RING finger, HC subclass, found in RING finger protein 19A (RNF19A) and similar proteins; RNF19A, also known as double ring-finger protein (Dorfin) or p38, is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that localizes to the ubiquitylated inclusions in Parkinson's disease (PD), dementia with Lewy bodies, 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 endoplasmic reticulum-associated degradation (ERAD) pathway, which is related to the pathogenesis of neurodegenerative disorders, such as PD or Alzheimer's disease. RNF19A 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 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 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVNISCPECTERFNP 184
Cdd:cd16775    1 MECPLCLLRHSKDRFPDIMTCHHRSCADCLRQYLRIEISESRVNISCPECSERFNP 56

RING finger, HC subclass, found in RING finger protein 19A (RNF19A) and similar proteins; RNF19A, also known as double ring-finger protein (Dorfin) or p38, is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that localizes to the ubiquitylated inclusions in Parkinson's disease (PD), dementia with Lewy bodies, 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 endoplasmic reticulum-associated degradation (ERAD) pathway, which is related to the pathogenesis of neurodegenerative disorders, such as PD or Alzheimer's disease. RNF19A 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 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 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVNISCPECTERFNP 184
Cdd:cd16775    1 MECPLCLLRHSKDRFPDIMTCHHRSCADCLRQYLRIEISESRVNISCPECSERFNP 56

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 431901761  198 EKYEEFMLRRWLVADPDCRWCPAPDCGYAVI-AFGCASCPKLTCgrEGCGTEFCYHCKQIWHPNQTC 263
Cdd:pfam01485   1 EKYEKLLLKSYVESDPNLKWCPTPDCGYIIElTDGCSNTSHVTC--SKCGHEFCFNCKEEWHEGLTC 65

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

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*...
gi 431901761   131 CPLCLLRHSKDrfPEIMTCHHRSCVDCLRQYLRIEisesrvNISCPEC 178
Cdd:smart00184   1 CPICLEEYLKD--PVILPCGHTFCRSCIRKWLESG------NNTCPIC 40

BRcat 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 (URKL-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 BRcat domain of RNF19B that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 431901761 196 LMEKYEEFMLRRWLVADPDCRWCPAPDCGYAVIAFGCASCPKLTCGREGCGTEFCYHCKQIWHPNQTCDAARQER 270
Cdd:cd20363    1 LMHKYEEFMLRRYLASDPDCRWCPAPDCGYAVIAYGCASCPKLTCEREGCQTEFCYHCKQIWHPNQTCDMARQQR 75

RING finger, HC subclass, found in RING finger protein 19A (RNF19A) and similar proteins; RNF19A, also known as double ring-finger protein (Dorfin) or p38, is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that localizes to the ubiquitylated inclusions in Parkinson's disease (PD), dementia with Lewy bodies, 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 endoplasmic reticulum-associated degradation (ERAD) pathway, which is related to the pathogenesis of neurodegenerative disorders, such as PD or Alzheimer's disease. RNF19A 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 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 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVNISCPECTERFNP 184
Cdd:cd16775    1 MECPLCLLRHSKDRFPDIMTCHHRSCADCLRQYLRIEISESRVNISCPECSERFNP 56

RING finger, HC subclass, found in the family of RING finger proteins RNF19A, RNF19B and similar proteins; The family includes RING finger protein RNF19A and RNF19B, both of which are transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligases. RNF19A, also known as double ring-finger protein (Dorfin) or p38, localizes to the ubiquitylated inclusions in Parkinson's disease (PD), dementia with Lewy bodies, 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 endoplasmic reticulum-associated degradation (ERAD) pathway, which is related to the pathogenesis of neurodegenerative disorders, such as PD or Alzheimer's disease. RNF19B, also known as IBR domain-containing protein 3 or natural killer lytic-associated molecule (NKLAM), plays a role in controlling tumor dissemination and metastasis. It is involved in the cytolytic function of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). It interacts with ubiquitin conjugates UbcH7 and UbcH8, and ubiquitinates uridine kinase like-1 (URKL-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. 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 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 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVNISCPECTERFNP 184
Cdd:cd16629    1 LECPLCLDDLSPEFFPILLSCEHRSCRDCLRQYLTIEISESRVNISCPECSERFHP 56

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 431901761  198 EKYEEFMLRRWLVADPDCRWCPAPDCGYAVI-AFGCASCPKLTCgrEGCGTEFCYHCKQIWHPNQTC 263
Cdd:pfam01485   1 EKYEKLLLKSYVESDPNLKWCPTPDCGYIIElTDGCSNTSHVTC--SKCGHEFCFNCKEEWHEGLTC 65

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        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 431901761 196 LMEKYEEFMLRRWLVADPDCRWCPAPDCGYAVIAFgCASCPKLTCgreGCGTEFCYHCKQIWHPNQTCD 264
Cdd:cd20343    4 VRLKYQHLITNSFVECNRLLKWCPAPDCGHAVKVQ-YPDARPVTC---KCGHTFCFACGENWHEPVKCR 68

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 431901761 212 DPDCRWCPAPDCgyAVIAFGCAS------------CPKltcgregCGTEFCYHCKQIWHPNQTCD 264
Cdd:cd20349    5 DPNRTWCPRAGC--ETVCHVCPPsgsapvtavpvqCPK-------CGLTFCSICKAAWHAGQSCD 60

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 431901761 130 ECPLCLLRHSKDRFPeIMTCHHRSCVDCLRQYLRIEISESR-VNISCPEC 178
Cdd:cd16773    2 TCGVCCEDVPKDELF-SLACGHYFCNDCWKQYLTVKIKDGVsTGIECMAP 50

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 431901761 218 CPAPDC--------GYAVIAFGCASCPKltcgregCGTEFCYHCKQIWHPNQTCD 264
Cdd:cd22582    7 CPNPDCsalmskdeLLEAEDDTPRECPK-------CRRLFCARCKVPWHAGLSCA 54

BRcat 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 pathway 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 (TNF) 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 TNF receptor-1-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. This model corresponds to the BRcat domain of RNF216 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 431901761 218 CPApdCGYAVIaFGCASCPKLTCGREGCGTEFCYHCKQIWHPNQTCDAA 266
Cdd:cd20339    7 CPF--CNYAAI-LDPTEVKVFRCPNPECRKESCRKCKKEWHIPLTCEEV 52

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
                 ....*....|....*....|....*....|....*....|..
gi 431901761 218 CPAPDCGYAVIAFGcaSCPKLTCGrEGCGTEFCYHCKQIWHP 259
Cdd:cd20340   32 CPQPGCGAGLLPED--ECNRVTCE-LGCGFVFCRECLEAYHE 70

Ring finger domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 431901761  129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIeisesrvNISCPEC 178
Cdd:pfam13639   1 DECPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRS-------SNTCPLC 43

Modified RING finger, HC subclass (C4C4-type), found in RNF144 proteins; This group includes RNF144A and RNF144B, both of which are transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligases. RNF144A, also known as UbcM4-interacting protein 4 (UIP4) or ubiquitin-conjugating enzyme 7-interacting protein 4, targets DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and thus promote 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 known as 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 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
                 ....*....|....*....|....*....|....*....|....*....
gi 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVN-ISCP 176
Cdd:cd16632    1 ITCKLCLEEVPLREMYTLQSCGCIFCLQCLKQYVEVLIREGNVSsITCP 49

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

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*...
gi 431901761   131 CPLCLLRHSKDrfPEIMTCHHRSCVDCLRQYLRIEisesrvNISCPEC 178
Cdd:smart00184   1 CPICLEEYLKD--PVILPCGHTFCRSCIRKWLESG------NNTCPIC 40

BRcat 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 BRcat domain of TRIAD1 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

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                 ....*....|....*....|....*....|....*....|....*....|....*
gi 431901761 213 PDCRWCPAPDCGYAViafgCASCPK---LTCGRegCGTEFCYHCKQIWHPNQTCD 264
Cdd:cd20344    7 PQLRFCPGPDCPVVI----RALEPKakrVQCKR--CKTSFCFKCGEDYHAPTDCE 55

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.

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                 ....*....|....*....|....*....|....*....|....*....|..
gi 431901761 127 DFIECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVN-ISCPE 177
Cdd:cd16628    4 KIFTCNICFLDKLGSECMYFKDCGHVYCKECLKEYFEVQIRDGNVTsLNCPE 55

RING finger, HC subclass, found in RING finger protein 152 (RNF152) and similar proteins; RNF152 is a lysosome-anchored E3 ubiquitin-protein ligase involved in apoptosis. It is polyubiquitinated through K48 linkage. It negatively regulates the activation of the mTORC1 pathway by targeting RagA GTPase for K63-linked ubiquitination. It interacts with and ubiquitinates RagA in an amino-acid-sensitive manner. The ubiquitination of RagA recruits its inhibitor GATOR1, a GAP complex for Rag GTPases, to the Rag complex, thereby inactivating mTORC1 signaling. RNF152 contains an N-terminal C3HC4-type RING-HC finger and a C-terminal transmembrane domain, both of which are responsible for its E3 ligase activity.

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                 ....*....|....*....|....*....|....*....|....*....|
gi 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQylrieISESRVNISCPEC 178
Cdd:cd16548    1 LECQICFNYYSPRRRPKLLDCKHTCCSVCLQQ-----MRTSQKDLRCPWC 45

RING finger, HC subclass, found in tripartite motif-containing protein 3 (TRIM3); TRIM3, also known as brain-expressed RING finger protein (BERP), RING finger protein 97 (RNF97), or RING finger protein 22 (RNF22), is an E3 ubiquitin-protein ligase involved in the pathogenesis of various cancers. It functions as a tumor suppressor that regulates asymmetric cell division in glioblastoma. It binds to the cdk inhibitor p21(WAF1/CIP1) and regulates its availability that promotes cyclin D1-cdk4 nuclear accumulation. Moreover, TRIM3 plays an important role in the central nervous system (CNS). It is encoded by the gene BERP (brain-expressed RING finger protein), a unique p53-regulated gene that modulates seizure susceptibility and GABAAR cell surface expression. Furthermore, TRIM3 mediates activity-dependent turnover of postsynaptic density (PSD) scaffold proteins GKAP/SAPAP1 and is a negative regulator of dendritic spine morphology. In addition, TRIM3 may be involved in vesicular trafficking via its association with the cytoskeleton-associated-recycling or transport (CART) complex that is necessary for efficient transferrin receptor recycling, but not for epidermal growth factor receptor (EGFR) degradation. It also regulates the motility of the kinesin superfamily protein KIF21B. TRIM3 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is 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 domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 431901761 128 FIECPLCLLRHskdRFPEIMTCHHRSCVDCLRQYlrieISESRVNISCPEC 178
Cdd:cd16768    4 FLVCSICLDRY---HNPKVLPCLHTFCERCLQNY----IPPQSLTLSCPVC 47

zinc-RING finger domain;

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                  ....*....|....*....|....*....|....*....|....*....
gi 431901761  130 ECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRieisesrvNISCPEC 178
Cdd:pfam14634   1 HCNKCFKELSKTRPFYLTSCGHIFCEECLTRLLQ--------ERQCPIC 41

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 431901761 130 ECPLCLLRHSKDRFPeiMTCHHRSCVDCLRQYLRIEISESRVN--ISCPE--CTER 181
Cdd:cd16625    2 ECPICCDDGELETFS--LECGHEFCVDCYSQYLTSKIKEEGEGcrITCPGekCNLI 55

RING finger, HC subclass, found in makorin-2 (MKRN2) and similar proteins; MKRN2, also known as makorin RING finger protein 2, RING finger protein 62 (RNF62), or HSPC070, is a putative ribonucleoprotein that acts as a neurogenesis inhibitor acting upstream of glycogen synthase kinase-3beta (GSK-3beta) in the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. It also functions in promoting cell proliferation of primary CD34+ progenitor cells and K562 cells, indicating its possible involvement in normal and malignant hematopoiesis. Mammalian MKRN2 contains three N-terminal C3H1-type zinc fingers, a motif rich in Cys and His residues (CH), a C3HC4-type RING-HC finger, and another C3H1-type zinc finger at the C-terminus. The third C3H1-type zinc finger, the CH motif, as well as the RING zinc finger are necessary for its anti-neurogenic activity.

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                 ....*....|....*....|....*....|....*....|....*....|....
gi 431901761 131 CPLCLLR------HSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVNISCPEC 178
Cdd:cd16731    4 CSICMEVvyekasASERRFGILSNCNHTYCLSCIRQWRCAKQFENPIIKSCPEC 57

BRcat 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 BRcat domain of RNF144A that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 431901761 207 RWLVADPdCR-WCPAPDCgYAVIAFGCASC--PKLTCGREgCGTEFCYHCKQIWHPNQTC 263
Cdd:cd20366    2 REVLLDP-CRtWCPSSTC-QAVCQLQEVGLqnPQLVQCKA-CDLEFCSACKANWHPGQGC 58

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.

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                 ....*....|....*....|....*....|....*....|....*....|..
gi 431901761 127 DFIECPLCllrHSKDRFPEIMTCHHRSCVDCLRQYLRIEISESRVNISCPEC 178
Cdd:cd16581    1 EELTCSIC---YNIFDDPKILPCSHTFCKNCLEKLLAASGYYLLASLKCPTC 49

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.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 431901761 129 IECPLCLLRHS-KDRFPEIMTCHHRSCVDCLRQYLRIEISESRVnISCPEC 178
Cdd:cd16555    2 LECKICYNRYDlRQRRPKVLECCHRVCAKCLYKIVDLGDSSPSV-LVCPFC 51

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.

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                 ....*....|....*....|....*....|....*....|....*....|
gi 431901761 129 IECPLCLLRHSKDRFPEIMTCHHRSCVDCLRQYLRIEISES-RVNISCPE 177
Cdd:cd16777    1 VSCKLCLGEYPVEQMTTIAQCQCIFCTLCLKQYVELLIKEGlETAISCPD 50