RING finger (Really Interesting New Gene) domain and U-box domain superfamily; 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 different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are 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 enable efficient transfer of ubiquitin from E2 to the substrates.

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gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQL----SLCPLCRRHIDQVVKTF 350
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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQL----SLCPLCRRHIDQVVKTF 350
Cdd:cd16647     4 CVICYERPVDTVLYRCGHMCMCYDCALQLkrrgGSCPICRAPIKDVIKIY 53

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

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gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCC-----TSCSSQLSLCPLCRRH 342
Cdd:COG5574   218 CFLCLEEPEVPSCTPCGHLFCLsclliSWTKKKYEFCPLCRAK 260

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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQL----SLCPLCRRHIDQVVKTF 350
Cdd:cd16647     4 CVICYERPVDTVLYRCGHMCMCYDCALQLkrrgGSCPICRAPIKDVIKIY 53

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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCRRHIDQVVK 348
Cdd:cd16515     4 CVVCMDAESQVIFLPCGHVCCCQTCSSSLSTCPLCRADITQRVR 47

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 1373956165 303 SLCVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCRRHIDQVVKTF 350
Cdd:cd16500     1 DLCKICMDAAIDCVLLECGHMVTCTDCGKKLSECPICRQYVVRVVHFF 48

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 1373956165 304 LCVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCR 340
Cdd:cd16510     3 LCKICMDREVNIVFLPCGHLVTCAQCAASLRKCPICR 39

Modified RING finger, HC subclass (C3HC5-type), found in mitochondrial-anchored protein ligase (MAPL) and similar proteins; MAPL, also known as MULAN, mitochondrial ubiquitin ligase activator of NFKB 1, E3 SUMO-protein ligase MUL1, E3 ubiquitin-protein ligase MUL1, growth inhibition and death E3 ligase (GIDE), putative NF-kappa-B-activating protein 266, or RING finger protein 218 (RNF218), is a multifunctional mitochondrial outer membrane protein involved in several processes specific to metazoan (multicellular animal) cells, such as NF-kappaB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. MAPL contains a unique BAM (beside a membrane)/GIDE (growth inhibition death E3 ligase) domain and a C-terminal modified cytosolic C3HC5-type RING-HC finger which 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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSC---SSQLSLCPLCRRHIDQVV 347
Cdd:cd16648     4 CVICLSNPRSCVFLECGHVCSCIECyeaLPSPKKCPICRSFIKRVV 49

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 1373956165 304 LCVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCRRHIDQVVKTF 350
Cdd:cd16714    16 LCKICMDRNISIVFIPCGHLVTCKQCAEALDKCPICCTVITFKQKIF 62

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 1373956165 303 SLCVICLEQDYNAVLVPCGHMCCCTSCSSQLSL--CPLCR 340
Cdd:cd16649     1 GLCVVCLENPASVLLLPCRHLCLCEVCAKGLRGktCPICR 40

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 1373956165 304 LCVICLEQDYNAVLVPCGHMCCCTSCSSQL-------SLCPLCRRHIDQVV 347
Cdd:cd16788     7 KCVICQDQSKTVLILPCRHMCLCRQCANILlqqpvyrRNCPLCRTMILQTL 57

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 1373956165 303 SLCVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCRRHIDQVVKTF 350
Cdd:cd16707     3 NLCKICMDSPIDCVLLECGHMVTCTKCGKRMSECPICRQYVIRAVHVF 50

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 1373956165 303 SLCVICLEQDYNAVLVPCGHMCCCTSCSSQL----SLCPLCR 340
Cdd:cd16789     1 SECVICLSDPRDTAVLPCRHLCLCSDCAEVLryqsNKCPICR 42

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.

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gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCRRHI 343
Cdd:cd16566     5 CTLCFDKVADTELRPCGHSGFCMECALQLETCPLCRQPI 43

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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQ-----LSLCPLCRRHIDQVVK 348
Cdd:cd16722     4 CVICFENEVIAALVPCGHNLFCMECANKicekeTPSCPVCQTAVTQAIQ 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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQL-----SLCPLCRRHIDQVVKTF 350
Cdd:cd16721     7 CSICFESEVIAALVPCGHNLFCMECANRIceknePQCPVCHAAVTQAIRIF 57

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 1373956165 303 SLCVICLEQDYNAVLVpCGHMCCCtSCSSQLSLCPLCRRHI 343
Cdd:cd16520     1 ILCPICMERKKNVVFL-CGHGTCQ-KCAEKLKKCPICRKPI 39

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

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gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCC-----TSCSSQLSLCPLCRRH 342
Cdd:COG5574   218 CFLCLEEPEVPSCTPCGHLFCLsclliSWTKKKYEFCPLCRAK 260

RING finger, HC subclass, found in Arabidopsis thaliana MND1-interacting protein 1 (MIP1) and similar proteins; This subfamily includes Arabidopsis thaliana MIP1, RING finger protein 4 (RF4) and RING finger protein 298 (RF298). MIP1 interacts with MND1, HOP2 and XRI1. RF4 and RF298 are putative E3 ubiquitin-protein ligase that may mediate E2-dependent protein ubiquitination. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

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gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSL-----CPLCRRHIDQVVK 348
Cdd:cd23128     6 CVMCMEEERSVVFLPCAHQVVCSGCNDLHEKkgmreCPSCRGEIQERIR 54

second 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 second RING-HC finger.

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gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCR 340
Cdd:cd16725     3 CVVCSDKKASVLFKPCGHMCACEGCAALMKKCVQCR 38

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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSL----CPLCR 340
Cdd:cd16816    11 CVVCLSDLRDTLILPCRHLCLCNSCADTLRYqannCPICR 50

RING finger, HC subclass, found in RING finger protein unkempt-like (UNKL) and similar proteins; 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. It shows high sequence similarity with RING finger protein unkempt (UNK), which is a metazoan-specific zinc finger protein enriched in embryonic brains, and may play a broad regulatory role during the formation of the central nervous system (CNS). UNKL contains several CCCH-type zinc fingers at the N-terminus, and a C3HC4-type RING-HC finger at its C-terminus.

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                  ....*....|....*....|....*....|....*....|.
gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCRRHIDQ 345
Cdd:cd16772     3 CIVCQERDRSIVLQPCQHYVLCEHCAASKPECPYCKTKILK 43

Ring finger domain;

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                  ....*....|....*....|....*....|....*....|...
gi 1373956165 305 CVICLEQ---DYNAVLVPCGHmCCCTSCSSQL----SLCPLCR 340
Cdd:pfam13639   3 CPICLEEfeeGDKVVVLPCGH-HFHRECLDKWlrssNTCPLCR 44

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 1373956165 303 SLCVICLEQDYNAVLVpCGHmCCCTSCSSQLSLCPLCRRHIDQVVKTF 350
Cdd:cd16727     1 TMCPVCLDRLKNMIFL-CGH-GTCQLCGDRMSECPICRKAIEKRILLY 46

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 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSL----CPLCR 340
Cdd:cd16817     7 CVVCLSDVRDTLILPCRHLCLCNACADTLRYqannCPICR 46

RING finger, HC subclass, found in Equid alphaherpesvirus 1 (Equine herpesvirus 1/EHV-1) regulatory protein and similar proteins; EHV-1 regulatory protein belongs to the Vmw110 (IPC0) protein family. It contains a typical C3HC4-type RING-HC finger and binds zinc stably.

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                  ....*....|....*....|....*....|....*....|....*..
gi 1373956165 305 CVICLEQDYN-AVLVPCGHMCC--CTSCSSQLSL-CPLCRRHIDQVV 347
Cdd:cd23130     3 CPICLDDPEDeAITLPCLHQFCytCILRWLQTSPtCPLCKTPVTSII 49

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.

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1373956165 305 CVICLEQDYNAV-LVPCGHMCCcTSCSS-----QLSLCPLCRRHIDQVVK 348
Cdd:cd16503     5 CSICQDLLHDCVsLQPCMHNFC-AACYSdwmerSNTECPTCRATVQRVNK 53

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 1373956165 305 CVICLEQDYNAVLVPCGHM----CCCTSCSSQLSLCPLCR 340
Cdd:cd16509     6 CAICLDSLTNPVITPCAHVfcrrCICEVIQREKAKCPMCR 45

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.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1373956165 305 CVICLEQDYNAVLvPCGHmCCCTSCSSQLSLCPLCRRHIDQVVKTF 350
Cdd:cd16728     7 CPICIDNHIKLVF-QCGH-GSCIECSSALKACPICRQAIRERIQIF 50

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl-b and similar proteins; Cbl-b, also known as Casitas B-lineage lymphoma proto-oncogene b, RING finger protein 56 (RNF56), SH3-binding protein Cbl-b, or signal transduction protein Cbl-b, has been identified as a regulator of antigen-specific, T cell-intrinsic, peripheral immune tolerance, a state also known as clonal anergy. It may inhibit activation of the p85 subunit of phosphoinositide 3-kinase (PI3K), protein kinase C-theta (PKC-theta), and phospholipase C-gamma1 (PLC-gamma1) and negatively regulates T-cell receptor-induced transcription factor nuclear factor kappaB (NF-kappaB) activation. In addition, Cbl-b may target multiple signaling molecules involved in transforming growth factor (TGF)-beta-mediated transactivation pathways. Cbl-b contains a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, is composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain), a proline rich domain, a nuclear localization signal, a C3HC4-type RING-HC finger and an ubiquitin-associated (UBA) domain.

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1373956165 299 GGMPSLCVICLEQDYNAVLVPCGHMcCCTSC-----SSQLSLCPLCRRHI 343
Cdd:cd16709    17 GSTFQLCKICAENDKDVKIEPCGHL-MCTSCltawqESDGQGCPFCRCEI 65

RING finger, HC subclass, found in RING finger protein 146 (RNF146) and similar proteins; RNF146, also known as dactylidin, or iduna, is a cytoplasmic E3 ubiquitin-protein ligase that is responsible for PARylation-dependent ubiquitination (PARdU). It displays neuroprotective property due to its inhibition of Parthanatos, a PAR dependent cell death, via binding with Poly(ADP-ribose) (PAR). It also modulates PAR polymerase-1 (PARP-1)-mediated oxidative cell injury in cardiac myocytes. Moreover, RNF146 mediates tankyrase-dependent degradation of axin, thereby positively regulating Wnt signaling. It also facilitates DNA repair and protects against cell death induced by DNA damaging agents or gamma-irradiation by translocating to the nucleus after cellular injury and promoting the ubiquitination and degradation of various nuclear proteins involved in DNA damage repair. Furthermore, RNF146 is implicated in neurodegenerative disease and cancer development. It regulates the development and progression of non-small cell lung cancer (NSCLC) by enhancing cell growth, invasion, and survival. RNF146 contains an N-terminal C3HC4-type RING-HC finger followed by a WWE domain with a poly(ADP-ribose) (PAR) binding motif at the tail.

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gi 1373956165 305 CVICLEQDYNAVLVPCGHM-C--CCTSCSSQLSLCPLCRRHI 343
Cdd:cd16546     3 CPICLQTCIHPVKLPCGHIfCylCVKGVAWQSKRCALCRQEI 44

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)

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                   ....*....|....*....|....*....|....*....|.
gi 1373956165  305 CVICLEQ-DYNAVLVPCGHMCCCtSCSSQL-----SLCPLC 339
Cdd:smart00184   1 CPICLEEyLKDPVILPCGHTFCR-SCIRKWlesgnNTCPIC 40

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 1373956165 305 CVICLEQDYN-AVLVPCGHMCCcTSCSSQLS-------LCPLCRRHIDQV 346
Cdd:cd16554     5 CPVCLDLYYDpYMCYPCGHIFC-EPCLRQLAksspkntPCPLCRTTIRRV 53

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.

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                  ....*....|....*....|....*....|....*.
gi 1373956165 305 CVICLEQDYNAVLVPCGHMCCCTSCSSQLSLCPLCR 340
Cdd:cd16519     3 CRVCSDKKALVLFQPCGHVVACEECSLRMKKCLQCK 38

RING finger, HC subclass, found in Schizosaccharomyces pombe DNA repair protein Rad8 (SpRad8) and similar proteins; SpRad8 is a conserved protein homologous to Saccharomyces cerevisiae DNA repair protein Rad5 and human helicase-like transcription factor (HLTF) that is required for error-free postreplication repair by contributing to polyubiquitylation of PCNA. SpRad8 contains a C3HC4-type RING-HC finger responsible for the E3 ubiquitin ligase activity, a SNF2-family helicase domain including an ATP binding site, and a family-specific HIRAN domain (HIP116, Rad5p N-terminal domain) that contributes to nuclear localization.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1373956165 305 CVICLEQDY-NAVLVPCGHMCC--CTS-----CSS--QLSLCPLCRRHIDQ 345
Cdd:cd16572     7 CPICAEEPIsELALTRCWHSACkdCLLdhiefQKSknEVPLCPTCRQPINE 57

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.

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                  ....*....|....*....|....*....|....*....|...
gi 1373956165 305 CVICLEQDYNAVLVPCGHmCCCTSCSSQL-----SLCPLCRRH 342
Cdd:cd16596    12 CPICLDPFVEPVSIECGH-SFCQECISQVgkgggSVCPVCRQR 53

Variant RING finger, HC subclass (C4C4-type), found in retinoblastoma-binding protein 6 (RBBP6) and similar proteins; RBBP6, also known as proliferation potential-related protein, protein P2P-R, retinoblastoma-binding Q protein 1 (RBQ-1), or p53-associated cellular protein of testis (PACT), is a nuclear E3 ubiquitin-protein ligase involved in multiple processes, such as the control of gene expression, mitosis, cell differentiation, and cell apoptosis. It plays a role in both promoting and inhibiting apoptosis in many human cancers, including esophageal, lung, hepatocellular, and colon cancers, familial myeloproliferative neoplasms, as well as in human immunodeficiency virus-associated nephropathy (HIVAN). It functions as an Rb- and p53-binding protein that plays an important role in chaperone-mediated ubiquitination and possibly in protein quality control. It acts as a scaffold protein to promote the assembly of the p53/TP53-MDM2 complex, resulting in an increase of MDM2-mediated ubiquitination and degradation of p53/TP53, and leading to both apoptosis and cell growth. It is also a double-stranded RNA-binding protein that plays a role in mRNA processing by regulating the human polyadenylation machinery and modulating expression of mRNAs with AU-rich 3' untranslated regions (UTRs). Moreover, RBBP6 ubiquitinates and destabilizes the transcriptional repressor ZBTB38 that negatively regulates transcription and levels of the MCM10 replication factor on chromatin. Furthermore, RBBP6 is involved in tunicamycin-induced apoptosis by mediating protein kinase (PKR) activation. RBBP6 contains an N-terminal ubiquitin-like domain and a C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger. RBBP6 interacts with chaperones Hsp70 and Hsp40 through its N-terminal ubiquitin-like domain. It promotes the ubiquitination of p53 by Hdm2 in an E4-like manner through its RING finger. It also interacts directly with the pro-proliferative transcription factor Y-box-binding protein-1 (YB-1) via its RING finger.

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gi 1373956165 304 LCVICLEQDYNAVLVPCGHMCCCTSCSSQL-----SLCPLCRRHIDQV 346
Cdd:cd16620     5 KCPICKDLMKDAVLTPCCGNSFCDECIRTAlleedFTCPTCKEPDVSP 52

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM41, TRIM52 and similar proteins; TRIM41 and TRIM52, two closely related tripartite motif-containing proteins, have dramatically expanded RING domains compared with the rest of the TRIM family proteins. TRIM41 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. In contrast, TRIM52 lacks the putative viral recognition SPRY/B30.2 domain, and thus has been classified to the C-V subclass of the TRIM family that contains only RBCC domains. TRIM41, also known as RING finger-interacting protein with C kinase (RINCK), is an E3 ubiquitin-protein ligase that promotes the ubiquitination of protein kinase C (PKC) isozymes in cells. It specifically recognizes the C1 domain of PKC isozymes. It controls the amplitude of PKC signaling by controlling the amount of PKC in the cell. TRIM52, also known as RING finger protein 102 (RNF102), is encoded by a novel, noncanonical antiviral TRIM52 gene in primate genomes with unique specificity determined by the rapidly evolving RING domain.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1373956165 303 SLCVICLEQDYNAVLVPCGHMcCCTSCSSQL--SLCPLCRRHIDQvvKTFR 351
Cdd:cd16602     4 AVCAICLDYFKDPVSIGCGHN-FCRVCVTQLwgFTCPQCRKSFPR--RSFR 51