RING finger, HC subclass, found in peroxin-2 (PEX2) and similar proteins; PEX2, also known as peroxisome biogenesis factor 2, 35 kDa peroxisomal membrane protein, peroxisomal membrane protein 3, peroxisome assembly factor 1 (PAF-1), or RING finger protein 72 (RNF72), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It may be involved in the biogenesis of peroxisomes, as well as in peroxisomal matrix protein import. Mutations in the PEX2 gene are the primary defect in a subset of patients with Zellweger syndrome and related peroxisome biogenesis disorders. Moreover, PEX2 functions as an E3-ubiquitin ligase that mediates the UBC4-dependent polyubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1935598096 242 KECALCGEWPT-MPHTIGCEHVFCYYCVKSSFLFDMYFTCPKCGTEVH 288
Cdd:cd16526     2 TECAICGEWPTnNPYSTGCGHVYCYYCIKSNLLADDSFTCPRCGSPVS 49

RING finger, HC subclass, found in peroxin-2 (PEX2) and similar proteins; PEX2, also known as peroxisome biogenesis factor 2, 35 kDa peroxisomal membrane protein, peroxisomal membrane protein 3, peroxisome assembly factor 1 (PAF-1), or RING finger protein 72 (RNF72), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It may be involved in the biogenesis of peroxisomes, as well as in peroxisomal matrix protein import. Mutations in the PEX2 gene are the primary defect in a subset of patients with Zellweger syndrome and related peroxisome biogenesis disorders. Moreover, PEX2 functions as an E3-ubiquitin ligase that mediates the UBC4-dependent polyubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 1935598096 242 KECALCGEWPT-MPHTIGCEHVFCYYCVKSSFLFDMYFTCPKCGTEVH 288
Cdd:cd16526     2 TECAICGEWPTnNPYSTGCGHVYCYYCIKSNLLADDSFTCPRCGSPVS 49

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 1935598096  244 CALC-GEWPTMPHTIGCEHVFCYYCVKSSFLfDMYFTCPKC 283
Cdd:smart00184   1 CPIClEEYLKDPVILPCGHTFCRSCIRKWLE-SGNNTCPIC 40

RING finger, HC subclass, found in peroxin-2 (PEX2) and similar proteins; PEX2, also known as peroxisome biogenesis factor 2, 35 kDa peroxisomal membrane protein, peroxisomal membrane protein 3, peroxisome assembly factor 1 (PAF-1), or RING finger protein 72 (RNF72), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It may be involved in the biogenesis of peroxisomes, as well as in peroxisomal matrix protein import. Mutations in the PEX2 gene are the primary defect in a subset of patients with Zellweger syndrome and related peroxisome biogenesis disorders. Moreover, PEX2 functions as an E3-ubiquitin ligase that mediates the UBC4-dependent polyubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 1935598096 242 KECALCGEWPT-MPHTIGCEHVFCYYCVKSSFLFDMYFTCPKCGTEVH 288
Cdd:cd16526     2 TECAICGEWPTnNPYSTGCGHVYCYYCIKSNLLADDSFTCPRCGSPVS 49

RING finger found in polycomb group RING finger protein 5 (PCGF5) and similar proteins; PCGF5, also known as RING finger protein 159 (RNF159), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR) and serves as the core component of a Polycomb repressive complex 1 (PRC1). Like other PCGF homologs, PCGF5 associates with ring finger protein 2 (RNF2) to form a RNF2-PCGF heterodimer, which is catalytically competent as an E3 ubiquitin transferase and is the scaffold for the assembly of additional components. PCGF5 contains a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*....|...
gi 1935598096 244 CALCGEWPTMPHTIG-CEHVFCYYCVKSSFLFDMYftCPKCGTEVHSVQPLKS 295
Cdd:cd16737    13 CRICKGYLIKPTTVTeCLHTFCKSCIVQHFEDSND--CPECGIQVHETNPLEM 63

RING finger, HC subclass, found in RING finger protein 125 (RNF125); RNF125, also known as T-cell RING activation protein 1 (TRAC-1), is an E3 ubiquitin-protein ligase that is predominantly expressed in lymphoid cells, and functions as a positive regulator of T cell activation. It also down-modulates HIV replication and inhibits pathogen-induced cytokine production. It negatively regulates type I interferon signaling, which conjugates Lys(48)-linked ubiquitination to retinoic acid-inducible gene-I (RIG-I) and subsequently leads to the proteasome-dependent degradation of RIG-I. Further, RNF125 conjugates ubiquitin to melanoma differentiation-associated gene 5 (MDA5), a family protein of RIG-I. It thus acts as a negative regulator of RIG-I signaling, and is a direct target of miR-15b in the context of Japanese encephalitis virus (JEV) infection. Moreover, RNF125 binds to and ubiquitinates JAK1, prompting its degradation and inhibition of receptor tyrosine kinase (RTK) expression. It also negatively regulates p53 function through physical interaction and ubiquitin-mediated proteasome degradation. Mutations in RNF125 may lead to overgrowth syndromes (OGS). RNF125, together with three closely related proteins: RNF114, RNF138 and RNF166, forms a novel family of ubiquitin ligases with a C3HC4-type RING-HC finger, a C2HC-, and two C2H2-type zinc fingers, as well as a ubiquitin interacting motif (UIM). The UIM of RNF125 binds K48-linked poly-ubiquitin chains and is, together with the RING domain, required for auto-ubiquitination.

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                  ....*....|....*....|....*....|....*....|....*..
gi 1935598096 243 ECALCGEWPTMPHTIGCEHVFCYYCVKSSFLFDMYfTCPKCGTEVHS 289
Cdd:cd16542     3 DCAVCLEVLHQPVRTRCGHVFCRPCIATSLRNNTW-TCPYCRAYLSS 48

RING finger found in polycomb group RING finger protein 2 (PCGF2) and similar proteins; PCGF2, also known as DNA-binding protein Mel-18, RING finger protein 110 (RNF110), or zinc finger protein 144 (ZNF144), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR). It serves as the core component of a canonical Polycomb repressive complex 1 (PRC1), which is composed of a chromodomain-containing protein (CBX2, CBX4, CBX6, CBX7 or CBX8) and a Polyhomeotic protein (PHC1, PHC2, or PHC3). Like other PCGF homologs, PCGF2 associates with ring finger protein 2 (RNF2) to form a RNF2-PCGF heterodimer, which is catalytically competent as an E3 ubiquitin transferase and is the scaffold for the assembly of additional components. Moreover, PCGF2 uniquely regulates PRC1 to specify mesoderm cell fate in embryonic stem cells. It is required for PRC1 stability and maintenance of gene repression in embryonic stem cells (ESCs) and essential for ESC differentiation into early cardiac-mesoderm precursors. PCGF2 also plays a significant role in the angiogenic function of endothelial cells (ECs) by regulating endothelial gene expression. Furthermore, PCGF2 is a SUMO-dependent regulator of hormone receptors. It facilitates the deSUMOylation process by inhibiting PCGF4/BMI1-mediated ubiquitin-proteasomal degradation of SUMO1/sentrin-specific protease 1 (SENP1). It is also a novel negative regulator of breast cancer stem cells (CSCs) that inhibits the stem cell population and in vitro and in vivo self-renewal through the inactivation of Wnt-mediated Notch signaling. PCGF2 contains a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*....|...
gi 1935598096 244 CALCGEWPTMPHTI-GCEHVFCYYCVKSSFLFDMYftCPKCGTEVHSVQPLKS 295
Cdd:cd16734    17 CALCGGYFIDAATIvECLHSFCKTCIVRYLETNKY--CPMCDVQVHKTRPLLS 67

RING finger found in polycomb group RING finger protein 6 (PCGF6) and similar proteins; PCGF6, also known as Mel18 and Bmi1-like RING finger (MBLR), or RING finger protein 134 (RNF134), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR). It serves as the core component of a noncanonical Polycomb repressive complex 1 (PRC1)-like L3MBTL2 complex, which is composed of some canonical components, such as RNF2, CBX3, CXB4, CXB6, CXB7, and CXB8, as well as some noncanonical components, such as L3MBTL2, E2F6, WDR5, HDAC1, and RYBP, and plays a critical role in epigenetic transcriptional silencing in higher eukaryotes. Like other PCGF homologs, PCGF6 possesses the transcriptional repression activity, and also associates with ring finger protein 2 (RNF2) to form a RNF2-PCGF heterodimer, which is catalytically competent as an E3 ubiquitin transferase and is the scaffold for the assembly of additional components. Moreover, PCGF6 can regulate the enzymatic activity of JARID1d/KDM5D, a trimethyl H3K4 demethylase, through direct interaction. Furthermore, PCGF6 is expressed predominantly in meiotic and post-meiotic male germ cells and may play important roles in mammalian male germ cell development. It also regulates mesodermal lineage differentiation in mammalian embryonic stem cells (ESCs) and functions in induced pluripotent stem (iPS) reprogramming. The activity of PCGF6 is found to be regulated by cell cycle dependent phosphorylation. PCGF6 contains a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1935598096 244 CALCGEWPTMPHTIG-CEHVFCYYCVKSSFLFDMyfTCPKCGTEVHSVQPL 293
Cdd:cd16738    10 CSICKGYFIDATTITeCLHTFCKSCIVRHFYYSN--RCPKCNIVVHQTQPL 58

RING finger, HC subclass, found in tripartite motif-containing protein 39 (TRIM39) and similar proteins; TRIM39, also known as RING finger protein 23 (RNF23) or testis-abundant finger protein, is an E3 ubiquitin-protein ligase that plays a role in controlling DNA damage-induced apoptosis through inhibition of the anaphase promoting complex (APC/C), a multiprotein ubiquitin ligase that controls multiple cell cycle regulators, including cyclins, geminin, and others. TRIM39 also functions as a regulator of several key processes in the proliferative cycle. It directly regulates p53 stability. It modulates cell cycle progression and DNA damage responses via stabilizing p21. Moreover, TRIM39 negatively regulates the nuclear factor kappaB (NFkappaB)-mediated signaling pathway through stabilization of Cactin, an inhibitor of NFkappaB- and Toll-like receptor (TLR)-mediated transcription, which is induced by inflammatory stimulants such as tumor necrosis factor alpha. Furthermore, TRIM39 is a MOAP-1-binding protein that can promote apoptosis signaling through stabilization of MOAP-1 via the inhibition of its poly-ubiquitination process. TRIM39 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 1935598096 244 CALCGEWPTMPHTIGCEHVFCYYCVKSSFL-FDMYFTCPKC 283
Cdd:cd16601     4 CSLCKEYLKDPVIIECGHNFCRACITRFWEeLDGDFPCPQC 44

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Hakai, zinc finger protein 645 (ZNF645), and similar proteins; Hakai, also known as Casitas B-lineage lymphoma-transforming sequence-like protein 1, RING finger protein 188 (RNF188), or c-Cbl-like protein 1 (CBLL1), is an E3 ubiquitin ligase that disrupts cell-cell contacts in epithelial cells and is upregulated in human colon and gastric adenocarcinomas. It was identified to mediate the posttranslational downregulation of E-cadherin (CDH1), a major component of adherens junctions in epithelial cells and a potent tumor suppressor. It also promotes ubiquitination of several other tyrosine-phosphorylated Src substrates, including cortactin (CTTN) and DOK1. Hakai acts as a homodimer arranged in an anti-parallel configuration with a novel HYB (Hakai pTyr-binding) domain that forms a phosphotyrosine-binding pocket. Each monomer contains a C3HC4-type RING-HC finger and a short pTyr-B domain that incorporates a novel, atypical C2H2-type Zn-finger coordination motif. Both domains are important for dimerization. ZNF645 is a novel testis-specific E3 ubiquitin-protein ligase that plays a role in sperm production and quality control. It has a structure similar to that of the c-Cbl-like protein Hakai. In contrast to Hakai, its HYB domain demonstrates different target specificities. It interacts with v-Src-phosphorylated E-cadherin, but not to cortactin.

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                  ....*....|....*....|....*....|....*....|
gi 1935598096 257 IGCEHVFCYYCVKSSflfdmYFTCPKCGTEVHSVQPLKSG 296
Cdd:cd16508    17 IPCKHVFCLDCARLH-----DKICPRCDDPVQRIEQCTRG 51

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 1 (RNFT1); RNFT1, also known as protein PTD016, is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

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gi 1935598096 230 TAGSDSTLGSSGKECALCGEWPTMPHTIGCEHVFCYYCVksSFLFDMYFTCPKCGT 285
Cdd:cd16741     3 IAASKRQCSEADDICAICQAEFRKPILLICQHVFCEECI--SLWFNREKTCPLCRT 56

RING finger, HC subclass, found in Arabidopsis thaliana protein CHROMATIN REMODELING 27 (CHR27) and similar proteins; CHR27, also called protein SNF2-RING-HELICASE-LIKE 1, is a probable helicase-like transcription factor involved in transcriptional gene silencing. It associates with SUVR2 and contributes to transcriptional gene silencing at RNA-directed DNA methylation (RdDM) target loci but also at RdDM-independent target loci. It may be involved in nucleosome positioning to form ordered nucleosome arrays on chromatin. It associates with SUVR2 and functions redundantly with FRG2. It is required for the efficient methylation of a broad range of RdDM target loci. CHR27 contains a typical C3HC4-type RING-HC finger.

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gi 1935598096 244 CALCGEWPTMPHTIGCEHVFCYYCV----KSSFLFDMYFTCPKCGTEV 287
Cdd:cd23142     3 CPICNDPPEDAVVTLCGHVFCCECVfqylSSDRTCRQFNHCPLCRQKL 50

RING finger found in polycomb group RING finger protein 4 (PCGF4) and similar proteins; PCGF4, also known as polycomb complex protein BMI-1 (B cell-specific Moloney murine leukemia virus integration site 1) or RING finger protein 51 (RNF51), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR). It serves as the core component of a canonical Polycomb repressive complex 1 (PRC1), which is composed of a chromodomain-containing protein (CBX2, CBX4, CBX6, CBX7 or CBX8) and a Polyhomeotic protein (PHC1, PHC2, or PHC3), and plays important roles in chromatin compaction and H2AK119 monoubiquitination. PCGF4 associates with the Runx1/CBFbeta transcription factor complex to silence target genes in a PRC2-independent manner. Moreover, PCGF4 is expressed in the hair cells and supporting cells. It can regulate cell survival by controlling mitochondrial function and reactive oxygen species (ROS) level in thymocytes and neurons, thus having an important role in the survival and sensitivity to ototoxic drug of auditory hair cells. Furthermore, PCGF4 controls memory CD4 T-cell survival through direct repression of Noxa gene in an Ink4a- and Arf-independent manner. It is required in neurons to suppress p53-induced apoptosis via regulating the antioxidant defensive response, and also involved in the tumorigenesis of various cancer types. PCGF4 contains a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1935598096 244 CALCGEWPTMPHTI-GCEHVFCYYCVKSSFLFDMYftCPKCGTEVHSVQPL 293
Cdd:cd16736    14 CVLCGGYFIDATTIiECLHSFCKTCIVRYLETSKY--CPICDVQVHKTRPL 62

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein RNFT1, RNFT2, and similar proteins; Both RNFT1 and RNFT2 are multi-pass membrane proteins containing a C3HC4-type RING-HC finger. Their biological roles remain unclear.

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                  ....*....|....*....|....*....|....*....|
gi 1935598096 244 CALCGEWPTMPHTIGCEHVFCYYCVksSFLFDMYFTCPKC 283
Cdd:cd16532     3 CPICQDEFKDPVVLRCKHIFCEDCV--SEWFERERTCPLC 40