RWD domain of RING finger protein 14 (RNF14) and related proteins; RNF14, also called androgen receptor (AR)-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase (EC 2.3.2.31) 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 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 Wnt-dependent transcriptional outputs that act at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217357919   9 QEDELLALASIYDGDEFRKAESvqgGETRIYLDLPQNFKIFVSGNSNECLQNSG-FEYTICFLPPLVLNFELPPDYPSSS 87
Cdd:cd23820     1 QEDELEALEAIYPDDLVVDSDS---SSGRGSLEIPVELEPPLSVVLSSDGSDEGeRTLKVSHLPPITLRFSLPPGYPSTS 77

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*...
gi 2217357919  88 PPSFTLSGKWLSPTQLSALCKHLDNLWEEHRGSVVLFAWMQFLKEETL 135
Cdd:cd23820    78 PPEFTLECSWLSPEQLSALCERLDELWEENGGDVVLFSWIDFLQDEAL 125

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 2217357919 300 LDLMADVVYCPRPCCQLPVMQEPGCTMGICSSCNFAFCTLCRLTYHGVSPCKVTAEK 356
Cdd:cd20341     1 LDSMPDVVYCPRPSCQTPVILEPDENLGICPSCNYAFCTLCRETYHGVSPCKIKEEK 57

RWD domain of RING finger protein 14 (RNF14) and related proteins; RNF14, also called androgen receptor (AR)-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase (EC 2.3.2.31) 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 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 Wnt-dependent transcriptional outputs that act at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217357919   9 QEDELLALASIYDGDEFRKAESvqgGETRIYLDLPQNFKIFVSGNSNECLQNSG-FEYTICFLPPLVLNFELPPDYPSSS 87
Cdd:cd23820     1 QEDELEALEAIYPDDLVVDSDS---SSGRGSLEIPVELEPPLSVVLSSDGSDEGeRTLKVSHLPPITLRFSLPPGYPSTS 77

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*...
gi 2217357919  88 PPSFTLSGKWLSPTQLSALCKHLDNLWEEHRGSVVLFAWMQFLKEETL 135
Cdd:cd23820    78 PPEFTLECSWLSPEQLSALCERLDELWEENGGDVVLFSWIDFLQDEAL 125

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 2217357919 300 LDLMADVVYCPRPCCQLPVMQEPGCTMGICSSCNFAFCTLCRLTYHGVSPCKVTAEK 356
Cdd:cd20341     1 LDSMPDVVYCPRPSCQTPVILEPDENLGICPSCNYAFCTLCRETYHGVSPCKIKEEK 57

domain in RING finger and WD repeat containing proteins and DEXDc-like helicases subfamily related to the UBCc domain;

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217357919   12 ELLALASIYDGDEFRKAESVQGGETRIYLDLPQNfkifvsgnsneclqnsgfeYTICFLPPLVLNFELPPDYPSSSPPSF 91
Cdd:smart00591   1 ELEALESIYPEDFEVIDEDARIPEITIKLSPSSD-------------------EGEDQYVSLTLQVKLPENYPDEAPPIS 61

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|..
gi 2217357919   92 TLSGKWLSPTQLSALCKHLDNLWEEHRGSVVLFAWMQFLKEE 133
Cdd:smart00591  62 LLNSEGLSDEQLAELLKKLEEIAEENLGEVMIFELVEKLQEF 103

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217357919 290 RYDRLLLQSSLDLMADVVYCPRPCCQLPVMQEPGCT---MGICSSCNFAFCTLCRLTYHGVSPC 350
Cdd:pfam01485   2 KYEKLLLKSYVESDPNLKWCPTPDCGYIIELTDGCSntsHVTCSKCGHEFCFNCKEEWHEGLTC 65

RWD domain of RING finger protein 14 (RNF14) and related proteins; RNF14, also called androgen receptor (AR)-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase (EC 2.3.2.31) 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 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 Wnt-dependent transcriptional outputs that act at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217357919   9 QEDELLALASIYDGDEFRKAESvqgGETRIYLDLPQNFKIFVSGNSNECLQNSG-FEYTICFLPPLVLNFELPPDYPSSS 87
Cdd:cd23820     1 QEDELEALEAIYPDDLVVDSDS---SSGRGSLEIPVELEPPLSVVLSSDGSDEGeRTLKVSHLPPITLRFSLPPGYPSTS 77

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*...
gi 2217357919  88 PPSFTLSGKWLSPTQLSALCKHLDNLWEEHRGSVVLFAWMQFLKEETL 135
Cdd:cd23820    78 PPEFTLECSWLSPEQLSALCERLDELWEENGGDVVLFSWIDFLQDEAL 125

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 2217357919 300 LDLMADVVYCPRPCCQLPVMQEPGCTMGICSSCNFAFCTLCRLTYHGVSPCKVTAEK 356
Cdd:cd20341     1 LDSMPDVVYCPRPSCQTPVILEPDENLGICPSCNYAFCTLCRETYHGVSPCKIKEEK 57

RWD domain; This domain was identified in WD40 repeat proteins and Ring finger domain proteins. The function of this domain is unknown. GCN2 is the alpha-subunit of the only translation initiation factor (eIF2 alpha) kinase that appears in all eukaryotes. Its function requires an interaction with GCN1 via the domain at its N-terminus, which is termed the RWD domain after three major RWD-containing proteins: RING finger-containing proteins, WD-repeat-containing proteins, and yeast DEAD (DEXD)-like helicases. The structure forms an alpha + beta sandwich fold consisting of two layers: a four-stranded antiparallel beta-sheet, and three side-by-side alpha-helices.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217357919   7 EAQEDELLALASIYDGDEFRKAESV-QGGETRIYLDLPQNfkifvsgnsneclqnsgfEYTICFLPPLVLNFEL------ 79
Cdd:pfam05773   1 EEQEEELEALESIYPDEFEVISDSPyESLEIEIKLSLDSD------------------ESDSSHLPPLVLKFTLpedypd 62

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 2217357919  80 ---PpdypsssppsFTLSGKW-LSPTQLSALCKHLDNLWEEHRGSVVLFAWMQFLKEE 133
Cdd:pfam05773  63 eppK----------ISLSSPWnLSDEQVLSLLEELEELAEENLGEVMIFELIEWLQEN 110

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        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2217357919 396 WLEKNSKSCPCCGTPIEKLDGCNKMTCTGCMQYFCWICMGSLSRANP 442
Cdd:cd20361     4 WLVTNSKPCPNCKSPIQKNEGCNHMKCSKCKYDFCWVCLEEWKKHSS 50

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

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217357919  289 ARYDRLLLQSSLDLMADVVYCPRP-CCQLPVMQEP-GCTMGICSSCNFAFCTLCRLTYHGVSPC 350
Cdd:smart00647   1 EKYERLLLESYVESNPDLKWCPAPdCSAAIIVTEEeGCNRVTCPKCGFSFCFRCKVPWHSPVSC 64

Rcat domain found in two RING fingers and DRIL [double RING finger linked] 1 (TRIAD1); TRIAD1, also called 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 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 TRIAD1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 2217357919 400 NSKSCPCCGTPIEKLDGCNKMTCTGCMQYFCWICMGS 436
Cdd:cd20360     2 HTKDCPKCHVCIEKNGGCNHMQCSKCKHEFCWMCLGD 38

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 2217357919 218 FLCSICFCEKLGSEcMYFLECRHVYCKACLKDYFEIQIRDGQVQCLNCPEPKCPS 272
Cdd:cd16773     1 VTCGVCCEDVPKDE-LFSLACGHYFCNDCWKQYLTVKIKDGVSTGIECMAPDCKV 54

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 2217357919 400 NSKSCPCCGTPIEKLDGCNKMTCTG-CMQYFCWICMG 435
Cdd:cd22583     1 NTKPCPKCKRPIEKNQGCMHMTCSPpCKHEFCWLCLG 37

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2217357919 290 RYDRLLLQSSLDLMADVVYCPRPCCQLPVMQEPGCT---MGICSSCNFAFCTLCRLTYHGVSPC 350
Cdd:pfam01485   2 KYEKLLLKSYVESDPNLKWCPTPDCGYIIELTDGCSntsHVTCSKCGHEFCFNCKEEWHEGLTC 65

Rcat domain found in RING finger protein 144B (RNF144B); RNF144B, also called PIR2, IBR domain-containing protein 2 (IBRDC2), or p53-inducible RING finger protein (p53RFP), is a transmembrane (TM) domain-containing RBR E3 ubiquitin-protein ligase that 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. RNF144B contains 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 Rcat domain of RNF144B that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2217357919 402 KSCPCCGTPIEKLDGCNKMTCTGCMQYFCWICMGSLSRANPYKHFNDpgSPCFNRL 457
Cdd:cd20369     7 KQCPVCRVYIERNEGCAQMMCKNCKHTFCWYCLQNLDNDIFLRHYDK--GPCRNKL 60

Rcat domain found in the RING finger protein 19 (RNF19) subfamily; This subfamily includes RING finger protein RNF19A and RNF19B, which are transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligases. RNF19A, also called double ring-finger protein (Dorfin) or p38, localizes to the ubiquitylated inclusions in Parkinson's disease (PD), dementia with Lewy bodies (LBs), multiple system atrophy, and amyotrophic lateral sclerosis (ALS). It interacts with Psmc3, a protein component of the 19S regulatory cap of the 26S proteasome, and further participates in the ubiquitin-proteasome system in acrosome biogenesis, spermatid head shaping, and development of the head-tail coupling apparatus and tail. It modulates the ubiquitination and degradation of calcium-sensing receptor (CaR), which may contribute to a general mechanism for CaR quality control during biosynthesis. Moreover, RNF19A can also ubiquitylate mutant superoxide dismutase 1 (SOD1), the causative gene of familial ALS. It may associate with the endoplasmic reticulum-associated degradation (ERAD) pathway, which is related to the pathogenesis of neurodegenerative disorders, such as PD or Alzheimer's disease. It is also involved in the pathogenic process of PD and LB formation by ubiquitylation of synphilin-1. RNF19B, also called IBR domain-containing protein 3, or natural killer (NK) lytic-associated molecule (NKLAM), plays a role in controlling tumor dissemination and metastasis. It is involved in the cytolytic function of NK cells and cytotoxic T lymphocytes (CTLs). It interacts with ubiquitin conjugates UbcH7 and UbcH8, and ubiquitinates uridine kinase like-1 protein, targeting it for degradation. RNF19B is a novel component of macrophage phagosomes and plays a role in macrophage anti-bacterial activity. It functions as a novel modulator of macrophage inducible nitric oxide synthase (iNOS) expression. Both RNF19A and RNF19B contain an RBR domain followed by three TMs. 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 Rcat domain of the RNF19 subfamily that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 2217357919 402 KSCPCCGTPIEKLD--GCNKMTCTGCMQYFCWICMGSLS 438
Cdd:cd20355     5 KPCPRCGALIIKMDdgSCNHMTCAVCGAEFCWLCMKEIS 43

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2217357919 220 CSICFCEKLGSECMYFLECRHVYCKACLKDYFEIQIRDGQVQ-CLNCPEP 268
Cdd:cd23131     6 CSICTQEPIEVGEVVFTECGHSFCEDCLLEYIEFQNKKKLDLkCPNCREP 55

Rcat domain found in RING finger protein 144A (RNF144A); RNF144A, also called UbcM4-interacting protein 4 (UIP4), or ubiquitin-conjugating enzyme 7-interacting protein 4, is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that 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. RNF144A contains 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 Rcat domain of RNF144A that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2217357919 402 KSCPCCGTPIEKLDGCNKMTCTGCMQYFCWICMGSLSRANPYKHFNDpgSPCFNRL 457
Cdd:cd20368     7 KRCPKCKVYIERDEGCAQMMCKNCKHAFCWYCLESLDDDFLLIHYDK--GPCRNKL 60

BRcat domain found in early mitotic inhibitor (EMI) subfamily of F-box proteins; The EMI subfamily includes FBXO5 (EMI1) and FBXO43 (EMI2), which are anaphase-promoting-complex/cyclosome (APC/C) inhibitors that bind APC/C-CCD20 (Cell division cycle protein 20) and/or APC/C-CDH1 (CDC20 homolog 1) complexes. FBXO5, also called FBX5, or early mitotic inhibitor 1 (EMI1), acts as a regulator that inhibits the anaphase-promoting complex/cyclosome (APC/C), which controls cell cycle progression through the sequential degradation of various substrates from S phase to early mitosis. During the mitotic cell cycle, it plays a role as both substrate and inhibitor of the APC-FZR1 complex. During G1 phase, it plays a role as substrate of the APC-FZR1 complex E3 ligase. FBXO43, also called FBX43, or endogenous meiotic inhibitor 2 (EMI2), plays a key role during the meiotic cell cycle. It is required to establish and maintain the arrest of oocytes at the second meiotic metaphase until fertilization. It probably acts by inhibiting the APC/C ubiquitin ligase. It may recognize and bind to some phosphorylated proteins and promote their ubiquitination and degradation. Both FBXO5 and FBXO43 contain an F-box domain, and the first half of the 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 the EMI subfamily that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2217357919 309 CPRpcCQLPVMQEPGCTMGICSS--CNFAFCTLCRLTYHGVSPCKV 352
Cdd:cd20348     7 CPR--CSSPAKVDPVEQRATCTRetCGFDFCTKCLCEFHGSKPCPT 50

RWD domain of eIF-2-alpha kinase GCN2 and related proteins; GCN2 (EC 2.7.11.1), also called eukaryotic translation initiation factor 2-alpha kinase 4 (EIF2AK4), acts as a metabolic-stress sensing protein kinase that phosphorylates the alpha subunit of eukaryotic translation initiation factor 2 (EIF2S1/eIF-2-alpha) in response to low amino acid availability. It also plays a role in modulating the adaptive immune response to yellow fever virus infection and promotes dendritic cells to initiate autophagy and antigene presentation to both CD4(+) and CD8(+) T-cells under amino acid starvation.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2217357919   6 REAQEDELLALASIYdGDEFRKAESVQGGETriyldlPQNFKIFVSGNSNECLQNSG-----FEYTICFlpPLVL-NFEL 79
Cdd:cd23823     1 EEEQEEELEALQSIY-GDDFEDLSSKKAVWS------PPEFRIRLRPQEGESEENHVsvdlhVKFPPTY--PDVPpEIEL 71

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2217357919  80 ppdypsssppsftLSGKWLSPTQLSALCKHLDNLWEEHRGSVVLFAWMQFLKE 132
Cdd:cd23823    72 -------------ENVKGLSDEQLEELLKELEELAKELLGEEMIFELAEAVQE 111

Rcat domain found in an uncharacterized subfamily of RBR proteins; This subfamily contains uncharacterized members of the RBR family, including Arabidopsis thaliana mutator-like transposase and hypothetical protein At2g19610/F3P11.21. 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. 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 is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                          10        20        30
                  ....*....|....*....|....*....|..
gi 2217357919 402 KSCPCCGTPIEKLDGCNKMTCtGCMQYFCWIC 433
Cdd:cd22584     3 RRCPQCGHMVELSEGCNHMTC-RCGYEFCYLC 33

RING finger, HC subclass, found in Saccharomyces cerevisiae histone E3 ligase 2 (HEL2) and similar proteins; HEL2 is an E3 ubiquitin-protein ligase that interacts with the E2 ubiquitin-conjugating enzyme UBC4 and histones H3 and H4. It plays an important role in regulating histone protein levels and also likely to contribute to the maintenance of genomic stability in the budding yeast. HEL2 can be phosphorylated by the DNA damage checkpoint kinase and histone protein regulator Rad53. This subfamily also includes Schizosaccharomyces pombe histone E3 ligase 1 (HEL1), also known as DNA-break-localizing protein 4 (dbl4), and Dictyostelium discoideum Ariadne-like ubiquitin ligase (RbrA). RbrA may act as an E3 ubiquitin-protein ligase that appears to 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 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 2217357919 218 FLCSICfCEKLGSEcMYFLECRHVYCKACLKDYFEIQIRDGQVQCL-NCPEPKC 270
Cdd:cd16625     1 FECPIC-CDDGELE-TFSLECGHEFCVDCYSQYLTSKIKEEGEGCRiTCPGEKC 52

BRcat (benign-catalytic) 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 as 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 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. The model corresponds to the BRcat domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2217357919 304 ADVVYCPRPCCQ--LPVMQEPGCTMGICSSCNFAFCTLCRLTYHGVSPCK 351
Cdd:cd20335     2 PNLRWCPTPDCGgvIRVEEPGDGPRVTCPSCGTSFCFKCKEEWHEGLTCE 51

BRcat domain found in F-box only protein 43 (FBXO43); FBXO43, also called FBX43 or endogenous meiotic inhibitor 2 (EMI2), plays a key role during the meiotic cell cycle. It is required to establish and maintain the arrest of oocytes at the second meiotic metaphase until fertilization. It probably acts by inhibiting the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. It may recognize and bind to some phosphorylated proteins and promotes their ubiquitination and degradation. FBXO43 contains an F-box domain, and the first half of the 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 (benign-catalytic) domain that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2217357919 309 CPRpcCQLPVMQEPGCTMGICSS--CNFAFCTLCRLTYHGVSPC 350
Cdd:cd20365     7 CPR--CQSPAKYQPVKKRGLCSReaCGFDFCVLCLCAFHGSKEC 48

Modified RING finger, HC subclass (C4C4-type), found in RING finger protein 144A (RNF144A); RNF144A, also known as UbcM4-interacting protein 4 (UIP4) or ubiquitin-conjugating enzyme 7-interacting protein 4, is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that 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. RNF144A contains 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 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 C4C4-type RING finger whose overall folding is similar to that of the C3HC4-type RING-HC finger. It is responsible for the interaction of E2-conjugating enzymes UbcH7 and UbcH8.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 2217357919 220 CSICFCEKLGSECMYFLECRHVYCKACLKDYFEIQIRDGQVQCLNCPEPKCP 271
Cdd:cd16777     3 CKLCLGEYPVEQMTTIAQCQCIFCTLCLKQYVELLIKEGLETAISCPDAACP 54

Rcat domain found in RING finger protein 19B (RNF19B); RNF19B, also called IBR domain-containing protein 3, or natural killer (NK) lytic-associated molecule (NKLAM), is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that plays a role in controlling tumor dissemination and metastasis. It is involved in the cytolytic function of NK cells and cytotoxic T lymphocytes (CTLs). It interacts with ubiquitin conjugates UbcH7 and UbcH8, and ubiquitinates uridine kinase like-1 protein, targeting it for degradation. Moreover, RNF19B is a novel component of macrophage phagosomes and plays a role in macrophage anti-bacterial activity. It functions as a novel modulator of macrophage inducible nitric oxide synthase (iNOS) expression. RNF19B contains an RBR domain followed by three TMs. 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 Rcat domain of RNF19B that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 2217357919 402 KSCPCCGTPIEKLD--GCNKMTCTGCMQYFCWICMGSLS 438
Cdd:cd20371     5 KPCPRCSAYIIKMNdgSCNHMTCAVCGCEFCWLCMKEIS 43

BRcat domain found in parkin and similar proteins; Parkin, also called Parkinson juvenile disease protein 2, is an RBR-type E3 ubiquitin-protein ligase that is associated with recessive early onset Parkinson's disease (PD), and exerts a protective effect against dopamine-induced alpha-synuclein-dependent cell toxicity. Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism. Parkin functions within a multiprotein E3 ubiquitin ligase complex, catalyzing the covalent attachment of ubiquitin moieties onto substrate proteins, such as BCL2, SYT11, CCNE1, GPR37, RHOT1/MIRO1, MFN1, MFN2, STUB1, SNCAIP, SEPT5, TOMM20, USP30, ZNF746 and AIMP2. It mediates monoubiquitination as well as Lys6-, Lys11-, Lys48- and Lys63-linked polyubiquitination of substrates depending on the context. Parkin may enhance cell viability and protects dopaminergic neurons from oxidative stress-mediated death by regulating mitochondrial function. It also limits the production of reactive oxygen species (ROS), and regulates cyclin-E during neuronal apoptosis. Moreover, parkin displays a ubiquitin ligase-independent function in transcriptional repression of p53. Parkin contains an N-terminal ubiquitin-like domain and a C-terminal 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 parkin that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2217357919 286 ELFARYDRLLLQSSLDLMADVVyCPRPCCQLPVMQEPGCTMGIC-SSCNFAFCTLCRLTYH 345
Cdd:cd20340    10 EQYERYQRFGAEECVLQMGGVL-CPQPGCGAGLLPEDECNRVTCeLGCGFVFCRECLEAYH 69

Modified RING finger, HC subclass (C4C4-type), found in RING finger protein 144B (RNF144B); RNF144B, also known as PIR2, IBR domain-containing protein 2 (IBRDC2), or p53-inducible RING finger protein (p53RFP), is a transmembrane (TM) domain-containing RBR (RING1-IBR-RING2) E3 ubiquitin-protein ligase that 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. RNF144B contains 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 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 C4C4-type RING finger whose overall folding is similar to that of the C3HC4-type RING-HC finger. It is required for RBR-mediated ubiquitination.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 2217357919 219 LCSICFCEKLGSECMYFLECRHVYCKACLKDYFEIQIRDGQVQCLNCPEPKC 270
Cdd:cd16778     2 TCKLCLCEHPFDAMTTLQECDCVFCTPCLKQYVQLAIREGCGSPITCPDMAC 53

Modified RING finger, HC subclass (C4C4-type), found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also known as 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 the 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 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 C4C4-type RING finger motif whose overall folding is similar to that of the C3HC4-type RING-HC finger. It is required for RBR-mediated ubiquitination.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2217357919 220 CSICFCEKLGSECMYFLECRHVYCKACLKDYFEIQIRDGQVQCLNCP 266
Cdd:cd16631     3 CPICFNSFPRNKMVSLTSCECKICPDCFKQYFTVVIKEKHIRDLVCP 49