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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGGKCPMCQAPVIEVVRAY 836
Cdd:cd16647     4 CVICYERPVDTVLYRCGHMCMCYDCALQLKRRGGSCPICRAPIKDVIKIY 53

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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGGKCPMCQAPVIEVVRAY 836
Cdd:cd16647     4 CVICYERPVDTVLYRCGHMCMCYDCALQLKRRGGSCPICRAPIKDVIKIY 53

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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGGKCPMCQAPVIEVVRAY 836
Cdd:cd16647     4 CVICYERPVDTVLYRCGHMCMCYDCALQLKRRGGSCPICRAPIKDVIKIY 53

RING finger, HC subclass, found in caspases-8 and -10-associated RING finger protein CARP-1, CARP-2 and similar proteins; The CARP subfamily includes CARP-1 and CARP-2 proteins, both of which are E3 ubiquitin ligases that ubiquitinate apical caspases and target them for proteasome-mediated degradation. As a novel group of caspase regulators with a FYVE-type zinc finger domain, they do not localize to membranes in the cell and are involved in the negative regulation of apoptosis, specifically targeting two initiator caspases, caspase 8, and caspase 10. Moreover, they stabilize MDM2 by inhibiting MDM2 self-ubiquitination, as well as by targeting 14-3-3sigma for degradation. They work together with MDM2 to enhance p53 degradation, thereby inhibiting p53-mediated cell death. CARPs contain an N-terminal FYVE-like domain that can serve as a membrane-targeting or endosome localizing signal and a C-terminal C3HC4-type RING-HC finger domain.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEaggkCPMCQAPVIEVVRAY 836
Cdd:cd16500     3 CKICMDAAIDCVLLECGHMVTCTDCGKKLSE----CPICRQYVVRVVHFF 48

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.

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gi 1063705077 786 ICCVCCESNIDSLLYRCGHMNTCEKCAKKLVEaggkCPMCQAPVIEVVRAY 836
Cdd:cd16707     4 LCKICMDSPIDCVLLECGHMVTCTKCGKRMSE----CPICRQYVIRAVHVF 50

Modified RING finger, HC subclass (C3HC5-type), found in neuralized-like protein 1A (NEURL1A) and similar proteins; NEURL1A, also known as NEURL1, NEU, neuralized 1, or RING finger protein 67 (RNF67), is a mammalian homolog of the Drosophila neuralized (D-neu) protein. 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 the medulloblastoma. NEURL1A 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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVE-AGGKCPMCQAPVIEVVRAY 836
Cdd:cd16785     7 CTICYENAVDTVIYTCGHMCLCYACGLRLKKmLNACCPICRRAIKDIIKTY 57

RING finger, HC subclass, found in RNA-binding proteins of the evolutionarily-conserved MEX-3 family; MEX-3 phosphoproteins are found in vertebrates. They are mediators of post-transcriptional regulation in different organisms, and have been implicated in many core biological processes, including embryonic development, epithelial homeostasis, immune responses, metabolism, and cancer. They contain two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. They shuttle between the nucleus and the cytoplasm via the CRM1-dependent export pathway. The RNA-binding protein MEX-3 from nematode Caenorhabditis elegans is the founding member of the MEX-3 family. Due to the lack of a RING-HC finger, it is not included here.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVE-AGGKCPMCQAPVIEVVRAY 836
Cdd:cd16518     3 CVVCFESEVVAALVPCGHNLFCMECANRICEkSDPECPVCHTPVTQAIRIF 53

RING finger, HC subclass, found in caspases-8 and -10-associated RING finger protein 1 (CARP1) and similar proteins; CARP1, also known as caspase regulator CARP1, FYVE-RING finger protein Momo, RING finger homologous to inhibitor of apoptosis protein (RFI), RING finger protein 34 (RNF34), or RING finger protein RIFF, is a nuclear protein that functions as a specific E3 ubiquitin ligase for the transcriptional coactivator PGC-1alpha, a master regulator of energy metabolism and adaptive thermogenesis in the brown fat cell which negatively regulates brown fat cell metabolism. It is preferentially expressed in esophageal, gastric, and colorectal cancers, suggesting a possible association with the development of digestive tract cancers. It regulates the p53 signaling pathway by degrading 14-3-3 sigma and stabilizing MDM2. CARP1 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. CARP1 contains an N-terminal FYVE-like domain and a C-terminal C3HC4-type RING-HC finger domain.

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gi 1063705077 786 ICCVCCESNIDSLLYRCGHMNTCEKCAKKLVEaggkCPMCQAPVIEVVRAY 836
Cdd:cd16706     6 LCRICMDAVIDCVLLECGHMVTCTKCGKRMSE----CPICRQYVVRAVHVF 52

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.

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gi 1063705077 783 RKGI--CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGG-KCPMCQAPVIEVVRAYS 837
Cdd:cd16721     1 RKGSrdCSICFESEVIAALVPCGHNLFCMECANRICEKNEpQCPVCHAAVTQAIRIFS 58

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.

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gi 1063705077 783 RKGICCVCCESNIDSLLYRCGHMNTCEKCAkklvEAGGKCPMCQAPVIEVVRAY 836
Cdd:cd16714    13 EEKLCKICMDRNISIVFIPCGHLVTCKQCA----EALDKCPICCTVITFKQKIF 62

RING finger, HC subclass, found in mind bomb MIB1, MIB2, RGLG1, RGLG2, 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 third RING-HC finger of MIB1, as well as the second RING-HC finger of MIB2. In addition to MIB1 and MIB2, the RING-HC fingers of RING domain ligase RGLG1, RGLG2 and similar proteins from plant are also included in this model. RGLG1 is a ubiquitously expressed E3 ubiquitin-protein ligase that interacts with UBC13 and, together with UBC13, catalyzes the formation of K63-linked polyubiquitin chains, which is involved in DNA damage repair. RGLG1 mediates the formation of canonical, K48-linked polyubiquitin chains that target proteins for degradation. It also regulates apical dominance by acting on the auxin transport proteins abundance. RGLG1 has overlapping functions with its closest sequelog, RGLG2. They both function as RING E3 ligases that interact with ethylene response factor 53 (ERF53) in the nucleus and negatively regulate the plant drought stress response. All RGLG proteins contain a Von Willebrand factor type A (vWA) domain and a C3HC4-type RING-HC finger.

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gi 1063705077 787 CCVCCESNIDsLLYRCGHMnTCEKCAKKLVeaggKCPMCQAPV 829
Cdd:cd16520     3 CPICMERKKN-VVFLCGHG-TCQKCAEKLK----KCPICRKPI 39

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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGG-KCPMCQAPVIEVVRAYS 837
Cdd:cd16722     4 CVICFENEVIAALVPCGHNLFCMECANKICEKETpSCPVCQTAVTQAIQIHS 55

RING finger, HC subclass, found in inhibitor of apoptosis proteins (IAPs); IAPs are frequently overexpressed in cancer and associated with tumor cell survival, chemoresistance, disease progression, and poor prognosis. They function primarily as negative regulators of cell death. They regulate caspases and apoptosis through the inhibition of specific members of the caspase family of cysteine proteases. In addition, IAPs has been implicated in a multitude of other cellular processes, including inflammatory signalling and immunity, mitogenic kinase signalling, proliferation and mitosis, as well as cell invasion and metastasis. IAPs in this family includes cellular inhibitor of apoptosis protein c-IAP1 (BIRC2) and c-IAP2 (BIRC3), XIAP (BIRC4), BIRC7, and BIRC8, all of which 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), and a C3HC4-type RING-HC finger at the carboxyl terminus that is required for ubiquitin ligase activity. The UBA domain is only absent in mammalian homologs of BIRC7. Moreover, c-IAPs contains an additional caspase activation and recruitment domain (CARD) between the UBA and C3HC4-type RING-HC domains. The CARD domain may serve as a protein interaction surface.

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gi 1063705077 786 ICCVCCESNIDSLLYRCGHMNTCEKCAKKLVeaggKCPMC 825
Cdd:cd16510     3 LCKICMDREVNIVFLPCGHLVTCAQCAASLR----KCPIC 38

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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVeaggKCPMCQAPVIEVVRAY 836
Cdd:cd16713    10 CKVCMDKEVSIVFIPCGHLVVCTECAPSLR----KCPICRATIKGTVRTF 55

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 1063705077 788 CVCCESNIDS---LLYRCGHMNTCEKCAKKLVEAGGKCPMCQAPVIEVVRAY 836
Cdd:cd16783     4 CVICQTRPKNgciVHGKTGHLMACFTCAKKLKKRNKPCPVCRQPIQMIVLTY 55

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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLveagGKCPMCQ 826
Cdd:cd16724     3 CMVCSDMKRDTLFGPCGHIATCSLCSPRV----KKCLICK 38

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.

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gi 1063705077 788 CVCCESNI-DSLLYRCGHMNTCEKCAKKLVEAGGKCPMC 825
Cdd:cd16789     3 CVICLSDPrDTAVLPCRHLCLCSDCAEVLRYQSNKCPIC 41

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.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLveagGKCPMCQ 826
Cdd:cd16726     3 CLVCSELAALVRFEPCQHSIVCEECARRM----KKCIKCQ 38

RING finger, HC subclass, found in neuralized-like protein 3 (NEURL3) and similar proteins; NEURL3, also known as lung-inducible neuralized-related C3HC4 RING domain protein (LINCR), is a novel inflammation-induced E3 ubiquitin-protein ligase encoded by LINCR, a glucocorticoid-attenuated response gene induced in the lung during endotoxemia. It is expressed in alveolar epithelial type II cells, preferentially interacts with the ubiquitin-conjugating enzyme UbcH6, and generates polyubiquitin chains linked via non-canonical lysine residues. Overexpression of NEURL3 in the developing lung epithelium inhibits distal differentiation and induces cystic changes in the Notch signaling pathway. NEURL3 contains an N-terminal neuralized homology repeat (NHR) domain similar to the SPRY (SPla and the RYanodine receptor) domain and a C-terminal C3HC4-type RING-HC finger.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGGKCPMCQAPVIEVV 833
Cdd:cd16552     4 CAICFHHTANTRLVPCGHSHFCGSCAWHIFRDTARCPVCRWQIEEVA 50

third 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 third RING-HC finger.

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gi 1063705077 787 CCVCCESNIDSLLYRCGHmNTCEKCAKKLVEaggkCPMCQAPV 829
Cdd:cd16727     2 MCPVCLDRLKNMIFLCGH-GTCQLCGDRMSE----CPICRKAI 39

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 1063705077 787 CCVCCESNIDSLLYRCGHmNTCEKCAKKLVEAGG-------KCPMC 825
Cdd:cd16581     5 CSICYNIFDDPKILPCSH-TFCKNCLEKLLAASGyyllaslKCPTC 49

RING finger, HC subclass, found in zinc finger protein 598 (ZNF598) and similar proteins; ZNF598 associates with eukaryotic initiation factor 4E (eIF4E) homologous protein from mammals (m4EHP) by binding to Grb10-interacting GYF protein 2 (GIGYF2). The m4EHP-GIGYF2 complex functions as a translational repressor and is essential for normal embryonic development of mammalian. ZNF598 harbors a C3HC4-type RING-HC finger at its N-terminus.

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gi 1063705077 786 ICCVCCESNIDSLLYRCGHmNTCEKCAKKLVEAGGK--CPMCQAPVIEVV 833
Cdd:cd16615     2 TCVICCEEIEYFAVGPCNH-PVCYKCSLRMRVLYKDkyCPICRTELDKVI 50

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.

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gi 1063705077 784 KGICCVCCESNIDSLLYRCGHMNTCEKCAKKLVEAGGK---CPMCQAPVIEVVRAY 836
Cdd:cd16788     5 KKKCVICQDQSKTVLILPCRHMCLCRQCANILLQQPVYrrnCPLCRTMILQTLDVY 60