RING finger, HC subclass, found in RING finger protein 220 (RNF220) and similar proteins; RNF220 is an E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of Sin3B, a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. It can also bind E2 and mediate auto-ubiquitination of itself. Moreover, RNF220 specifically interacts with beta-catenin, and enhances canonical Wnt signaling through ubiquitin-specific protease 7 (USP7)-mediated deubiquitination and stabilization of beta-catenin, which is independent of its E3 ligase activity. RNF220 contains a characteristic C3HC4-type RING-HC finger at its C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 985801720 299 YKCLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCNTITAPGDLRR 350
Cdd:cd16563    1 YKCLICMDSYTMPLVSIQCWHVHCEECWLRTLGAKKLCPQCNTITSPADLRR 52

RING finger, HC subclass, found in RING finger protein 220 (RNF220) and similar proteins; RNF220 is an E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of Sin3B, a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. It can also bind E2 and mediate auto-ubiquitination of itself. Moreover, RNF220 specifically interacts with beta-catenin, and enhances canonical Wnt signaling through ubiquitin-specific protease 7 (USP7)-mediated deubiquitination and stabilization of beta-catenin, which is independent of its E3 ligase activity. RNF220 contains a characteristic C3HC4-type RING-HC finger at its C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 985801720 299 YKCLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCNTITAPGDLRR 350
Cdd:cd16563    1 YKCLICMDSYTMPLVSIQCWHVHCEECWLRTLGAKKLCPQCNTITSPADLRR 52

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|..
gi 985801720   301 CLICMDSYSMPLTSIQCWHVHCEEC---WLRTLGAKklCPQC 339
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCirkWLESGNNT--CPIC 40

RING finger, HC subclass, found in RING finger protein 220 (RNF220) and similar proteins; RNF220 is an E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of Sin3B, a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. It can also bind E2 and mediate auto-ubiquitination of itself. Moreover, RNF220 specifically interacts with beta-catenin, and enhances canonical Wnt signaling through ubiquitin-specific protease 7 (USP7)-mediated deubiquitination and stabilization of beta-catenin, which is independent of its E3 ligase activity. RNF220 contains a characteristic C3HC4-type RING-HC finger at its C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 985801720 299 YKCLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCNTITAPGDLRR 350
Cdd:cd16563    1 YKCLICMDSYTMPLVSIQCWHVHCEECWLRTLGAKKLCPQCNTITSPADLRR 52

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 985801720 300 KCLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCNTI 342
Cdd:cd16506    2 TCPICLDEIQNKKTLEKCKHSFCEDCIDRALQVKPVCPVCGVV 44

Modified RING finger, C3HGC3-type, found in RING finger and WD repeat domain-containing protein 3 (RFWD3) and similar proteins; RFWD3, also known as RING finger protein 201 (RNF201) or FLJ10520, is an E3 ubiquitin-protein ligase that forms a complex with Mdm2 and p53 to synergistically ubiquitinate p53 and acts as a positive regulator of p53 stability in response to DNA damage. It is phosphorylated by checkpoint kinase ATM/ATR and the phosphorylation mutant fails to stimulate p53 ubiquitination. RFWD3 also functions as a novel replication protein A (RPA)-associated protein involved in DNA replication checkpoint control. RFWD3 contains an N-terminal SQ-rich region followed by a RING finger domain that exhibits robust E3 ubiquitin ligase activity toward p53, a coiled-coil domain and three WD40 repeats in the C-terminus, the latter two of which may be responsible for protein-protein interaction. The RING finger in this family is a modified C3HGC3-type RING finger, but not a canonical C3H2C3-type RING-H2 finger or C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 985801720 301 CLICMDSYSMP----LTSIQCWHVHCEEC---WLRTLGAKklCPQCNTITAPGDLRRIY 352
Cdd:cd16450    5 CPICFEPWTSSgehrLVSLKCGHLFGYSCiekWLKGKGKK--CPQCNKKAKRSDIRPLY 61

RING finger, HC subclass, found in postreplication repair protein RAD18 and similar proteins; RAD18, also known as HR18 or RING finger protein 73 (RNF73), is an E3 ubiquitin-protein ligase involved in post replication repair of UV-damaged DNA via its recruitment to stalled replication forks. It associates to the E2 ubiquitin conjugating enzyme UBE2B to form the UBE2B-RAD18 ubiquitin ligase complex involved in mono-ubiquitination of DNA-associated PCNA on K164. It also interacts with another E2 ubiquitin conjugating enzyme RAD6 to form a complex that monoubiquitinates proliferating cell nuclear antigen at stalled replication forks in DNA translesion synthesis. Moreover, Rad18 is a key factor in double-strand break DNA damage response (DDR) pathways via its association with K63-linked polyubiquitylated chromatin proteins. It can function as a mediator for DNA damage response signals to activate the G2/M checkpoint in order to maintain genome integrity and cell survival after ionizing radiation (IR) exposure. RAD18 contains a C3HC4-type RING-HC finger, a ubiquitin-binding zinc finger domain (UBZ), a SAP (SAF-A/B, Acinus and PIAS) domain, and a RAD6-binding domain (R6BD).

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 985801720 297 DRYKCLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCNTITAPGDL 348
Cdd:cd16529    3 DLLRCPICFEYFNTAMMITQCSHNYCSLCIRRFLSYKTQCPTCRAAVTESDL 54

RING finger, HC subclass, found in polycomb group RING finger protein 1 (PCGF1) and similar proteins; PCGF1, also known as nervous system Polycomb-1 (NSPc1) or RING finger protein 68 (RNF68), 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 BCOR complex that also contains RING1, RNF2, RYBP, SKP1, as well as the BCL6 co-repressor BCOR and the histone demethylase KDM2B, and is required to maintain the transcriptionally repressive state of some genes, such as Hox genes, BCL6 and the cyclin-dependent kinase inhibitor, CDKN1A. PCGF1 promotes cell cycle progression and enhances cell proliferation as well. It is a cell growth regulator that acts as a transcriptional repressor of p21Waf1/Cip1 via the retinoid acid response element (RARE element). Moreover, PCGF1 functions as an epigenetic regulator involved in hematopoietic cell differentiation. It cooperates with the transcription factor runt-related transcription factor 1 (Runx1) in regulating differentiation and self-renewal of hematopoietic cells. Furthermore, PCGF1 represents a physical and functional link between Polycomb function and pluripotency. PCGF1 contains a C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 985801720 285 RVRELERQLSrgdrykCLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCN 340
Cdd:cd16733    2 KIKDLNEHIV------CYLCAGYFIDATTITECLHTFCKSCIVKYLQTSKYCPMCN 51

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3) and similar proteins; DTX3, also known as RING finger protein 154 (RNF154), is an E3 ubiquitin-protein ligase that belongs to the Deltex (DTX) family. In contrast to other DTXs, DTX3 does not contain two N-terminal Notch-binding WWE domains, but a short unique N-terminal domain, suggesting it does not interact with the intracellular domain of Notch. Its C-terminal region includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain.

                         10        20        30
                 ....*....|....*....|....*....|....*....
gi 985801720 301 CLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQC 339
Cdd:cd16711    4 CPICLGEIQNKKTLDKCKHSFCEDCITRALQVKKACPMC 42

RING finger, HC subclass, found in yeast Bre1 and its homologs from eukaryotes; Bre1 is an E3 ubiquitin-protein ligase that catalyzes monoubiquitination of histone H2B in concert with the E2 ubiquitin-conjugating enzyme, Rad6. The Rad6-Bre1-mediated histone H2B ubiquitylation modulates the formation of double-strand breaks (DSBs) during meiosis in yeast. it is also required, indirectly, for the methylation of histone 3 on lysine 4 (H3K4) and 79. RNF20, also known as BRE1A and RNF40, also known as BRE1B, are the mammalian homologs of Bre1. They work together to form a heterodimeric Bre1 complex that facilitate the K120 monoubiquitination of histone H2B (H2Bub1), a DNA damage-induced histone modification that is crucial for recruitment of the chromatin remodeler SNF2h to DNA double-strand break (DSB) damage sites. Moreover, the Bre1 complex acts as a tumor suppressor, augmenting expression of select tumor suppressor genes and suppressing select oncogenes. Deficiency in the mammalian histone H2B ubiquitin ligase Bre1 leads to replication stress and chromosomal instability. All subfamily members contain a C3HC4-type RING-HC finger at its C-terminus.

                         10        20        30
                 ....*....|....*....|....*....|....*.
gi 985801720 317 CWHVHCEECWLRTLGAK-KLCPQCNTITAPGDLRRI 351
Cdd:cd16499   24 CGHVFCNECVQKRLETRqRKCPGCGKAFGANDVQRI 59

RING finger, HC subclass, found in human homolog of Drosophila ariadne (HHARI) and similar proteins; This subfamily includes Drosophila melanogaster protein ariadne-1 (ARI-1), and its eukaryotic homologs, such as HHARI. ARI-1 is a widely expressed Drosophila RING-finger protein that localizes mainly in the cytoplasm and is required for neural development. It interacts with a novel ubiquitin-conjugating enzyme, UbcD10. HHARI, also known as H7-AP2, monocyte protein 6 (MOP-6), protein ariadne-1 homolog, Ariadne RBR E3 ubiquitin protein ligase 1 (ARIH1), ariadne-1 (ARI-1), UbcH7-binding protein, UbcM4-interacting protein, or ubiquitin-conjugating enzyme E2-binding protein 1, is an RBR-type E3 ubiquitin-protein ligase highly expressed in nuclei, where it is co-localized with nuclear bodies including Cajal, PML, and Lewy bodies. It interacts with the E2 conjugating enzymes UbcH7, UbcH8, UbcM4, and UbcD10 in human, mouse, and fly, and modulates the ubiquitylation of substrate proteins including single-minded 2 (SIM2) and translation initiation factor 4E homologous protein (4EHP). It functions as a potent mediator of DNA damage-induced translation arrest, which protects stem and cancer cells against genotoxic stress by initiating a 4EHP-mediated mRNA translation arrest. HHARI contains an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 985801720 301 CLICMDSYSMP-LTSIQCWHVHCEECWLRTLGAKKLC-PQCNTITAP 345
Cdd:cd16626    3 CDICYLNYPNSyMTGLECGHKFCMQCWKEYLTTKIMEeGMGQTISCP 49

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 985801720 290 ERQLSRGDRYkCLICMDSYSMPLTSIqCWHVHCEECWLRTLGAKKLCPQCNTI 342
Cdd:cd16741    7 KRQCSEADDI-CAICQAEFRKPILLI-CQHVFCEECISLWFNREKTCPLCRTV 57

RING finger, HC subclass, found in really interesting new gene proteins RING1, RING2 and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), is a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. Both RING1 and RING2 are core components of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING2 acts as the main E3 ubiquitin ligase on histone H2A of the PRC1 complex, while RING1 may rather act as a modulator of RNF2/RING2 activity. Members of this family contain a C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 985801720 301 CLICMDSYSMPLTSIQCWHVHCEEC---WLRTLgaKKLCPQC 339
Cdd:cd16531    4 CPICLGIIKNTMTVKECLHRFCAECiekALRLG--NKECPTC 43

RING finger, HC subclass, found in RING finger protein 4 (RNF4) and similar proteins; RNF4, also known as small nuclear ring finger protein (SNURF), is a SUMO-targeted E3 ubiquitin-protein ligase with a pivotal function in the DNA damage response (DDR) by interacting with the deubiquitinating enzyme ubiquitin-specific protease 11 (USP11), a known DDR-component, and further facilitating DNA repair. It plays a novel role in preventing the loss of intact chromosomes and ensures the maintenance of chromosome integrity. Moreover, RNF4 is responsible for the UbcH5A-catalyzed formation of K48 chains that target SUMO-modified promyelocytic leukemia (PML) protein for proteasomal degradation in response to arsenic treatment. It also interacts with telomeric repeat binding factor 2 (TRF2) in a small ubiquitin-like modifier (SUMO)-dependent manner and preferentially targets SUMO-conjugated TRF2 for ubiquitination through SUMO-interacting motifs (SIMs). Furthermore, RNF4 can form a complex with a Ubc13-ubiquitin conjugate and Ube2V2. It catalyzes K63-linked polyubiquitination by the Ube2V2-Ubc13 (ubiquitin-loaded) complex. Meanwhile, RNF4 negatively regulates nuclear factor kappa B (NF-kappaB) signaling by down-regulating transforming growth factor beta (TGF-beta)-activated kinase 1 (TAK1)-TAK1-binding protein2 (TAB2). RNF4 contains four SIMs followed by a C3HC4-type RING-HC finger at the C-terminus.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 985801720 301 CLICMDSYS------MPLTSIQCWHVHCEECWLRTLGAKKLCPQC 339
Cdd:cd16533    6 CPICMDGYSeivqsgRLIVSTECGHVFCSQCLRDSLKNANTCPTC 50

RING finger, HC subclass, found in Saccharomyces cerevisiae increased recombination centers protein 20 (IRC20) and similar proteins; IRC20 is an uncharacterized ATP-dependent helicase that is probably involved in a pathway contributing to genomic integrity. IRC20 contains a typical C3HC4-type RING-HC finger.

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                 ....*....|....*....|....*....|....*....|....
gi 985801720 296 GDRYKCLICMDSYSMPlTSIQCWHVHCEECWLRTLGAKKLCPQC 339
Cdd:cd23135    1 KQKLSCSICFSEIRSG-AILKCGHFFCLSCIASWLREKSTCPLC 43

RING finger, HC subclass, found in tripartite motif-containing protein 77 (TRIM77) and similar proteins; TRIM77 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 two consecutive zinc-binding domains, a C3HC4-type RING-HC finger and Bbox2, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain.

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                 ....*....|....*....|....*....|....*....|....*....|...
gi 985801720 297 DRYKCLICMDSYSMPLTsIQCWHVHCEEC----WLRTLGAKKlCPQCNTITAP 345
Cdd:cd16543    2 DQLTCSICLDLLKDPVT-IPCGHSFCMNCitllWDRKQGVPS-CPQCRESFPP 52

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 985801720 301 CLICMDSYSMPLTSIQCWHVHCEECWLRTLGAKKLCPQCNT 341
Cdd:cd16736   14 CVLCGGYFIDATTIIECLHSFCKTCIVRYLETSKYCPICDV 54