RING domain (RING1) followed by an in-between RING (IBR) domain and the catalytic domain, which is structurally an IBR domain but is commonly designated RING2. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently, where the IBR and RING2 domains have been renamed as BRcat and Rcat domains, respectively. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. The BRcat domain adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 15231185 256 ERVYCPNPRCSSLMSVTKLSNstREDVTMRSCVKCGEPFCINCKLPWHSNLSCNDY 311
Cdd:cd22582   3 ERVYCPNPDCSALMSKDELLE--AEDDTPRECPKCRRLFCARCKVPWHAGLSCAEY 56

Reverse transcriptase-like; This domain is found in plants and appears to be part of a retrotransposon.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 15231185    44 LAGFGVAICDKDDNLLFQMKEQVHDSRvTVLEVEIMALKRGLTEAVGLGIDNISIYSDHYRIFELVMEKSASaEENFALL 123
Cdd:pfam13456  12 LAGAGVVIRDPNGNVLLAGQKKLGPGA-SVLEAEAQALIIGLQLAWKLGIRHLIVEGDSATVVQLINGRSPK-QSKLANL 89

                          90       100       110
                  ....*....|....*....|....*....|.
gi 15231185   124 MDNVQHIRQRLTSSFPVLVTRNQIKFVYELA 154
Cdd:pfam13456  90 LDEIRKLLKRFESVSFEHIPREQNRVADTLA 120

Rcat (required-for-catalysis) domain, part of the RBR (RING1-BRcat-Rcat) domain; The RBR family of RING-type E3 ligases are characterized by containing an RBR domain, which was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. It is composed of an extended RING domain (RING1) followed by an in-between RING (IBR) domain and the catalytic domain, which is structurally an IBR domain but is commonly designated RING2. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently, where the IBR and RING2 domains have been renamed as BRcat and Rcat domains, respectively. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. The Rcat domain contains the catalytic cysteine residue and ubiquitination activity. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes. This model corresponds to the Rcat domain that adopts the same fold as the BRcat domain.

                        10        20        30
                ....*....|....*....|....*....|....*..
gi 15231185 334 WRQCENCKNVIELSEGCMHITC-RCGHQFCYKCGAKW 369
Cdd:cd20336   2 TKKCPKCKVPIEKNGGCNHMTCsRCGTEFCWLCGKPW 38

Rcat domain found in E3 ubiquitin-protein ligase ARI7 and similar proteins; This subfamily contains probable RBR-type E3 ubiquitin-protein ligases (EC 2.3.2.31) including Arabidopsis thaliana ARI5, ARI6, ARI7, and ARI8, as well as Dictyostelium discoideum RbrA (also called Ariadne-like ubiquitin ligase). They may function as part of E3 complexes, which accept ubiquitin from E2 ubiquitin-conjugating enzymes and then transfer it to substrates. RbrA may be required for normal cell-type proportioning and cell sorting during multicellular development, and is also necessary for spore cell viability. Members of this subfamily contain an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of ARI7-like proteins that are essential for RBR E3 ligase activity and adopt the same fold as the BRcat domain.

                        10        20        30
                ....*....|....*....|....*....|....*..
gi 15231185 335 RQCENCKNVIELSEGCMHITCR--CGHQFCYKCGAKW 369
Cdd:cd22583   3 KPCPKCKRPIEKNQGCMHMTCSppCKHEFCWLCLGPW 39

BRcat domain found in the RNF144 protein subfamily; The RNF144 subfamily includes RNF144A and RNF144B, which are transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligases. RNF144A, also called UbcM4-interacting protein 4 (UIP4), or ubiquitin-conjugating enzyme 7-interacting protein 4, targets DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and thus promotes DNA damage-induced cell apoptosis. It is transcriptionally repressed by metastasis-associated protein 1 (MTA1) and inhibits MTA1-driven cancer cell migration and invasion. RNF144B, also called PIR2, IBR domain-containing protein 2 (IBRDC2), or p53-inducible RING finger protein (p53RFP), induces p53-dependent but caspase-independent apoptosis. It interacts with E2 ubiquitin-conjugating enzymes UbcH7 and UbcH8, but not with UbcH5. It is involved in ubiquitination and degradation of p21, a p53 downstream protein promoting growth arrest and antagonizing apoptosis, suggesting a role in switching a cell from p53-mediated growth arrest to apoptosis. Moreover, RNF144B regulates the levels of Bax, a pro-apoptotic protein from the Bcl-2 family, and protects cells from unprompted Bax activation and cell death. It also regulates epithelial homeostasis by mediating degradation of p21WAF1 and p63. Both RNF144A and RNF144B contain an RBR domain followed by a potential single-TM domain. The RBR domain was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of the RNF144 protein subfamily that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 15231185 257 RVYCPNPRCSSLMSVTKLSNSTREDVTMRSCVKCGEPFCINCKLPWHSNLSCNDYKS 313
Cdd:cd20349   8 RTWCPRAGCETVCHVCPPSGSAPVTAVPVQCPKCGLTFCSICKAAWHAGQSCDENMK 64

Rcat domain found in cullin-9 (CUL-9) and similar proteins; CUL-9, also called UbcH7-associated protein 1 (H7-AP1), p53-associated parkin-like cytoplasmic protein, or PARC, is a cytoplasmic RBR-type E3 ubiquitin-protein ligase that function as a tumor suppressor and promotes p53-dependent apoptosis. It mediates the ubiquitination and degradation of cytosolic cytochrome c to promote survival in neurons and cancer cells. It is also a critical downstream effector of the 3M complex in the maintenance of microtubules and genome integrity. Moreover, CUL-9, together with CUL-7, forms homodimers and heterodimers, as well as some atypical cullin RING ligase complexes, which may exhibit ubiquitin ligase activity. CUL-9 contains a CPH domain (conserved in Cul7, PARC, and HERC2 proteins), a DOC (DOC1/APC10) domain, cullin homology domains linked with E3 ligase function, and a C-terminal RBR domain previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of CUL-9 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                        10        20        30
                ....*....|....*....|....*....|....*.
gi 15231185 335 RQCENCKNVIELSEGCMHITC-RCGHQFCYKCGAKW 369
Cdd:cd20359   8 KRCPSCQAQIEKNEGCLHMTCaKCNHGFCWRCLKPW 43

Rcat domain found in RING finger protein 216 (RNF216); RNF216, also called Triad domain-containing protein 3 (Triad3A), ubiquitin-conjugating enzyme 7-interacting protein 1, or zinc finger protein inhibiting NF-kappa-B (ZIN), is an RBR-type E3 ubiquitin-protein ligase that interacts with several components of the Toll-like receptor (TLR) signaling and promotes their proteolytic degradation. It negatively regulates the RIG-I RNA sensing pathway through Lys48-linked, ubiquitin-mediated degradation of the tumor necrosis factor receptor-associated factor 3 (TRAF3) adapter following RNA virus infection. It also controls ubiquitination and proteasomal degradation of receptor-interacting protein 1 (RIP1), a serine/threonine protein kinase that is critically involved in tumor necrosis factor receptor-1 (TNF-R1)-induced NF-kappa B activation, following disruption of Hsp90 binding. Moreover, RNF216 is involved in inflammatory diseases by strongly inhibiting autophagy in macrophages. It interacts with and ubiquitinates BECN1, a key regulator in autophagy, thereby contributing to BECN1 degradation. It regulates synaptic strength by ubiquitination of Arc, resulting in its rapid proteasomal degradation. It is also a key negative regulator of sustained 2DL4/KIR2DL4 (killer cell Ig-like receptor with two Ig-like domains and a long cytoplasmic domain 4)-mediated NF-kappaB signaling from internalized 2DL4, which functions by promoting ubiquitylation and degradation of endocytosed receptor from early endosomes. Furthermore, RNF216 interacts with human immunodeficiency virus type 1 (HIV-1) virion infectivity factor (Vif) protein, which is essential for the productive infection of primary human CD4 T lymphocytes and macrophages. Mutations in RNF216 may result in Gordon Holmes syndrome, a condition defined by hypogonadotropic hypogonadism and cerebellar ataxia, as well as in autosomal recessive Huntington-like disorder. RNF216 contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. The family corresponds to the Rcat domain of RNF216 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 15231185 330 NQKMWRQCENCKNVIELSEGCMHITCRCGHQFCYKCGAKWITGRVFCTHSRPP 382
Cdd:cd20353   5 TEALIRTCPKCKTKFIKSEGCNKMTCRCGAKMCYICRKPIKGYDHFCQHPRDP 57

BRcat domain found in RING finger protein 14 (RNF14); RNF14, also called androgen receptor (AR)-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase that is highly expressed in the testis and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3). Its differential localization may play an important role in testicular development and spermatogenesis in humans. RNF14 functions as a transcriptional regulator of mitochondrial and immune function in muscles. It is a ligand-dependent AR co-activator that enhances AR-dependent transcriptional activation. It may also participate in enhancing cell cycle progression and cell proliferation via induction of cyclin D1. Moreover, RNF14 is crucial for colon cancer cell survival. It acts as a new enhancer of the Wnt-dependent transcriptional outputs that acts at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex. RNF14 contains an N-terminal RWD domain, and a C-terminal RBR domain. The RBR domain was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of RNF14 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 15231185 258 VYCPNPRCSSLMSVTklsnstrEDVTMRSCVKCGEPFCINCKLPWHSNLSC 308
Cdd:cd20341   8 VYCPRPSCQTPVILE-------PDENLGICPSCNYAFCTLCRETYHGVSPC 51

Rcat domain found in human homolog of Drosophila Ariadne (HHARI) and similar proteins; This subfamily includes Drosophila melanogaster protein ariadne-1 (ARI-1), and its eukaryotic homologs, such as HHARI. ARI-1 is a widely expressed Drosophila RING-finger protein that localizes mainly in the cytoplasm, and is required for neural development. It interacts with the ubiquitin-conjugating enzyme, UbcD10. HHARI is also called H7-AP2, monocyte protein 6 (MOP-6), protein ariadne-1 homolog, Ariadne RBR E3 ubiquitin protein ligase 1 (ARIH1), ariadne-1 (ARI-1), UbcH7-binding protein, UbcM4-interacting protein, or ubiquitin-conjugating enzyme E2-binding protein. It is an RBR-type E3 ubiquitin-protein ligase highly expressed in nuclei, where it is co-localized with nuclear bodies including Cajal, PML, and Lewy bodies. It interacts with the E2 conjugating enzymes UbcH7, UbcH8, UbcM4 and UbcD10 in human, mouse and fly, and modulates the ubiquitylation of substrate proteins including single-minded 2 (SIM2) and translation initiation factor 4E homologous protein (4EHP). It functions as a potent mediator of DNA damage-induced translation arrest, which protects stem and cancer cells against genotoxic stress by initiating a 4EHP-mediated mRNA translation arrest. HHARI contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of HHARI and similar proteins that are essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                        10        20        30
                ....*....|....*....|....*....|....*...
gi 15231185 335 RQCENCKNVIELSEGCMHITCR---CGHQFCYKCGAKW 369
Cdd:cd20356   7 KECPKCHVTIEKNGGCNHMVCRnqnCKYEFCWVCLGPW 44

RING finger, HC subclass, found in RING finger protein 14 (RNF14) and similar proteins; RNF14, also known as androgen receptor-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase that is highly expressed in the testis and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3). Its differential localization may play an important role in testicular development and spermatogenesis in humans. RNF14 functions as a transcriptional regulator of mitochondrial and immune function in muscle. It is a ligand-dependent androgen receptor (AR) co-activator and may also may participate in enhancing cell cycle progression and cell proliferation via induction of cyclin D1. Moreover, RNF14 is crucial for colon cancer cell survival. It acts as a new enhancer of the Wnt-dependent transcriptional outputs that acts at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex. RNF14 contains an N-terminal RWD domain and a C-terminal RBR domain. The RBR domain was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 15231185 172 TCSICSDDNFePELMFSVALCGHEFCVECVKRHIEVRLLAGGVP--RCLHYQCE 223
Cdd:cd16628   7 TCNICFLDKL-GSECMYFKDCGHVYCKECLKEYFEVQIRDGNVTslNCPEPKCA 59

Rcat domain found in ankyrin repeat and IBR domain-containing protein 1 (ANKIB1) and similar proteins; ANKIB1 is an RBR-type E3 ubiquitin-protein ligase that may function as part of an E3 complex, which accepts ubiquitin from specific E2 ubiquitin-conjugating enzymes and then transfers it to substrates. It contains N-terminal ankyrin repeats, and an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of ANKIB1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                        10        20        30
                ....*....|....*....|....*....|....
gi 15231185 337 CENCKNVIELSEGCMHITCR-CGHQFCYKCGAKW 369
Cdd:cd20361  12 CPNCKSPIQKNEGCNHMKCSkCKYDFCWVCLEEW 45

Rcat domain of ATP-dependent RNA helicase DEAH12 and similar proteins; This group includes Arabidopsis thaliana ATP-dependent RNA helicases DEAH11 and DEAH12, which may be bifunctional proteins that function as DEAD-box RNA helicases (EC 3.6.4.13) and RBR-type E3 ubiquitin-protein ligases (EC 2.3.2.31). As RNA helicases, they may utilize the energy from ATP hydrolysis to unwind RNA (or DNA). DEAD-box RNA helicases participate in every aspect of RNA metabolism. As E3 ubiquitin-protein ligase, they may function as part of E3 complexes, which accept ubiquitin from specific E2 ubiquitin-conjugating enzymes and then transfer it to substrates. Other members of this group may not have an RNA helicase domain. All members contain an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

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                ....*....|....*....|....*....|..
gi 15231185 335 RQCENCKNVIELSEGCMHITC-RCGHQFCYKC 365
Cdd:cd22585   3 KRCPKCKSLIEKIDGCNHVTCtRCGTHICWVC 34

RING finger, HC subclass, found in two RING fingers and DRIL [double RING finger linked] 1 (TRIAD1); TRIAD1, also known as ariadne-2 (ARI-2), protein ariadne-2 homolog, Ariadne RBR E3 ubiquitin protein ligase 2 (ARIH2), or UbcM4-interacting protein 48, is an RBR-type E3 ubiquitin-protein ligase that catalyzes the formation of polyubiquitin chains linked via lysine-48, as well as lysine-63 residues. Its auto-ubiquitylation can be catalyzed by the E2 conjugating enzyme UBCH7. TRIAD1 has been implicated in hematopoiesis, specifically in myelopoiesis, as well as in embryogenesis. It functions as a regulator of endosomal transport and is required for the proper function of multivesicular bodies. It also acts as a novel ubiquitination target for proteasome-dependent degradation by murine double minute 2 (MDM2). As a proapoptotic protein, TRIAD1 promotes p53 activation, and inhibits MDM2-mediated p53 ubiquitination and degradation. Furthermore, TRIAD1 can inhibit the ubiquitination and proteasomal degradation of growth factor independence 1 (Gfi1), a transcriptional repressor essential for the function and development of many different hematopoietic lineages. TRIAD1 contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

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                ....*....|....*....|....*....|....*....|....*....|....*
gi 15231185 172 TCSICSDDnFEPELMFSVAlCGHEFCVECVKRHIEVRLLAGGVP--RCLHYQCES 224
Cdd:cd16773   2 TCGVCCED-VPKDELFSLA-CGHYFCNDCWKQYLTVKIKDGVSTgiECMAPDCKV 54

BRcat domain found in human homolog of Drosophila Ariadne (HHARI) and similar proteins; This subfamily includes Drosophila melanogaster protein ariadne-1 (ARI-1), and its eukaryotic homologs, such as HHARI. ARI-1 is a widely expressed Drosophila RING-finger protein that localizes mainly in the cytoplasm, and is required for neural development. It interacts with the ubiquitin-conjugating enzyme, UbcD10. HHARI is also called H7-AP2, monocyte protein 6 (MOP-6), protein ariadne-1 homolog, Ariadne RBR E3 ubiquitin protein ligase 1 (ARIH1), ariadne-1 (ARI-1), UbcH7-binding protein, UbcM4-interacting protein, or ubiquitin-conjugating enzyme E2-binding protein 1. It is an RBR-type E3 ubiquitin-protein ligase highly expressed in nuclei, where it is co-localized with nuclear bodies including Cajal, PML, and Lewy bodies. It interacts with the E2 conjugating enzymes UbcH7, UbcH8, UbcM4, and UbcD10 in human, mouse and fly, and modulates the ubiquitylation of substrate proteins including single-minded 2 (SIM2) and translation initiation factor 4E homologous protein (4EHP). It functions as a potent mediator of DNA damage-induced translation arrest, which protects stem and cancer cells against genotoxic stress by initiating a 4EHP-mediated mRNA translation arrest. HHARI contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of HHARI and similar proteins that adopt the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                        10        20        30
                ....*....|....*....|....*....|..
gi 15231185 339 NCKNVIELSEG-CMHITCRCGHQFCYKCGAKW 369
Cdd:cd20343  30 DCGHAVKVQYPdARPVTCKCGHTFCFACGENW 61

RNAse HI family that includes archaeal, some bacterial as well as plant RNase HI; Ribonuclease H (RNase H) is classified into two evolutionarily unrelated families, type 1 (prokaryotic RNase HI, eukaryotic RNase H1 and viral RNase H) and type 2 (prokaryotic RNase HII and HIII, and eukaryotic RNase H2). RNase H is an endonuclease that cleaves the RNA strand of an RNA/DNA hybrid in a sequence non-specific manner. RNase H is involved in DNA replication, repair and transcription. RNase H is widely present in various organisms, including bacteria, archaea and eukaryotes and most prokaryotic and eukaryotic genomes contain multiple RNase H genes. Despite the lack of amino acid sequence homology, type 1 and type 2 RNase H share a main-chain fold and steric configurations of the four acidic active-site (DEDD) residues and have the same catalytic mechanism and functions in cells. One of the important functions of RNase H is to remove Okazaki fragments during DNA replication. Most archaeal genomes contain only type 2 RNase H (RNase HII); however, a few contain RNase HI as well. Although archaeal RNase HI sequences conserve the DEDD active-site motif, they lack other common features important for catalytic function, such as the basic protrusion region. Archaeal RNase HI homologs are more closely related to retroviral RNase HI than bacterial and eukaryotic type I RNase H in enzymatic properties.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 15231185  45 AGFGVAICDkDDNLLFQMKEQVHdSRVTVLEVEIMALKRGLTEAVGLGIDNISIYSDhyriFELV---MEKSASA-EENF 120
Cdd:cd09279  16 AGAGVVIYS-PGGEVLELSERLG-FPATNNEAEYEALIAGLELALELGAEKLEIYGD----SQLVvnqLNGEYKVkNERL 89

                        90       100       110
                ....*....|....*....|....*....|....*...
gi 15231185 121 ALLMDNVQHIRQRLTSSFPVLVTRNQIKFVYELAMETI 158
Cdd:cd09279  90 KPLLEKVLELLAKFELVELKWIPREQNKEADALANQAL 127

In Between Ring fingers; the domains occurs between pairs og RING fingers

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                   ....*....|....*....|....*....|....*....|....*....|..
gi 15231185    323 IKLKALANQKMWRQC--ENCKNVIELSE--GCMHITC-RCGHQFCYKCGAKW 369
Cdd:smart00647   7 LLESYVESNPDLKWCpaPDCSAAIIVTEeeGCNRVTCpKCGFSFCFRCKVPW 58

BRcat domain found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also called RING finger protein 31 (RNF31) or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains three Npl4 zinc fingers, a central ubiquitin-associated (UBA) domain responsible for interaction with the N-terminal ubiquitin-like domain (UBL) of HOIL-1L, an RBR domain, and a C-terminal linear chain determining domain (LDD). The RBR domain was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of HOIP and similar proteins that adopt the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                        10        20
                ....*....|....*....|....*....
gi 15231185 287 CVKCGEPFCINCKLPW---HSNLSCNDYK 312
Cdd:cd20337  43 CPQCGKVTCFKCKKPWedqHEGISCEQFQ 71