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 222642141 603 KGTCCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16647    1 GSECVICYERPVDTVLYRCGHMCMCYDCALQLKRRGGSCPICRAPIKDVIKIY 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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 222642141 603 KGTCCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16647    1 GSECVICYERPVDTVLYRCGHMCMCYDCALQLKRRGGSCPICRAPIKDVIKIY 53

N1R/p28-like protein; Provisional

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 222642141 606 CCICC----DTPIDS----LLYRCGHMcTCSKCANELVRSGGKCPLCRAPIIEVIRAYF 656
Cdd:PHA02929 177 CAICMekvyDKEIKNmyfgILSNCNHV-FCIECIDIWKKEKNTCPVCRTPFISVIKSRF 234

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 222642141 603 KGTCCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16647    1 GSECVICYERPVDTVLYRCGHMCMCYDCALQLKRRGGSCPICRAPIKDVIKIY 53

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*
gi 222642141 602 RKGTCCICCDTPIDSLLYRCGHMCTCSKCANELVR-SGGKCPLCRAPIIEVIRAY 655
Cdd:cd16786    1 KNGECTVCFDSEVDTVIYTCGHMCLCNSCGLKLKRqINACCPICRRVIKDVIKIY 55

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 222642141 605 TCCICCDTPIDSLLYRCGHMCTCSKCANELvrsgGKCPLCRAPIIEVIRAY 655
Cdd:cd16500    2 LCKICMDAAIDCVLLECGHMVTCTDCGKKL----SECPICRQYVVRVVHFF 48

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 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELVR-SGGKCPLCRAPIIEVIRAY 655
Cdd:cd16785    7 CTICYENAVDTVIYTCGHMCLCYACGLRLKKmLNACCPICRRAIKDIIKTY 57

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 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGK---CPLCRAPIIEVIRAY 655
Cdd:cd16788    8 CVICQDQSKTVLILPCRHMCLCRQCANILLQQPVYrrnCPLCRTMILQTLDVY 60

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 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGKCPLCR 645
Cdd:cd16789    3 CVICLSDPRDTAVLPCRHLCLCSDCAEVLRYQSNKCPICR 42

RING finger, HC subclass, found in RING finger protein 169 (RNF169) and similar proteins; RNF169 is an uncharacterized E3 ubiquitin-protein ligase paralogous to RNF168. It functions as a negative regulator of the DNA damage signaling cascade. RNF169 recognizes polyubiquitin structures but does not itself contribute to double-strand break (DSB)-induced chromatin ubiquitylation. It contributes to regulation of the DSB repair pathway utilization via functionally competing with recruiting repair factors, 53BP1 and RAP80-BRCA1, for association with RNF168-modified chromatin independent of its catalytic activity, limiting the magnitude of the RNF8/RNF168-dependent signaling response to DSBs. RNF169 contains an N-terminal C3HC4-type RING-HC finger and a C-terminal MIU (motif interacting with ubiquitin) domain.

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                 ....*....|....*....|....*....|....*....|....*.
gi 222642141 605 TCCICCDTPIDSLLYRCGHmCTCSKCANELVR---SGGKCPLCRAP 647
Cdd:cd16551    3 TCAGCLEVPVEPATLPCGH-TLCRGCANRALDaaeAGPTCPRCRAP 47

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 222642141 606 CCICCDTPIDsLLYRCGHmCTCSKCANELVrsggKCPLCRAPI 648
Cdd:cd16520    3 CPICMERKKN-VVFLCGH-GTCQKCAEKLK----KCPICRKPI 39

Modified RING finger, HC subclass (C3HC5-type), found in RING finger proteins, RNF26, RNF197 (CGRRF1), RNF156 (MGRN1), RNF157 and similar proteins; This subfamily corresponds to a group of RING finger proteins containing a 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. Cell growth regulator with RING finger domain protein 1 (CGRRF1), also known as cell growth regulatory gene 19 protein (CGR19) or RING finger protein 197 (RNF197), functions as a novel biomarker to monitor endometrial sensitivity and response to insulin-sensitizing drugs, such as metformin, in the context of obesity. 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 after viral infection and promoting degradation of IRF3, another important component required for virus-triggered interferon induction. Mahogunin ring finger-1 (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. RNF157 is a cytoplasmic E3 ubiquitin ligase predominantly expressed in the brain. It is a homolog of the E3 ligase 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.

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                 ....*....|....*....|....*....|....*....|..
gi 222642141 604 GTCCICCDTPIDSLLYRCGHMCTCSKCANELvrSGGKCPLCR 645
Cdd:cd16649    1 GLCVVCLENPASVLLLPCRHLCLCEVCAKGL--RGKTCPICR 40

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 222642141 602 RKGT--CCICCDTPIDSLLYRCGHMCTCSKCANELV-RSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16721    1 RKGSrdCSICFESEVIAALVPCGHNLFCMECANRICeKNEPQCPVCHAAVTQAIRIF 57

RING finger, HC subclass, found in leucine-rich repeat and sterile alpha motif-containing protein 1 (LRSAM1) and similar proteins; LRSAM1, also known as Tsg101-associated ligase (TAL), or RIFLE, is an E3 ubiquitin-protein ligase that physically associates with, and selectively ubiquitylates, Tsg101, an E2-like molecule that regulates vesicular trafficking processes in yeast and mammals. It regulates a Tsg101-associated complex responsible for the sorting of cargo into cytoplasm-containing vesicles that bud at the multivesicular body and at the plasma membrane. LRSAM1 is a multidomain protein containing an N-terminal leucine-rich repeat (LRR), followed by several recognizable motifs, including an ezrin-radixin-moezin (ERM) domain, a coiled-coil (CC) region, a SAM domain, and a C-terminal C3HC4-type RING-HC finger domain.

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                 ....*....|....*....|....*....|....*....|....*...
gi 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELvrsgGKCPLCRAPIIEVIR 653
Cdd:cd16515    4 CVVCMDAESQVIFLPCGHVCCCQTCSSSL----STCPLCRADITQRVR 47

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 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELV-RSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16518    3 CVVCFESEVVAALVPCGHNLFCMECANRICeKSDPECPVCHTPVTQAIRIF 53

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 222642141 605 TCCICCDTPIDSLLYRCGHMCTCSKCANELVrsggKCPLCRAPIIEVIRAY 655
Cdd:cd16713    9 TCKVCMDKEVSIVFIPCGHLVVCTECAPSLR----KCPICRATIKGTVRTF 55

RING finger, HC subclass, found in helicase-like transcription factor (HLTF) and similar proteins; HLTF, also known as DNA-binding protein/plasminogen activator inhibitor 1 regulator, HIP116, RING finger protein 80, SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A member 3, or sucrose nonfermenting protein 2-like 3, is a yeast RAD5 homolog found in mammals. It has both E3 ubiquitin ligase and DNA helicase activities, and plays a pivotal role in the template-switching pathway of DNA damage tolerance. It is involved in Lys-63-linked poly-ubiquitination of proliferating cell nuclear antigen (PCNA) at Lys-164 and in the regulation of DNA damage tolerance. It shows double-stranded DNA translocase activity with 3'-5' polarity, thereby facilitating regression of the replication fork. HLTF contains an N-terminal HIRAN (HIP116 and RAD5 N-terminal) domain, a SWI/SNF helicase domain that is divided into N- and C-terminal parts by an insertion of a C3HC4-type RING-HC finger involved in the poly-ubiquitination of PCNA.

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gi 222642141 606 CCICCDTPIDSLLYRCGHMcTCSKCANE-LVRSGGKCPLCRAPI 648
Cdd:cd16509    6 CAICLDSLTNPVITPCAHV-FCRRCICEvIQREKAKCPMCRAPL 48

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.

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                 ....*....|....*....|....*....|....*....|....*....|..
gi 222642141 606 CCICCDTPID-SLLY-RCGHMCTCSKCANELVRSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16784    6 CSLCQKRPRNgNIVHgRTAHLVTCFHCARRLKKAGAPCPVCKKEIQMVIKIF 57

Modified RING finger, HC subclass (C3HC5-type), found in RING finger protein 157 (RNF157) and similar proteins; RNF157 is a cytoplasmic E3 ubiquitin ligase predominantly expressed in 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. RNF157 contains 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 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGKCPLCRAP 647
Cdd:cd16817    7 CVVCLSDVRDTLILPCRHLCLCNACADTLRYQANNCPICRLP 48

RING finger, HC subclass, found in RING domain ligase RGLG1, RGLG2 and similar proteins from plant; 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. Members of this subfamily contain a Von Willebrand factor type A (vWA) domain and a C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|
gi 222642141 606 CCICCDTPIDsLLYRCGHMcTCSKCANELVrsggKCPLCRAPIIEVIRAY 655
Cdd:cd16729    5 CPICLSNPKD-MAFGCGHQ-TCCECGQSLT----HCPICRQPITTRIKLY 48

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        40
                 ....*....|....*....|....*....|....*....|
gi 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANeLVRsggKCPLCR 645
Cdd:cd16519    3 CRVCSDKKALVLFQPCGHVVACEECSL-RMK---KCLQCK 38

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
                 ....*....|....*....|....*....|....*....|....*....|....
gi 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCAnelVRSGGK----CPLCRAPIIEVIRAY 655
Cdd:cd16723   13 CVVCFESEVIAALVPCGHNLFCMECA---IRICGKsepeCPACHTPATQAIHIF 63

Zinc finger, C3HC4 type (RING finger); The C3HC4 type zinc-finger (RING finger) is a cysteine-rich domain of 40 to 60 residues that coordinates two zinc ions, and has the consensus sequence: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C where X is any amino acid. Many proteins containing a RING finger play a key role in the ubiquitination pathway.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 222642141  606 CCICCDTPID-SLLYRCGHMCtCSKCANELVRSGG-KCPLC 644
Cdd:pfam00097   1 CPICLEEPKDpVTLLPCGHLF-CSKCIRSWLESGNvTCPLC 40

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 222642141 606 CCICCDTPIDSL---LYRCGHmCTCSKCANELV------RSGGKCPLCRAPI 648
Cdd:cd23131    6 CSICTQEPIEVGevvFTECGH-SFCEDCLLEYIefqnkkKLDLKCPNCREPI 56

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELVRSGGKCPLCRAPIIEV 651
Cdd:cd16552    4 CAICFHHTANTRLVPCGHSHFCGSCAWHIFRDTARCPVCRWQIEEV 49

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 222642141 606 CCICCDTPIDSLLYRCGHMCTCSKCANELV-RSGGKCPLCRAPIIEVIRAY 655
Cdd:cd16720    5 CMVCFESEVTAALVPCGHNLFCMECAVRICeRNEPECPVCHALATQAIRIF 55

RING finger, HC subclass, found in RING finger protein 123 (RNF123) and similar proteins; RNF123, also known as Kip1 ubiquitination-promoting complex protein 1 (KPC1), is an E3 ubiquitin-protein ligase that mediates ubiquitination and proteasomal processing of the nuclear factor-kappaB 1 (NF-kappaB1) precursor p105 to the p50 active subunit that restricts tumor growth. It also regulates degradation of heterochromatin protein 1alpha (HP1alpha) and 1beta (HP1beta) in lamin A/C knock-down cells. Moreover, RNF123, together with Kip1 ubiquitylation-promoting complex 2 (KPC2), forms the Kip1 ubiquitination-promoting complex (KPC), acting as a cytoplasmic ubiquitin ligase that regulates degradation of the cyclin-dependent kinase inhibitor p27 (Kip1) at the G1 phase of the cell cycle. RNF123 may also function as a clinically relevant, peripheral state marker of depression. RNF123 contains a C3HC4-type RING-HC finger at the C-terminus.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 222642141 604 GTCCICCDTPIDSLLYRCGHMcTCSKCANELVRSGGKCPLCRAPI 648
Cdd:cd16541    1 DLCPICYAHPIDAVFLPCGHK-SCRSCINRHLMNNKECFFCKATI 44

RING finger, HC subclass, found in tripartite motif-containing protein TRIM21 and similar proteins; TRIM21, also known as 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A, Ro(SS-A), RING finger protein 81 (RNF81), or Sjoegren syndrome type A antigen (SS-A), is a ubiquitously expressed E3 ubiquitin-protein ligase and a high affinity antibody receptor uniquely expressed in the cytosol of mammalian cells. As a cytosolic Fc receptor, TRIM21 binds the Fc of virus-associated antibodies and targets the complex in the cytosol for proteasomal degradation in a process known as antibody-dependent intracellular neutralization (ADIN), and provides an intracellular immune response to protect host defense against pathogen infection. It shows remarkably broad isotype specificity as it does not only bind IgG, but also IgM and IgA. Moreover, TRIM21 promotes the cytosolic DNA sensor cGAS and the cytosolic RNA sensor RIG-I sensing of viral genomes during infection by antibody-opsonized virus. It stimulates inflammatory signaling and activates innate transcription factors, such as nuclear factor-kappaB (NF-kappaB). TRIM21 also plays an essential role in p62-regulated redox homeostasis, suggesting it may be a viable target for treating pathological conditions resulting from oxidative damage. Furthermore, TRIM21 may have implications for various autoimmune diseases associated with uncontrolled antiviral signaling through the regulation of Nmi-IFI35 complex-mediated inhibition of innate antiviral response. TRIM21 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 222642141 605 TCCICCDTPIDSLLYRCGHmCTCSKCANELVRSGGK-CPLCRAPII 649
Cdd:cd16596   11 TCPICLDPFVEPVSIECGH-SFCQECISQVGKGGGSvCPVCRQRFL 55

RING finger, HC subclass, found in Caenorhabditis elegans BRCA1-associated RING domain protein 1 (CeBARD1) and similar proteins; CeBARD1, also called Ce-BRD-1, Cebrd-1, or RING-type E3 ubiquitin transferase BARD1, is a constituent of the CeBCD complex that possesses E3 ubiquitin-protein ligase activity. It plays a role in triggering cellular responses at damage sites in response to DNA damage that may be induced by ionizing radiation. It protects against chromosome non-disjunction and nuclear fragmentation during meiotic double-strand break repair to ensure sister chromatid recombination and aid chromosome stability. CeBARD1 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 222642141 606 CCICCDTPIDS-LLYRCGHMcTCSKCANELVRSGGKCPLCRAPI 648
Cdd:cd23143    4 CVICSEPQIDTfLLSSCGHI-YCWECFTEFIEKRHMCPSCRFPL 46

RING finger, HC subclass, found in peroxin-10 (PEX10) and similar proteins; PEX10, also known as peroxisome biogenesis factor 10, peroxisomal biogenesis factor 10, peroxisome assembly protein 10, or RING finger protein 69 (RNF69), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It plays an essential role in peroxisome assembly, import of target substrates, and recycling or degradation of protein complexes and amino acids. It is an essential component of the spinal locomotor circuit, and thus its mutations may be involved in peroxisomal biogenesis disorders (PBD). Mutations in human PEX10 also result in autosomal recessive ataxia. Moreover, PEX10 functions as an E3-ubiquitin ligase with an E2, UBCH5C. It mono- or poly-ubiquitinates PEX5, a key player in peroxisomal matrix protein import, in a UBC4-dependent manner, to control PEX5 receptor recycling or degradation. It also links the E2 ubiquitin conjugating enzyme PEX4 to the protein import machinery of the peroxisome.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 222642141 606 CCICCDTPIDSLLYRCGHMcTCSKCANELVRSGGKCPLCRAPI 648
Cdd:cd16527    3 CSLCLEERRHPTATPCGHL-FCWSCITEWCNEKPECPLCREPF 44

RING finger, HC subclass, found in Saccharomyces cerevisiae DNA repair protein RAD16, Schizosaccharomyces pombe rhp16, and similar proteins; Budding yeast RAD16, also known as ATP-dependent helicase RAD16, is encoded by a yeast excision repair gene homologous to the recombinational repair gene RAD54 and to the SNF2 gene involved in transcriptional activation. It is a component of the global genome repair (GGR) complex that promotes global genome nucleotide excision repair (GG-NER) by removing DNA damage from non-transcribing DNA. RAD16 is involved in differential repair of DNA after UV damage, and repairs preferentially the MAT-alpha locus compared with the HML-alpha locus. Fission yeast rhp16, also known as ATP-dependent helicase rhp16, is a RAD16 homolog. It is involved in GGR via nucleotide excision repair (NER), in conjunction with rhp7, after UV irradiation. Both RAD16 and rhp16 contain a C3HC4-type RING-HC finger, as well as a DEAD-like helicase domain and a helicase superfamily C-terminal domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 222642141 606 CCICCDTPIDSLLYRCGHmCTCSKCANELVRS--GGK--CPLCRAPI 648
Cdd:cd16567    3 CGICHEEAEDPVVARCHH-VFCRACVKEYIESapGGKvtCPTCHKPL 48

RING finger, HC subclass, found in checkpoint with forkhead and RING finger domains protein (CHFR); CHFR, also known as RING finger protein 196 (RNF196), is a checkpoint protein that delays entry into mitosis in response to stress. It functions as an E3 ubiquitin ligase that ubiquitinates and degrades its target proteins, such as Aurora-A, Plk1, Kif22, and PARP-1, which are critical for proper mitotic transitions. It also plays an important role in cell cycle progression and tumor suppression, and is negatively regulated by SUMOylation-mediated proteasomal ubiquitylation. Moreover, CHFR is involved in the early stage of the DNA damage response, which mediates the crosstalk between ubiquitination and poly-ADP-ribosylation. CHFR contains a fork head associated (FHA) domain and a C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 222642141 605 TCCICCDtpidsLLYR------CGHMcTCSKCANE-LVRSGGKCPLCRAPIIEV 651
Cdd:cd16503    4 TCSICQD-----LLHDcvslqpCMHN-FCAACYSDwMERSNTECPTCRATVQRV 51

RING finger, HC subclass, found in RING finger protein 8 (RNF8) and similar proteins; RNF8 is a telomere-associated E3 ubiquitin-protein ligase that plays an important role in DNA double-strand break (DSB) repair via histone ubiquitination. It is localized in the nucleus and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3), but not with other E2s (UbcH5, UbcH7, UbcH10, hCdc34, and hBendless). It recruits UBC13 for lysine 63-based self polyubiquitylation. Its deficiency causes neuronal pathology and cognitive decline, and its loss results in neuron degeneration. RNF8, together with RNF168, catalyzes a series of ubiquitylation events on substrates such as H2A and H2AX, with the H2AK13/15 ubiquitylation being particularly important for recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of DSBs. RNF8 mediates the ubiquitination of gammaH2AX, and recruits 53BP1 and BRCA1 to DNA damage sites which promotes DNA damage response (DDR) and inhibits chromosomal instability. Moreover, RNF8 interacts with retinoid X receptor alpha (RXR alpha) and enhances its transcription-stimulating activity. It also regulates the rate of exit from mitosis and cytokinesis. RNF8 contains an N-terminal forkhead-associated (FHA) domain and a C-terminal C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 222642141 606 CCICCDTPIDSLLYRCGHmCTCSKCANELVRSGGKCPLCRAPI 648
Cdd:cd16535    4 CSICSELFIEAVTLNCSH-SFCSYCITEWMKRKKECPICRKPI 45

RING finger, HC subclass, found in Mus musculus tripartite motif-containing protein 43 (TRIM43) and similar propteins; This subfamily includes TRIM43A, TRIM43B and TRIM43C, which are expressed specifically in mouse preimplantation embryos. They contain a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 222642141 605 TCCICCDTPIDSLLYRCGH-MC-TCSKCANELVRSGGKCPLCRAPI 648
Cdd:cd23133    5 TCSICQGIFMNPVYLRCGHkFCeACLLLFQEDIKFPAYCPMCRQPF 50

RING finger, HC subclass, found in RING finger protein 141 (RNF141) and similar proteins; RNF141, also known as zinc finger protein 230 (ZNF230), is a RING finger protein present primarily in the nuclei of spermatogonia, the acrosome, and the tail of spermatozoa. It may have a broad function during early development of vertebrates. It plays an important role in spermatogenesis, including spermatogenic cell proliferation and sperm maturation, as well as motility and fertilization. It also exhibits DNA binding activity. RNF141/ZNF230 gene mutations may be associated with azoospermia. RNF141 contains a C3HC4-type RING finger domain that may function as an activator module in transcription.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 222642141 606 CCICCDTPIDSLLyRCGHMcTCSKCANELVRSGGKCPLCR 645
Cdd:cd16545    3 CCICMDRKADLIL-PCAHS-YCQKCIDKWSDRHRTCPICR 40

RING finger, HC subclass, found in Arabidopsis thaliana proteolysis 1 protein (PRT1) and similar proteins; PRT1, also called RING-type E3 ubiquitin transferase PRT1, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of target proteins. It functions in the N-end rule pathway of protein degradation, where it specifically recognizes and ubiquitinates proteins with an N-terminal bulky aromatic amino acid (Phe). It does not act on aliphatic hydrophobic and basic N-terminal residues (Arg or Leu) containing proteins. PRT1 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 222642141 605 TCCICCDtpidsLLYR-----CGHM----CTcSKCANELVRSggKCPLCRAP 647
Cdd:cd23132    4 LCCICLD-----LLYKpvvleCGHVfcfwCV-HRCMNGYDES--HCPLCRRP 47

RING finger, HC subclass, found in Arabidopsis thaliana SP1-like protein 2 (SPL2) and similar proteins; SPL2, also known as RING-type E3 ubiquitin transferase SPL2, acts as an E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. SPL2 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 222642141 605 TCCICCDTPIDSLLYRCGHMCTCSKCANELVRSGG-KCPLCR 645
Cdd:cd23145    5 LCVVCLLRRRRVAFIECGHRVCCELCARRVTREANpRCPVCR 46