BRcat domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1 is also called RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28). Together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), it forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 HOIL1 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 145046239 359 AENRSTLSYHCKTPDCRGWCFFEDDVNEFTCPVCTRVNCLLCKAIHEHMNCREYQDDLALRAQND 423
Cdd:cd20345    1 AESRSPNSFHCKTPDCPGWCFYEDDVNEFLCPVCKHTNCLTCKAIHEGMNCKEYQDDLRLRANND 65

Modified RING finger, HC subclass (C3HC3D-type), found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also known as RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), form the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta, but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to the RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 modified C3HC3D-type RING-HC finger required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 145046239 271 LVLNTEPTECPVCYSVLAPGEAVVLRECLHTFCRECLQGTIRNSQEAEVACPFIDS 326
Cdd:cd16633    1 LVPNQEPFECPICFDDVPPGEGVVLRECLHSFCRECLRGAIQNSEEAEVKCPFRDD 56

BRcat domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1 is also called RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28). Together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), it forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 HOIL1 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 145046239 359 AENRSTLSYHCKTPDCRGWCFFEDDVNEFTCPVCTRVNCLLCKAIHEHMNCREYQDDLALRAQND 423
Cdd:cd20345    1 AESRSPNSFHCKTPDCPGWCFYEDDVNEFLCPVCKHTNCLTCKAIHEGMNCKEYQDDLRLRANND 65

Modified RING finger, HC subclass (C3HC3D-type), found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also known as RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), form the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta, but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to the RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 modified C3HC3D-type RING-HC finger required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 145046239 271 LVLNTEPTECPVCYSVLAPGEAVVLRECLHTFCRECLQGTIRNSQEAEVACPFIDS 326
Cdd:cd16633    1 LVPNQEPFECPICFDDVPPGEGVVLRECLHSFCRECLRGAIQNSEEAEVKCPFRDD 56

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 145046239  278 TECPVCYSVLAPGEAVVLRECLHTFCRECLQGTIRNSQEaevaCPF 323
Cdd:pfam13639   1 DECPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRSSNT----CPL 42

BRcat domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1 is also called RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28). Together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), it forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 HOIL1 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 145046239 359 AENRSTLSYHCKTPDCRGWCFFEDDVNEFTCPVCTRVNCLLCKAIHEHMNCREYQDDLALRAQND 423
Cdd:cd20345    1 AESRSPNSFHCKTPDCPGWCFYEDDVNEFLCPVCKHTNCLTCKAIHEGMNCKEYQDDLRLRANND 65

Modified RING finger, HC subclass (C3HC3D-type), found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also known as RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), form the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta, but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to the RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 modified C3HC3D-type RING-HC finger required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 145046239 271 LVLNTEPTECPVCYSVLAPGEAVVLRECLHTFCRECLQGTIRNSQEAEVACPFIDS 326
Cdd:cd16633    1 LVPNQEPFECPICFDDVPPGEGVVLRECLHSFCRECLRGAIQNSEEAEVKCPFRDD 56

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

                         10        20        30
                 ....*....|....*....|....*....|...
gi 145046239 441 EAMHCPQCRIVVQKKDGCDWIRCTVCHTEICWV 473
Cdd:cd20336    1 NTKKCPKCKVPIEKNGGCNHMTCSRCGTEFCWL 33

Rcat domain found in RING finger protein 217 (RNF217); RNF217, also called IBR domain-containing protein 1 (IBRDC1), is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase, with different splice variants, that is mainly expressed in testis and skeletal muscle. It interacts with the anti-apoptotic protein HAX1, and is adjacent to a translocation breakpoint involving ETV6 in childhood acute lymphoblastic leukemia (ALL). RNF217 contains an RBR domain followed by 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 RNF217 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 145046239 439 QGEAMHCPQCRIVVQKKDGCDWIRCTVCHTEICW 472
Cdd:cd20350    2 QRNAQKCPKCKVYIQRSEGCDHMTCSQCNTNFCY 35

Rcat 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 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 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 RNF14 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20
                 ....*....|....*....|....*....
gi 145046239 445 CPQCRIVVQKKDGCDWIRCTVCHTEICWV 473
Cdd:cd20354   16 CPGCGTLIEKIDGCNKMTCTKCRTYFCWL 44

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
                 ....*....|....*....|....*....|....*....|....*...
gi 145046239 368 HCKTPDCRGWCFFEDDV--NEFTCPVCTRVNCLLCKAI-HEHMNCREY 412
Cdd:cd20335    6 WCPTPDCGGVIRVEEPGdgPRVTCPSCGTSFCFKCKEEwHEGLTCEEY 53

ubiquitin-like (Ubl) domain found in the eukaryotic Ddi1 family; The eukaryotic Ddi1 family, including yeast aspartyl protease DNA-damage inducible 1 (Ddi1) and Ddi1-like proteins from vertebrates and other eukaryotes, has been characterized by containing an N-terminal ubiquitin-like (Ubl) domain and a conserved retroviral aspartyl-protease-like domain (RVP) that is important in cell-cycle control. Yeast Ddi1 and many family members also contain a C-terminal ubiquitin-association (UBA) domain, however, Ddi1-like proteins from all vertebrates lack the UBA domain. Ddi1, also termed v-SNARE-master 1 (Vsm1), is an ubiquitin receptor involved in the cell cycle and late secretory pathway in Saccharomyces cerevisiae. It functions as an UBA-Ubl shuttle protein that is required for the proteasome to enable ubiquitin-dependent degradation of its ligands. For instance, Ddi1 plays an essential role in the final stages of proteasomal degradation of Ho endonuclease and of its cognate FBP, Ufo1. Moreover, Ddi1 and its associated protein Rad23p play a cooperative role as negative regulators in yeast PHO pathway. This family also includes mammalian regulatory solute carrier protein family 1 member 1 (RSC1A1), also termed transporter regulator RS1 (RS1), which mediates transcriptional and post-transcriptional regulation of Na(+)-D-glucose cotransporter SGLT1. Ddi1-like proteins play a significant role in cell cycle control, growth control, and trafficking in yeast and may play a crucial role in embryogenesis in higher eukaryotes.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 145046239  73 LTVRPDMTVASLKDMVFLDYGFPPSLQQ-WVVGQRLARDQETLHSHGIrRNGD 124
Cdd:cd01796   16 LEVSPDMTLEDLKALCEAETGIPAAEQVlLHNGQPLTDDKKTLEALGL-KDGD 67

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
                 ....*....|....*....|....*....
gi 145046239 445 CPQCRIVVQKKDGCDWIRCTVCHTEICWV 473
Cdd:cd20360    6 CPKCHVCIEKNGGCNHMQCSKCKHEFCWM 34

RING finger, HC subclass, found in tripartite motif-containing protein 72 (TRIM72) and similar proteins; TRIM72, also known as Mitsugumin-53 (MG53), is a muscle-specific protein that plays a central role in cell membrane repair by nucleating the assembly of the repair machinery at muscle injury sites. It is required in repair of alveolar epithelial cells under plasma membrane stress failure. It interacts with dysferlin to regulate sarcolemmal repair. Upregulation of TRIM72 develops obesity, systemic insulin resistance, dyslipidemia, and hyperglycemia, as well as induces diabetic cardiomyopathy through transcriptional activation of the peroxisome proliferation-activated receptor alpha (PPAR-alpha) signaling pathway. Compensation for the absence of AKT signaling by ERK signaling during TRIM72 overexpression leads to pathological hypertrophy. Moreover, TRIM72 functions as a novel negative feedback regulator of myogenesis by targeting insulin receptor substrate-1 (IRS-1). It is transcriptionally activated by the synergism of myogenin (MyoD) and myocyte enhancer factor 2 (MEF2). TRIM72 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 145046239 280 CPVCYSVLapgEAVVLRECLHTFCRECLQGTIRNSQEAEVACP 322
Cdd:cd16612    7 CPLCLKLF---QSPVTTECGHTFCQDCLSRVPKEEDGGSTSCP 46

RING finger, HC subclass, found in tripartite motif-containing protein 59 (TRIM59) and similar proteins; 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. It is upregulated in gastric cancer and promotes gastric carcinogenesis by interacting with and targeting the P53 tumor suppressor for its ubiquitination and degradation. It also acts as a novel accessory molecule involved in cytotoxicity of BCG-activated macrophages (BAM). Moreover, TRIM59 may serve as a multifunctional regulator for innate immune signaling pathways. It interacts with ECSIT and negatively regulates nuclear factor-kappaB (NF- kappa B) and interferon regulatory factor (IRF)-3/7-mediated signal pathways. TRIM59 belongs 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. In addition, TRIM59 contains a C-terminal transmembrane domain.

                         10        20        30
                 ....*....|....*....|....*....|....*....
gi 145046239 276 EPTECPVCYSVLapgEAVVLRECLHTFCRECLQGTIRNS 314
Cdd:cd16763    2 EDLTCSVCYSLF---EDPRVLPCSHTFCRNCLENILQVS 37

zinc-RING finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 145046239  279 ECPVCYSVLAPGEAVVLRECLHTFCRECLQGTIRNSQeaevaCPF 323
Cdd:pfam14634   1 HCNKCFKELSKTRPFYLTSCGHIFCEECLTRLLQERQ-----CPI 40