Baculoviral inhibition of apoptosis protein repeat; Domain found in inhibitor of apoptosis proteins (IAPs) and other proteins. Acts as a direct inhibitor of caspase enzymes.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 24664975     44 EETRLKTFTDWP-LDWLDKRQLAQTGMYFTHAGDKVKCFFCGVEIGCWEQEDQPVPEHQRWSPNCPLLRR 112
Cdd:smart00238   2 EEARLKTFQNWPyNSKCTPEQLAEAGFYYTGVGDEVKCFFCGGELDNWEPGDDPWEEHKKWSPNCPFVRN 71

Baculoviral inhibition of apoptosis protein repeat domain; Found in inhibitors of apoptosis proteins (IAPs) and other proteins. In higher eukaryotes, BIR domains inhibit apoptosis by acting as direct inhibitors of the caspase family of protease enzymes. In yeast, BIR domains are involved in regulating cytokinesis. This novel fold is stabilized by zinc tetrahedrally coordinated by one histidine and three cysteine residues and resembles a classical zinc finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 24664975 228 ARLRTFEAWPRNLKQKPHQLAEAGFFYTGVGDRVRCFSCGGGLMDWNDNDEPWEQHALWLSQCRFVKL 295
Cdd:cd00022   2 ARLKTFKNWPISLKVTPEKLAEAGFYYTGRGDEVKCFFCGLELKNWEPGDDPWEEHKRWSPNCPFVLL 69

Baculoviral inhibition of apoptosis protein repeat domain; Found in inhibitors of apoptosis proteins (IAPs) and other proteins. In higher eukaryotes, BIR domains inhibit apoptosis by acting as direct inhibitors of the caspase family of protease enzymes. In yeast, BIR domains are involved in regulating cytokinesis. This novel fold is stabilized by zinc tetrahedrally coordinated by one histidine and three cysteine residues and resembles a classical zinc finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 24664975  45 ETRLKTFTDWPLD-WLDKRQLAQTGMYFTHAGDKVKCFFCGVEIGCWEQEDQPVPEHQRWSPNCPLLR 111
Cdd:cd00022   1 EARLKTFKNWPISlKVTPEKLAEAGFYYTGRGDEVKCFFCGLELKNWEPGDDPWEEHKRWSPNCPFVL 68

Inhibitor of Apoptosis domain; BIR stands for 'Baculovirus Inhibitor of apoptosis protein Repeat'. It is found repeated in inhibitor of apoptosis proteins (IAPs), and in fact it is also known as IAP repeat. These domains characteriztically have a number of invariant residues, including 3 conserved cysteines and one conserved histidine that coordinate a zinc ion. They are usually made up of 4-5 alpha helices and a three-stranded beta-sheet. BIR is also found in other proteins known as BIR-domain-containing proteins (BIRPs), such as Survivin.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 24664975    47 RLKTFTDWPLD---WLDKRQLAQTGMYFTHAGDKVKCFFCGVEIGCWEQEDQPVPEHQRWSPNCPLLR 111
Cdd:pfam00653   1 RLATFENWPHSnksPPTPEELAEAGFYYTGTGDRVQCFYCGLELDGWEEGDDPWEEHKKHSPDCPFLK 68

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 24664975   387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSV----TKCPLCRKPFTDV 432
Cdd:pfam13920   1 EDLLCVICLDRPRNVVLLPCGHLCLCEECAERLlrkkKKCPICRQPIESV 50

N1R/p28-like protein; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 24664975  387 EEKLCKIC----YGAEYNTAF---LP-CGHVVaCAKCAS----SVTKCPLCRKPFTDVMRVYF 437
Cdd:PHA02929 173 KDKECAICmekvYDKEIKNMYfgiLSnCNHVF-CIECIDiwkkEKNTCPVCRTPFISVIKSRF 234

Baculoviral inhibition of apoptosis protein repeat domain; Found in inhibitors of apoptosis proteins (IAPs) and other proteins. In higher eukaryotes, BIR domains inhibit apoptosis by acting as direct inhibitors of the caspase family of protease enzymes. In yeast, BIR domains are involved in regulating cytokinesis. This novel fold is stabilized by zinc tetrahedrally coordinated by one histidine and three cysteine residues and resembles a classical zinc finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 24664975 228 ARLRTFEAWPRNLKQKPHQLAEAGFFYTGVGDRVRCFSCGGGLMDWNDNDEPWEQHALWLSQCRFVKL 295
Cdd:cd00022   2 ARLKTFKNWPISLKVTPEKLAEAGFYYTGRGDEVKCFFCGLELKNWEPGDDPWEEHKRWSPNCPFVLL 69

Baculoviral inhibition of apoptosis protein repeat domain; Found in inhibitors of apoptosis proteins (IAPs) and other proteins. In higher eukaryotes, BIR domains inhibit apoptosis by acting as direct inhibitors of the caspase family of protease enzymes. In yeast, BIR domains are involved in regulating cytokinesis. This novel fold is stabilized by zinc tetrahedrally coordinated by one histidine and three cysteine residues and resembles a classical zinc finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 24664975  45 ETRLKTFTDWPLD-WLDKRQLAQTGMYFTHAGDKVKCFFCGVEIGCWEQEDQPVPEHQRWSPNCPLLR 111
Cdd:cd00022   1 EARLKTFKNWPISlKVTPEKLAEAGFYYTGRGDEVKCFFCGLELKNWEPGDDPWEEHKRWSPNCPFVL 68

Inhibitor of Apoptosis domain; BIR stands for 'Baculovirus Inhibitor of apoptosis protein Repeat'. It is found repeated in inhibitor of apoptosis proteins (IAPs), and in fact it is also known as IAP repeat. These domains characteriztically have a number of invariant residues, including 3 conserved cysteines and one conserved histidine that coordinate a zinc ion. They are usually made up of 4-5 alpha helices and a three-stranded beta-sheet. BIR is also found in other proteins known as BIR-domain-containing proteins (BIRPs), such as Survivin.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 24664975    47 RLKTFTDWPLD---WLDKRQLAQTGMYFTHAGDKVKCFFCGVEIGCWEQEDQPVPEHQRWSPNCPLLR 111
Cdd:pfam00653   1 RLATFENWPHSnksPPTPEELAEAGFYYTGTGDRVQCFYCGLELDGWEEGDDPWEEHKKHSPDCPFLK 68

RING finger, HC subclass, found in E3 ubiquitin-protein ligase XIAP, baculoviral IAP repeat-containing protein 8 (BIRC8) and similar proteins; XIAP, also known as baculoviral IAP repeat-containing protein 4 (BIRC4), IAP-like protein (ILP), inhibitor of apoptosis protein 3 (IAP-3), or X-linked inhibitor of apoptosis protein (X-linked IAP), is a potent suppressor of apoptosis that directly inhibits specific members of the caspase family of cysteine proteases, including caspase-3, -7, and -9. It promotes proteasomal degradation of caspase-3 and enhances its anti-apoptotic effect in Fas-induced cell death. The ubiquitin-protein ligase (E3) activity of XIAP also exhibits in the ubiquitination of second mitochondria-derived activator of caspases (Smac). The mitochondrial proteins, Smac/DIABLO and Omi/HtrA2, can inhibit the antiapoptotic activity of XIAP. XIAP has also been implicated in several intracellular signaling cascades involved in the cellular response to stress, such as the c-Jun N-terminal kinase (JNK), the nuclear factor-kappaB (NF-kappaB), and the transforming growth factor-beta (TGF-beta) pathways. Moreover, XIAP can regulate copper homeostasis by interacting with MURR1. BIRC8, also known as inhibitor of apoptosis-like protein 2, IAP-like protein 2, ILP-2, or testis-specific inhibitor of apoptosis, is a tissue-specific homolog of E3 ubiquitin-protein ligase XIAP. It has been implicated in the control of apoptosis in the testis by direct inhibition of caspase 9. Both XIAP and BIRC8 contain three N-terminal baculoviral IAP repeat (BIR) domains, a ubiquitin-association (UBA) domain and a C3HC4-type RING-HC finger at the carboxyl terminus.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 24664975 387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCRKPFTDVMRVYFS 438
Cdd:cd16714  13 EEKLCKICMDRNISIVFIPCGHLVTCKQCAEALDKCPICCTVITFKQKIFMS 64

RING finger, HC subclass, found in apoptosis protein c-IAP1, c-IAP2, livin, and similar proteins; The cellular inhibitor of apoptosis protein c-IAPs function as ubiquitin E3 ligases that mediate the ubiquitination of substrates involved in apoptosis, nuclear factor-kappaB (NF-kappaB) signaling, and oncogenesis. Unlike other IAPs, such as XIAP, c-IAPs exhibit minimal binding to caspases and may not play an important role in the inhibition of these proteases. c-IAP1, also known as baculoviral IAP repeat-containing protein BIRC2, IAP-2, RING finger protein 48, or TNFR2-TRAF-signaling complex protein 2, is a potent regulator of the tumor necrosis factor (TNF) receptor family and NF-kappaB signaling pathways in the cytoplasm. It can also regulate E2F1 transcription factor-mediated control of cyclin transcription in the nucleus. c-IAP2, also known as BIRC3, IAP-1, apoptosis inhibitor 2 (API2), or IAP homolog C, also influences ubiquitin-dependent pathways that modulate innate immune signalling by activation of NF-kappaB. c-IAPs contain three N-terminal baculoviral IAP repeat (BIR) domains that enable interactions with proteins, a ubiquitin-association (UBA) domain that is responsible for the binding of polyubiquitin (polyUb), a caspase activation and recruitment domain (CARD) that serves as a protein interaction surface, and a C3HC4-type RING-HC finger at the carboxyl terminus that is required for ubiquitin ligase activity. Livin, also known as baculoviral IAP repeat-containing protein 7 (BIRC7), kidney inhibitor of apoptosis protein (KIAP), melanoma inhibitor of apoptosis protein (ML-IAP), or RING finger protein 50, was identified as the melanoma IAP. It plays crucial roles in apoptosis, cell proliferation, and cell cycle control. Its anti-apoptotic activity is regulated by the inhibition of caspase-3, -7, and -9. Its E3 ubiquitin-ligase-like activity promotes degradation of Smac/DIABLO, a critical endogenous regulator of all IAPs. Unlike other family members, mammalian livin contains a single BIR domain and a C3HC4-type RING-HC finger. The UBA domain can be detected in non-mammalian homologs of livin.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 24664975 387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCRKPFTDVMRVYFS 438
Cdd:cd16713   6 EERTCKVCMDKEVSIVFIPCGHLVVCTECAPSLRKCPICRATIKGTVRTFLS 57

Modified RING finger, HC subclass (C3HC5-type), found in neuralized-like protein NEURL1A, NEURL1B, and similar proteins; This subfamily includes Drosophila neuralized (D-neu) protein, and its two mammalian homologs, NEURL1A and NEURL1B. D-neu is a regulator of the developmentally important Notch signaling pathway. NEURL1A, also known as NEURL1, NEU, neuralized 1, or RING finger protein 67 (RNF67), is a mammalian homolog of D-neu. It functions as an E3 ubiquitin-protein ligase that directly interacts with and monoubiquitinates cytoplasmic polyadenylation element-binding protein 3 (CPEB3), an RNA binding protein and a translational regulator of local protein synthesis, which facilitates hippocampal plasticity and hippocampal-dependent memory storage. It also acts as a potential tumor suppressor that causes apoptosis and downregulates Notch target genes in medulloblastoma. NEURL1B, also known as neuralized-2 (NEUR2) or neuralized-like protein 3, is another mammalian homolog of D-neu protein. It functions as an E3 ubiquitin-protein ligase that interacts with and ubiquitinates Delta. Thus, it plays a role in the endocytic pathways for Notch signaling by working cooperatively with another E3 ligase, Mind bomb-1 (Mib1), in Delta endocytosis to hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs)-positive vesicles. Members of this subfamily contain two neuralized homology regions (NHRs) responsible for Neural-ligand interactions and a modified C3HC5-type RING-HC finger required for ubiquitin ligase activity. The C3HC5-type RING-HC finger is distinguished from typical C3HC4-type RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSV----TKCPLCRKPFTDVMRVY 436
Cdd:cd16647   4 CVICYERPVDTVLYRCGHMCMCYDCALQLkrrgGSCPICRAPIKDVIKIY 53

RING finger, HC subclass, found in myosin regulatory light chain interacting protein (MYLIP) and similar proteins; MYLIP, also known as inducible degrader of the low-density lipoprotein (LDL)-receptor (IDOL), or MIR, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of myosin regulatory light chain (MRLC), LDLR, VLDLR, and LRP8. Its activity depends on E2 ubiquitin-conjugating enzymes of the UBE2D family. MYLIP stimulates clathrin-independent endocytosis and acts as a sterol-dependent inhibitor of cellular cholesterol uptake by binding directly to the cytoplasmic tail of the LDLR and promoting its ubiquitination via the UBE2D1/E1 complex. The ubiquitinated LDLR then enters the multivesicular body (MVB) protein-sorting pathway and is shuttled to the lysosome for degradation. Moreover, MYLIP has been identified as a novel ERM-like protein that affects cytoskeleton interactions regulating cell motility, such as neurite outgrowth. The ERM proteins includes ezrin, radixin, and moesin, which are cytoskeletal effector proteins linking actin to membrane-bound proteins at the cell surface. MYLIP contains an ERM-homology domain and a C-terminal C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 24664975 387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCRKPFTDVMRVY 436
Cdd:cd16523   1 EAMLCMVCCEEEINSAFCPCGHMVCCESCAAQLQSCPVCRSRVEHVQHVY 50

RING finger, HC subclass, found in caspases-8 and -10-associated RING finger protein 2 (CARP-2) and similar proteins; CARP-2, also known as rififylin, caspase regulator CARP2, FYVE-RING finger protein Sakura (Fring), RING finger and FYVE-like domain-containing protein 1, RING finger protein 189 (RNF189), or RING finger protein 34-like, is an endosome-associated E3 ubiquitin-protein ligase that targets internalized receptor interacting kinase (RIP) for proteasome-mediated degradation. It acts as a negative regulator of tumor necrosis factor (TNF)-induced nuclear factor (NF)-kappaB activation. It also regulates the p53 signaling pathway by degrading 14-3-3sigma and stabilizing MDM2. As a caspase regulator, CARP2 does not localize to membranes in the cell and is involved in the negative regulation of apoptosis, specifically targeting two initiator caspases, caspase 8 and caspase 10. CARP2 contains an N-terminal FYVE-like domain and a C-terminal C3HC4-type RING-HC finger domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 24664975 387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCRKPFTDVMRVY 436
Cdd:cd16707   1 DENLCKICMDSPIDCVLLECGHMVTCTKCGKRMSECPICRQYVIRAVHVF 50

RING finger, HC subclass, found in Arabidopsis thaliana protein XB3 homolog 5 (XBAT35) and similar proteins; XBAT35, also known as ankyrin repeat domain and RING finger-containing protein XBAT35, or RING-type E3 ubiquitin transferase XBAT35, has no E3 ubiquitin-protein ligase activity observed when associated with the E2 enzyme UBC8 in vitro. It contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 24664975 387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSVT----KCPLCRKPFTDVMRVY 436
Cdd:cd23129   1 QRDECVVCMDAPRDAVCVPCGHVAGCMSCLKALMqsspLCPICRAPVRQVIKVY 54

Modified RING finger, HC subclass (C3HC5-type), found in RING finger protein 26 (RNF26) and similar proteins; RNF26 is an E3 ubiquitin ligase that temporally regulates virus-triggered type I interferon induction by increasing the stability of Mediator of IRF3 activation, MITA, also known as STING, through K11-linked polyubiquitination of MITA after viral infection, and promoting the degradation of IRF3, another important component required for virus-triggered interferon induction. Although RNF26 substrates of ubiquitination remain unclear at present, RNF26 upregulation in gastric cancer might be implicated in carcinogenesis through dysregulation of growth regulators. RNF26 contains an N-terminal leucine zipper domain and a C-terminal modified C3HC5-type RING-HC finger, which is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 24664975 387 EEKLCKICYGAEYNTAFLPCGHVVACAKCASSVTK-------CPLCRKPFTDVMRVY 436
Cdd:cd16788   4 DKKKCVICQDQSKTVLILPCRHMCLCRQCANILLQqpvyrrnCPLCRTMILQTLDVY 60

Modified RING finger, HC subclass (C3HC5-type), found in neuralized-like protein 1B (NEURL1B); NEURL1B, also known as neuralized-2 (NEUR2) or neuralized-like protein 3, is a mammalian homolog of the Drosophila neuralized (D-neu) protein. It functions as an E3 ubiquitin-protein ligase that interacts with and ubiquitinates Delta. Thus, it plays a role in the endocytic pathways for Notch signaling through working cooperatively with another E3 ligase, Mind bomb-1 (Mib1), in Delta endocytosis to hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs)-positive vesicles. NEURL1B contains two neuralized homology regions (NHRs) responsible for Neural-ligand interactions and a modified C3HC5-type RING-HC finger required for ubiquitin ligase activity. The C3HC5-type RING-HC finger is distinguished from typical C3HC4-type RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVTK-----CPLCRKPFTDVMRVY 436
Cdd:cd16786   5 CTVCFDSEVDTVIYTCGHMCLCNSCGLKLKRqinacCPICRRVIKDVIKIY 55

RING finger, HC subclass, found in RING finger and SPRY domain-containing protein 1 (RSPRY1) and similar proteins; RSPRY1 is a hypothetical RING and SPRY domain-containing protein of unknown physiological function. Mutations in its corresponding gene RSPRY1 may associate with a distinct skeletal dysplasia syndrome. RSPRY1 contains a B30.2/SPRY domain and a C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 24664975 388 EKLCKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCRKP 428
Cdd:cd16566   2 EDSCTLCFDKVADTELRPCGHSGFCMECALQLETCPLCRQP 42

RING finger, HC subclass, found in RNA-binding protein MEX3B; MEX3B, also known as RING finger and KH domain-containing protein 3 (RKHD3), or RING finger protein 195 (RNF195), is an RNA-binding phosphoprotein that localizes in P-bodies and stress granules, which are two structures involved in the storage and turnover of mRNAs. It regulates the spatial organization of the Rap1 pathway that orchestrates Sertoli cell functions. It has a 3' long conserved untranslated region (3'LCU)-mediated fine-tuning system for mRNA regulation in early vertebrate development such as anteroposterior (AP) patterning and signal transduction. MEX3B contains two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. Like other MEX-3 family proteins, MEX3B shuttles between the nucleus and the cytoplasm via the CRM1-dependent export pathway.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVT-----KCPLCRKPFTDVMRVY 436
Cdd:cd16721   7 CSICFESEVIAALVPCGHNLFCMECANRICeknepQCPVCHAAVTQAIRIF 57

Modified RING finger, HC subclass (C3HC5-type), found in mahogunin RING finger protein 1 (MGRN1), RING finger protein 157 (RNF157) and similar proteins; MGRN1, also known as RING finger protein 156 (RNF156), is a cytosolic E3 ubiquitin-protein ligase that inhibits signaling through the G protein-coupled melanocortin receptors-1 (MC1R), -2 (MC2R) and -4 (MC4R) via ubiquitylation-dependent and -independent processes. It suppresses chaperone-associated misfolded protein aggregation and toxicity. MGRN1 interacts with cytosolic prion proteins (PrPs) that are linked with neurodegeneration. It also interacts with expanded polyglutamine proteins, and suppresses misfolded polyglutamine aggregation and cytotoxicity. Moreover, MGRN1 inhibits melanocortin receptor signaling by competition with Galphas, suggesting a novel pathway for melanocortin signaling from the cell surface to the nucleus. MGRN1 also interacts with and ubiquitylates TSG101, a key component of the endosomal sorting complex required for transport (ESCRT)-I, and regulates endosomal trafficking. A null mutation in the gene encoding MGRN1 causes spongiform neurodegeneration, suggesting a link between dysregulation of endosomal trafficking and spongiform neurodegeneration. RNF157 is a cytoplasmic E3 ubiquitin ligase predominantly expressed in the brain. It is a homolog of the E3 ligase mahogunin ring finger-1 (MGRN1). In cultured neurons, it promotes neuronal survival in an E3 ligase-dependent manner. In contrast, it supports growth and maintenance of dendrites independent of its E3 ligase activity. RNF157 interacts with and ubiquitinates the adaptor protein APBB1 (amyloid beta precursor protein-binding, family B, member 1 or Fe65), which regulates neuronal survival, but not dendritic growth downstream of RNF157. The nuclear localization of APBB1 together with its interaction partner RNA-binding protein SART3 (squamous cell carcinoma antigen recognized by T cells 3 or Tip110) is crucial to trigger apoptosis. Both MGRN1 and RNF157 contain a modified C3HC5-type RING-HC finger, and a functionally uncharacterized region, known as domain associated with RING2 (DAR2), N-terminal to the RING finger. The C3HC5-type RING-HC finger is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 24664975 389 KLCKICYGAEYNTAFLPCGHVVACAKCASSV----TKCPLCR 426
Cdd:cd16789   1 SECVICLSDPRDTAVLPCRHLCLCSDCAEVLryqsNKCPICR 42

first RING finger, HC subclass, found in mind bomb 1 (MIB1) and similar proteins; MIB1, also known as DAPK-interacting protein 1 (DIP-1) or zinc finger ZZ type with ankyrin repeat domain protein 2, is a large, multi-domain E3 ubiquitin-protein ligase that promotes ubiquitination of the cytoplasmic tails of Notch ligands, and thus plays an essential role in controlling metazoan development by Notch signaling. It is also involved in Wnt/beta-catenin signaling and nuclear factor (NF)-kappaB signaling, and has been implicated in innate immunity, neuronal function, genomic stability, and cell death. MIB1 contains an MZM region with two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region consisting of three C3HC4-type RING-HC fingers. This model corresponds to the first RING-HC finger.

                        10        20        30
                ....*....|....*....|....*....|....*.
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCR 426
Cdd:cd16724   3 CMVCSDMKRDTLFGPCGHIATCSLCSPRVKKCLICK 38

HC subclass of RING (RING-HC) finger and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers. Some have a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle, and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 24664975 391 CKICYGAEYNTAFLPCGHVVaCAKCA-----SSVTKCPLC 425
Cdd:cd16449   3 CPICLERLKDPVLLPCGHVF-CRECIrrlleSGSIKCPIC 41

RING finger, HC subclass, found in mind bomb MIB1, MIB2, and similar proteins; MIBs are large, multi-domain E3 ubiquitin-protein ligases that promote ubiquitination of the cytoplasmic tails of Notch ligands. They are also responsible for TBK1 K63-linked ubiquitination and activation, promoting interferon production and controlling antiviral immunity. Moreover, MIBs selectively control responses to cytosolic RNA and regulate type I interferon transcription. Both MIB1 and MIB2 have similar domain architectures, which consist of two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region, where MIB1 and MIB2 contain three and two C3HC4-type RING-HC fingers, respectively. This model corresponds to the first RING-HC finger of MIB1 and MIB2, as well as the second RING-HC finger of MIB1.

                        10        20        30
                ....*....|....*....|....*....|....*.
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLCR 426
Cdd:cd16519   3 CRVCSDKKALVLFQPCGHVVACEECSLRMKKCLQCK 38

RING finger, HC subclass, found in RNA-binding protein MEX3A; MEX3A, also known as RING finger and KH domain-containing protein 4 (RKHD4), is an RNA-binding phosphoprotein that localizes in P-bodies and stress granules, which are two structures involved in the storage and turnover of mRNAs. It has been implicated in the regulation of tumorigenesis. It controls the polarity and stemness of intestinal epithelial cells through the post-transcriptional regulation of the homeobox transcription factor CDX2, which plays a crucial role in intestinal cell fate specification, both during normal development and in tumorigenic processes involving intestinal reprogramming. Moreover, it exhibits a transforming activity when overexpressed in gastric epithelial cells. MEX3A contains two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. Like other MEX-3 family proteins, MEX3A shuttles between the nucleus and the cytoplasm via the CRM1-dependent export pathway.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVT-----KCPLCRKPFTDVMRVY 436
Cdd:cd16720   5 CMVCFESEVTAALVPCGHNLFCMECAVRICernepECPVCHALATQAIRIF 55

RING finger, HC subclass, found in RNA-binding protein MEX3D; MEX3D, also known as RING finger and KH domain-containing protein 1 (RKHD1), RING finger protein 193 (RNF193), or TINO, is an RNA-binding phosphoprotein that controls the stability of the transcripts coding for the anti-apoptotic protein BCL-2, and negatively regulates BCL-2 in HeLa cells. MEX3D contains two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. Like other MEX-3 family proteins, MEX3D shuttles between the nucleus and the cytoplasm via the CRM1-dependent export pathway.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 24664975 377 TNSSGSTSIPEEklCKICYGAEYNTAFLPCGHVVACAKCA-----SSVTKCPLCRKPFTDVMRVY 436
Cdd:cd16723   1 SSSDGARKSARE--CVVCFESEVIAALVPCGHNLFCMECAiricgKSEPECPACHTPATQAIHIF 63

RING finger, HC subclass, found in RNA-binding protein MEX3C; MEX3C, also known as RING finger and KH domain-containing protein 2 (RKHD2), or RING finger protein 194 (RNF194), is an RNA-binding phosphoprotein that acts as a suppressor of chromosomal instability. It functions as an ubiquitin E3 ligase responsible for the post-transcriptional, HLA-A allotype-specific regulation of MHC class I molecules (MHC-I). It also modifies retinoic acid inducible gene-1 (RIG-I) in stress granules and plays a critical role in eliciting antiviral immune responses. Moreover, MEX3C plays an essential role in normal postnatal growth via enhancing the local expression of insulin-like growth factor 1 (IGF1) in bone. It may also be involved in metabolic regulation of energy balance. MEX3C contains two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. Like other MEX-3 family proteins, MEX3C shuttles between the nucleus and the cytoplasm via the CRM1-dependent export pathway.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVTK-----CPLCRKPFTDVMRVY 436
Cdd:cd16722   4 CVICFENEVIAALVPCGHNLFCMECANKICEketpsCPVCQTAVTQAIQIH 54

first RING finger, HC subclass, found in mind bomb 2 (MIB2) and similar proteins; MIB2, also known as novel zinc finger protein (Novelzin), putative NF-kappa-B-activating protein 002N, skeletrophin, or zinc finger ZZ type with ankyrin repeat domain protein 1, is a large, multi-domain E3 ubiquitin-protein ligase that promotes ubiquitination of the cytoplasmic tails of Notch ligands. It promotes Delta ubiquitylation and endocytosis in Notch activation. Overexpression of MIB2 activates NF-kappaB and interferon-stimulated response element (ISRE) reporter activity. Moreover, MIB2 acts as a novel component of the activated B-cell CLL/lymphoma 10 (BCL10) complex and controls BCL10-dependent NF-kappaB activation. It also functions as a founder myoblast-specific protein that regulates myoblast fusion and muscle stability. MIB2 contains an MZM region with two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region consisting of two C3HC4-type RING-HC fingers. This model corresponds to the first RING-HC finger.

                        10        20        30
                ....*....|....*....|....*....|....*
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLC 425
Cdd:cd16726   3 CLVCSELAALVRFEPCQHSIVCEECARRMKKCIKC 37

RING finger, HC subclass, found in Casitas B-lineage lymphoma (Cbl) proteins; The Cbl adaptor protein family contains a small class of RING-type E3 ubiquitin ligases with oncogenic activity, which is represented by three mammalian members, c-Cbl, Cbl-b and Cbl-c, as well as two invertebrate Cbl-family proteins, D-Cbl in Drosophila and Sli-1 in C. elegans. Cbl proteins function as potent negative regulators of various signaling cascades in a wide range of cell types. They play roles in ubiquitinating activated tyrosine kinases and targeting them for degradation. D-Cbl associates with the Drosophila epidermal growth factor receptor (EGFR) and overexpression of D-Cbl in the eye of Drosophila embryos inhibits EGFR-dependent photoreceptor cell development. Sli-1 is a negative regulator of the Let-23 receptor tyrosine kinase, an EGFR homolog, in vulva development. Cbl proteins in this subfamily consist of a highly conserved N-terminal half that includes a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain) and a C3HC4-type RING-HC finger, both of which are required for Cbl-mediated downregulation of RTKs, and a divergent C-terminal region.

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                ....*....|....*....|....*....|....*....|..
gi 24664975 390 LCKICYGAEYNTAFLPCGHVVaCAKC-----ASSVTKCPLCR 426
Cdd:cd16502   3 LCKICAENDKDVRIEPCGHLL-CTPCltswqDSDGQTCPFCR 43

Modified RING finger, HC subclass (C2H2C4-type), found in E3 ubiquitin-protein ligase MDM2 and similar proteins; MDM2, also known as double minute 2 protein (Hdm2), oncoprotein MDM2, or p53-binding protein, exerts its oncogenic activity predominantly by binding p53 tumor suppressor and blocking its transcriptional activity. It forms homo-oligomers and displays E3 ubiquitin ligase activity that catalyzes the attachment of ubiquitin to p53 as an essential step in the regulation of its levels in cells. Moreover, in response to ribosomal stress, MDM2-mediated p53 ubiquitination and degradation can be inhibited through its interaction with ribosomal proteins L5, L11, and L23. MDM2 can be phosphorylated in the DNA damage. Meanwhile, MDM2 has a p53-independent role in tumorigenesis and cell growth regulation. In addition, it binds interferon (IFN) regulatory factor-2 (IRF-2), an IFN-regulated transcription factor, and mediates its ubiquitination. MDM2 contains an N-terminal p53-binding domain, and a C-terminal modified C2H2C4-type RING-HC finger conferring E3 ligase activity that is required for ubiquitination and nuclear export of p53. It is also responsible for the hetero-oligomerization of MDM2, which is crucial for the suppression of P53 activity during embryonic development, and the recruitment of E2 ubiquitin-conjugating enzymes. MDM2 also harbors a RanBP2-type zinc finger (zf-RanBP2) domain, as well as a nuclear localization signal (NLS) and a nuclear export signal (NES), near the central acidic region. The zf-RanBP2 domain plays an important role in mediating MDM2 binding to ribosomal proteins and thus is involved in MDM2-mediated p53 suppression.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 24664975 391 CKICYGAEYNTAFL--PCGHVVACAKCASSVTK----CPLCRKPFTDVMRVYFS 438
Cdd:cd16783   4 CVICQTRPKNGCIVhgKTGHLMACFTCAKKLKKrnkpCPVCRQPIQMIVLTYFP 57

second RING finger, HC subclass, found in mind bomb 2 (MIB2) and similar proteins; MIB2, also known as novel zinc finger protein (Novelzin), putative NF-kappa-B-activating protein 002N, skeletrophin, or zinc finger ZZ type with ankyrin repeat domain protein 1, is a large, multi-domain E3 ubiquitin-protein ligase that promotes ubiquitination of the cytoplasmic tails of Notch ligands. Especially, it promotes Delta ubiquitylation and endocytosis in Notch activation. Overexpression of MIB2, activates NF-kappaB and interferon-stimulated response element (ISRE) reporter activity. Moreover, MIB2 acts as a novel component of the activated B-cell CLL/lymphoma 10 (BCL10) complex and controls BCL10-dependent NF-kappaB activation. It also functions as a founder myoblast-specific protein that regulates myoblast fusion and muscle stability. MIB2 contains an MZM region with two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region consisting of two C3HC4-type RING-HC fingers. This model corresponds to the second RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 24664975 387 EEKL-CKICYGAEYNTAFlPCGHVvACAKCASSVTKCPLCRKPFTDVMRVY 436
Cdd:cd16728   2 EERItCPICIDNHIKLVF-QCGHG-SCIECSSALKACPICRQAIRERIQIF 50

RING finger, HC subclass, found in RING finger protein unkempt (UNK), unkempt-like (UNKL), and similar proteins; UNK, also known as zinc finger CCCH domain-containing protein 5, is a metazoan-specific zinc finger protein enriched in embryonic brains. It may play a broad regulatory role during the formation of the central nervous system (CNS). It is a sequence-specific RNA-binding protein required for early neuronal morphology. UNK is a neurogenic component of the mTOR pathway, and functions as a negative regulator of the timing of photoreceptor differentiation. It also specifically binds to Brg/Brm-associated factor BAF60b and promotes its ubiquitination in a Rac1-dependent manner. UNKL, also known as zinc finger CCCH domain-containing protein 5-like, is a putative E3 ubiquitin-protein ligase that may participate in a protein complex showing an E3 ligase activity regulated by RAC1. Both UNK and UNKL contain several tandem CCCH-type zinc fingers at the N-terminus, and a C3HC4-type RING-HC finger at its C-terminus.

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                ....*....|....*....|....*....|....*..
gi 24664975 389 KLCKICYGAEYNTAFLPCGHVVACAKCASSVTKCPLC 425
Cdd:cd16614   1 KKCMKCEERNRSVAVLPCQHYVLCEQCAETATECPYC 37

RING-finger-containing E3 ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 24664975 360 TRIFNKIVEATAVATPSTNSS--GSTSIPE-EKLCKICYGAEYNTAFLPCGHVVAC-----AKCASSVTKCPLCR 426
Cdd:COG5574 184 LQPSNNLHTLFQVITKENLSKknGLPFIPLaDYKCFLCLEEPEVPSCTPCGHLFCLsclliSWTKKKYEFCPLCR 258

RING finger, HC subclass, found in topoisomerase I-binding arginine/serine-rich protein (Topors) and similar proteins; Topors, also known as topoisomerase I-binding RING finger protein, tumor suppressor p53- binding protein 3, or p53-binding protein 3 (p53BP3), is a ubiquitously expressed nuclear E3 ubiquitin-protein ligase that can ligate both ubiquitin and small ubiquitin-like modifier (SUMO) to substrate proteins in the nucleus. It contains an N-terminal C3HC4-type RING-HC finger which ligates ubiquitin to its target proteins including DNA topoisomerase I, p53, NKX3.1, H2AX, and the AAV-2 Rep78/68 proteins. As a RING-dependent E3 ubiquitin ligase, Topors works with the E2 enzymes UbcH5a, UbcH5c, and UbcH6, but not with UbcH7, CDC34, or UbcH2b. Topors acts as a tumor suppressor in various malignancies. It regulates p53 modification, suggesting it may be responsible for astrocyte elevated gene-1 (AEG-1, also known as metadherin, or LYRIC) ubiquitin modification. Plk1-mediated phosphorylation of Topors inhibits Topors-mediated sumoylation of p53, whereas p53 ubiquitination is enhanced, leading to p53 degradation. It also functions as a negative regulator of the prostate tumor suppressor NKX3.1. Moreover, Topors is associated with promyelocytic leukemia nuclear bodies, and may be involved in the cellular response to camptothecin. It also plays a key role in the turnover of H2AX protein, discriminating the type of DNA damaging stress. Furthermore, Topors is a cilia-centrosomal protein associated with autosomal dominant retinal degeneration. Mutations in TOPORS cause autosomal dominant retinitis pigmentosa (adRP).

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                ....*....|....*....|....*....|....*....|....*...
gi 24664975 388 EKLCKICYGA-EYNTAFL-PCGHVVaCAKC----ASSVTKCPLCRKPF 429
Cdd:cd16574   1 DSSCPICLDRfENEKAFLdGCFHAF-CFTCilewSKVKNECPLCKQPF 47

Modified RING finger, HC subclass (C3HC5-type), found in mahogunin RING finger protein 1 (MGRN1) and similar proteins; MGRN1, also known as RING finger protein 156 (RNF156), is a cytosolic E3 ubiquitin-protein ligase that inhibits signaling through the G protein-coupled melanocortin receptors-1 (MC1R), -2 (MC2R) and -4 (MC4R) via ubiquitylation-dependent and -independent processes. It suppresses chaperone-associated misfolded protein aggregation and toxicity. MGRN1 interacts with cytosolic prion proteins (PrPs) that are linked with neurodegeneration. It also interacts with expanded polyglutamine proteins, and suppresses misfolded polyglutamine aggregation and cytotoxicity. Moreover, MGRN1 inhibits melanocortin receptor signaling by competition with Galphas, suggesting a novel pathway for melanocortin signaling from the cell surface to the nucleus. Furthermore, MGRN1 interacts with and ubiquitylates TSG101, a key component of the endosomal sorting complex required for transport (ESCRT)-I, and regulates endosomal trafficking. A null mutation in the gene encoding MGRN1 causes spongiform neurodegeneration, suggesting a link between dysregulation of endosomal trafficking and spongiform neurodegeneration. MGRN1 contains a modified C3HC5-type RING-HC finger, a conserved PSAP motif necessary for interaction between MGRN1 and TSG101. In addition, MGRN1 harbors a functionally uncharacterized region, as known as the domain associated with RING2 (DAR2), N-terminal to the RING finger. The C3HC5-type RING-HC finger is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

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                ....*....|....*....|....*....|....*....|....*...
gi 24664975 391 CKICYGAEYNTAFLPCGHVVACAKCASSV----TKCPLCRKPFTDVMR 434
Cdd:cd16816  11 CVVCLSDLRDTLILPCRHLCLCNSCADTLryqaNNCPICRLPFRALLQ 58

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

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                ....*....|....*....|....*....|....*....|....
gi 24664975 391 CKICYGAEYNTAFLP-CGHVVaCAKC-----ASSVTKCPLCRKP 428
Cdd:cd16564   3 CPVCYEDFDDAPRILsCGHSF-CEDClvkqlVSMTISCPICRRV 45

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 24664975 387 EEKLCKICYGAEYNTAFL-PCGHVVaCAKC-------ASSVTKCPLCRKPFTDV 432
Cdd:cd16554   1 ESLTCPVCLDLYYDPYMCyPCGHIF-CEPClrqlaksSPKNTPCPLCRTTIRRV 53

N1R/p28-like protein; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 24664975  387 EEKLCKIC----YGAEYNTAF---LP-CGHVVaCAKCAS----SVTKCPLCRKPFTDVMRVYF 437
Cdd:PHA02929 173 KDKECAICmekvYDKEIKNMYfgiLSnCNHVF-CIECIDiwkkEKNTCPVCRTPFISVIKSRF 234

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 24664975    391 CKICYG-AEYNTAFLPCGHVVaCAKCA-----SSVTKCPLC 425
Cdd:smart00184   1 CPICLEeYLKDPVILPCGHTF-CRSCIrkwleSGNNTCPIC 40

Modified RING finger, HC subclass (C2H2C4-type), found in protein MDM4 and similar proteins; MDM4, also known as double minute 4 protein (Hdm4), MDM2-like p53-binding protein, protein MDMX, HDMX, or p53-binding protein MDM4, exerts its oncogenic activity predominantly by binding p53 tumor suppressor and blocking its transcriptional activity. MDM4 is phosphorylated and destabilized in response to DNA damage stress. It can also be specifically dephosphorylated by directly interacting with protein phosphatase 1 (PP1), which may increase its stability and thus inhibit p53 activity. Meanwhile, MDM4 has a p53-independent role in tumorigenesis and cell growth regulation. MDM4 contains an N-terminal p53-binding domain and a C-terminal modified C2H2C4-type RING-HC finger responsible for its hetero-oligomerization, which is crucial for the suppression of P53 activity during embryonic development and the recruitment of E2 ubiquitin-conjugating enzymes. MDM4 also harbors a RanBP2-type zinc finger (zf-RanBP2) domain near the central acidic region.

                        10        20        30
                ....*....|....*....|....*....|....
gi 24664975 407 GHVVACAKCASSVTK----CPLCRKPFTDVMRVY 436
Cdd:cd16784  24 AHLVTCFHCARRLKKagapCPVCKKEIQMVIKIF 57