RING finger, H2 subclass, found in the PA-TM-RING ubiquitin ligase family; The PA-TM-RING family represents a group of transmembrane-type E3 ubiquitin ligases, which has been characterized by an N-terminal transient signal peptide, a PA (protease-associated) domain, a TM (transmembrane) domain, as well as a C-terminal C3H2C3-type RING-H2 finger domain. It includes RNF13, RNF167, ZNRF4 (zinc and RING finger 4), GRAIL (gene related to anergy in lymphocytes)/RNF128, RNF130, RNF133, RNF148, RNF149 and RNF150 (which are more closely related), as well as RNF43 and ZNRF3, which have substantially longer C-terminal tail extensions compared with the others. PA-TM-RING proteins are expressed at low levels in all mammalian tissues and species, but they are not present in yeast. They play a common regulatory role in intracellular trafficking/sorting, suggesting that abrogation of their function may result in dysregulation of cellular signaling events in cancer.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQnSSTCPMCK 343
Cdd:cd16454     2 CAICLEEFKEGEKVRVLPCNHLFHKDCIDPWLEQ-HNTCPLCR 43

RING finger, H2 subclass, found in the PA-TM-RING ubiquitin ligase family; The PA-TM-RING family represents a group of transmembrane-type E3 ubiquitin ligases, which has been characterized by an N-terminal transient signal peptide, a PA (protease-associated) domain, a TM (transmembrane) domain, as well as a C-terminal C3H2C3-type RING-H2 finger domain. It includes RNF13, RNF167, ZNRF4 (zinc and RING finger 4), GRAIL (gene related to anergy in lymphocytes)/RNF128, RNF130, RNF133, RNF148, RNF149 and RNF150 (which are more closely related), as well as RNF43 and ZNRF3, which have substantially longer C-terminal tail extensions compared with the others. PA-TM-RING proteins are expressed at low levels in all mammalian tissues and species, but they are not present in yeast. They play a common regulatory role in intracellular trafficking/sorting, suggesting that abrogation of their function may result in dysregulation of cellular signaling events in cancer.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQnSSTCPMCK 343
Cdd:cd16454     2 CAICLEEFKEGEKVRVLPCNHLFHKDCIDPWLEQ-HNTCPLCR 43

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1488160602 195 VIEVTLIVIIVLLGISFVASVAMHCHLYRRRRNMqlnqDGNVDPESGRPRASTLNTATLDQLPIK----VFKKSSKDD-- 268
Cdd:COG5540   204 EDPVTLTTSINVTWDGLGNTYQAPSQSAEAQDET----GDMFWPRLSRFVGSRGFRVVFPRIPSQelrfLFLTQSKGSrf 279

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1488160602 269 IQMKKIETN-DEENKISDEEHEKSDFTEELNDL-------------CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQ 334
Cdd:COG5540   280 NIILEIQINfDVGFYSSSEAIPTTTTKGSLKPLsieraveadkgveCAICMSNFIKNDRLRVLPCDHRFHVGCVDKWLLG 359

                         170       180
                  ....*....|....*....|....*.
gi 1488160602 335 NSSTCPMCKgdvlevvpkceTPLPAP 360
Cdd:COG5540   360 YSNKCPVCR-----------TAIPPP 374

HRD ubiquitin ligase complex, ER membrane component [Posttranslational modification, protein turnover, chaperones];

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDE-FDPGDEL---------RELPCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:COG5243   290 CTICMDEmFHPDHEPlprgldmtpKRLPCGHILHLHCLKNWL-ERQQTCPICR 341

RING finger, H2 subclass, found in the PA-TM-RING ubiquitin ligase family; The PA-TM-RING family represents a group of transmembrane-type E3 ubiquitin ligases, which has been characterized by an N-terminal transient signal peptide, a PA (protease-associated) domain, a TM (transmembrane) domain, as well as a C-terminal C3H2C3-type RING-H2 finger domain. It includes RNF13, RNF167, ZNRF4 (zinc and RING finger 4), GRAIL (gene related to anergy in lymphocytes)/RNF128, RNF130, RNF133, RNF148, RNF149 and RNF150 (which are more closely related), as well as RNF43 and ZNRF3, which have substantially longer C-terminal tail extensions compared with the others. PA-TM-RING proteins are expressed at low levels in all mammalian tissues and species, but they are not present in yeast. They play a common regulatory role in intracellular trafficking/sorting, suggesting that abrogation of their function may result in dysregulation of cellular signaling events in cancer.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQnSSTCPMCK 343
Cdd:cd16454     2 CAICLEEFKEGEKVRVLPCNHLFHKDCIDPWLEQ-HNTCPLCR 43

RING finger, H2 subclass, found in RING finger protein 103 (RNF103) and similar proteins; RNF103, also known as KF-1 or zinc finger protein 103 homolog (Zfp-103), is an endoplasmic reticulum (ER)-resident E3 ubiquitin-protein ligase that is widely expressed in many different organs, including brain, heart, kidney, spleen, and lung. It is involved in the ER-associated degradation (ERAD) pathway by interacting with components of the ERAD pathway, including Derlin-1 and VCP. RNF103 contains several hydrophobic regions at its N-terminal and middle regions, as well as a C-terminal C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSSTCPMCKGDVL 347
Cdd:cd16473     5 EECAICLENYQNGDLLRGLPCGHVFHQNCIDVWLERDNHCCPVCRWPVY 53

RING finger, H2 subclass, found in RING finger protein 13 (RNF13) and similar proteins; RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that is functionally significant in the regulation of cancer development, muscle cell growth, and neuronal development. Its expression is developmentally regulated during myogenesis and is upregulated in various tumors. RNF13 negatively regulates cell proliferation through its E3 ligase activity. It functions as an important regulator of inositol-requiring transmembrane kinase/endonuclease IRE1alpha, mediating endoplasmic reticulum (ER) stress-induced apoptosis through the activation of the IRE1alpha-TRAF2-JNK signaling pathway. Moreover, RNF13 is involved in the regulation of the soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) complex via the ubiquitination of snapin, a SNAP25-interacting protein, which thereby controls synaptic function. In addition, RNF13 participates in regulating the function of satellite cells by modulating cytokine composition. RNF13 is evolutionarily conserved among many metazoans and contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSSTCPMCKGDVL 347
Cdd:cd16796     9 DVCAICLDEYEEGDKLRILPCSHAYHCKCVDPWLTKTKKTCPVCKQKVV 57

RING finger, H2 subclass, found in rice E3 ubiquitin-protein ligase EL5 and similar proteins; EL5, also known as protein ELICITOR 5, is an E3 ubiquitin-protein ligase containing an N-terminal transmembrane domain and a C3H2C3-type RING-H2 finger that is a binding site for ubiquitin-conjugating enzyme (E2). It can be rapidly induced by N-acetylchitooligosaccharide elicitor. EL5 catalyzes polyubiquitination via the Lys48 residue of ubiquitin, and thus plays a crucial role as a membrane-anchored E3 in the maintenance of cell viability after the initiation of root primordial formation in rice. It also acts as an anti-cell death enzyme that might be responsible for mediating the degradation of cytotoxic proteins produced in root cells after the actions of phytohormones. Moreover, EL5 interacts with UBC5b, a rice ubiquitin carrier protein, through its RING-H2 finger. EL5 is an unstable protein, and its degradation is regulated by the C3H2C3-type RING-H2 finger in a proteasome-independent manner.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELP-CRHVFHKACVDPWLTQNsSTCPMC 342
Cdd:cd16461     2 CAICLSDYENGEELRRLPeCKHAFHKECIDEWLKSN-STCPLC 43

RING finger, H2 subclass, found in Arabidopsis thaliana protein SUGAR INSENSITIVE 3 (SIS3) and similar proteins; SIS3 is an E3 ubiquitin-protein ligase that acts as a positive regulator of sugar signaling during early seedling development. SIS3 contains a C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCKGDV 346
Cdd:cd23118     3 CTICLEDFEDGEKLRVLPCQHQFHSECVDQWLRRN-PKCPVCRRDA 47

RING finger, H2 subclass, found in RING finger protein 11 (RNF11) and similar proteins; RNF11 is an E3 ubiquitin-protein ligase that acts both as an adaptor and a modulator of itch-mediated control of ubiquitination events underlying membrane traffic. It acts downstream of an enzymatic cascade for the ubiquitination of specific substrates. It is also a molecular adaptor of homologous to E6-associated protein C-terminus (HECT)-type ligases. RNF11 has been implicated in the regulation of several signaling pathways. It enhances transforming growth factor receptor (TGFR) signaling by both abrogating Smurf2-mediated receptor ubiquitination and by promoting the Smurf2-mediated degradation of AMSH (associated molecule with the SH3 domain of STAM), a de-ubiquitinating enzyme that enhances TGF-beta signaling and epidermal growth factor receptor (EGFR) endosomal recycling. It also acts directly on Smad4 to enhance Smad4 function, and plays a role in prolonged TGF-beta signaling. RNF11 also functions as a critical component of the A20 ubiquitin-editing protein complex that negatively regulates tumor necrosis factor (TNF)-mediated nuclear factor (NF)-kappaB activation. It interacts with Smad anchor for receptor activation (SARA) and the endosomal sorting complex required for transport (ESCRT)-0 complex, thus participating in the regulation of lysosomal degradation of EGFR. RNF11 acts as a novel GGA cargo actively participating in regulating the ubiquitination of the GGA protein family. RNF11 functions together with TAX1BP1 to target TANK-binding kinase 1 (TBK1)/IkappaB kinase IKKi, and further restricts antiviral signaling and type I interferon (IFN)-beta production. RNF11 contains an N-terminal PPPY motif that binds WW domain-containing proteins such as AIP4/itch, Nedd4 and Smurf1/2 (SMAD-specific E3 ubiquitin-protein ligase 1/2), and a C-terminal C3H2C3-type RING-H2 finger that functions as a scaffold for the coordinated transfer of ubiquitin to substrate proteins together with the E2 enzymes UbcH527 and Ubc13.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQnSSTCPMCK 343
Cdd:cd16468     2 CVICMADFVVGDPIRYLPCMHIYHVDCIDDWLMR-SFTCPSCM 43

RING finger, H2 subclass, found in RING finger protein 130 (RNF130) and similar proteins; RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL). It is a transmembrane E3 ubiquitin-protein ligase expressed in leukocytes. It has a self-ubiquitination property, and controls the development of T cell clonal anergy by ubiquitination. RNF130 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCKGDVLE 348
Cdd:cd16803     1 DHCAVCIEGYKQNDVVRILPCKHVFHKSCVDPWLNEH-CTCPMCKLNILK 49

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6, RNF12, and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. RNF6 also regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. It acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF12, also known as LIM domain-interacting RING finger protein, or RING finger LIM domain-binding protein (R-LIM), is an E3 ubiquitin-protein ligase encoded by gene RLIM that is crucial for normal embryonic development in some species and for normal X inactivation in mice. It thus functions as a major sex-specific epigenetic regulator of female mouse nurturing tissues. RNF12 is widely expressed during embryogenesis, and mainly localizes to the cell nucleus, where it regulates the levels of many proteins, including CLIM, LMO, HDAC2, TRF1, SMAD7, and REX1, by proteasomal degradation. Both RNF6 and RNF12 contain a well conserved C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCK 343
Cdd:cd16467     2 CTICLGEYETGEKLRRLPCSHEFHSECVDRWLKEN-SSCPICR 43

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCK 343
Cdd:pfam13639   1 DECPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRSS-NTCPLCR 44

RING finger, H2 subclass, found in RING finger protein 149 (RNF149) and similar proteins; RNF149, also known as DNA polymerase-transactivated protein 2, is an E3 ubiquitin-protein ligase that interacts with wild-type v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), a RING domain-containing E3 ubiquitin ligase involved in control of gene transcription, translation, cytoskeletal organization, cell adhesion, and epithelial development. RNF149 induces the ubiquitination of wild-type BRAF and promotes its proteasome-dependent degradation. Mutated RNF149 has been found in some human breast, ovarian, and colorectal cancers. RNF149 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCKGDVLE 348
Cdd:cd16804     2 CAVCIENYKSKDVVRILPCKHVFHRICIDPWLLEH-RTCPMCKLDVIK 48

RING finger, H2 subclass, found in RING finger protein 181 (RNF181) and similar proteins; RNF181, also known as HSPC238, is a platelet E3 ubiquitin-protein ligase containing a C3H2C3-type RING-H2 finger. It interacts with the KVGFFKR motif of platelet integrin alpha(IIb)beta3, suggesting a role for RNF181-mediated ubiquitination in integrin and platelet signaling. It also suppresses the tumorigenesis of hepatocellular carcinoma (HCC) through the inhibition of extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling in the liver.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSStCPMCK 343
Cdd:cd16669     2 CPICLLEFEEGETVKQLPCKHSFHSDCILPWLGKTNS-CPLCR 43

RING finger, H2 subclass, found in protein E3 ubiquitin-protein ligase Praja-1, Praja-2, and similar proteins; This family includes two highly similar E3 ubiquitin-protein ligases, Praja-1 and Praja-2. Praja-1, also known as RING finger protein 70, is a RING-H2 finger ubiquitin ligase encoded by gene PJA1, a novel human X chromosome gene abundantly expressed in the brain. It has been implicated in bone and liver development, as well as memory formation and X-linked mental retardation (MRX). Praja-1 interacts with and activates the ubiquitin-conjugating enzyme UbcH5B, and shows E2-dependent E3 ubiquitin ligase activity. It is a 3-deazaneplanocin A (DZNep)-induced ubiquitin ligase that directly ubiquitinates individual polycomb repressive complex 2 (PRC2) subunits in a cell free system, which leads to their proteasomal degradation. It also plays an important role in neuronal plasticity, which is the basis for learning and memory. Moreover, Praja-1 ubiquitinates embryonic liver fodrin (ELF) and Smad3, but not Smad4, in a transforming growth factor-beta (TGF-beta)-dependent manner. It controls ELF abundance through ubiquitin-mediated degradation, and further regulates TGF-beta signaling, which plays a key role in the suppression of gastric carcinoma. Praja-1 also regulates the transcription function of the homeodomain protein Dlx5 by controlling the stability of Dlxin-1, via a ubiquitin-dependent degradation pathway. Praja-2, also known as RING finger protein 131, NEURODAP1, or KIAA0438, is an E2-dependent E3 ubiquitin ligase that interacts with and activates the ubiquitin-conjugating enzyme UbcH5B. It functions as an A-kinase anchoring protein (AKAP)-like E3 ubiquitin ligase that plays a critical role in controlling cyclic AMP (cAMP)-dependent PKA activity and pro-survival signaling, and further promotes cell proliferation and growth. Praja-2 is also involved in protein sorting at the postsynaptic density region of axosomatic synapses and possibly plays a role in synaptic communication and plasticity. Together with the AMPK-related kinase SIK2 and the CDK5 activator CDK5R1/p35, it forms a SIK2-p35-PJA2 complex that plays an essential role for glucose homeostasis in pancreatic beta cell functional compensation. Praja-2 ubiquitylates and degrades Mob, a core component of NDR/LATS kinase and a positive regulator of the tumor-suppressor Hippo signaling. Both Praja-1 and Praja-2 contain a potential nuclear localization signal (NLS) and a C-terminal C3H2C3-type RING-H2 motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:cd16465     2 CPICCSEYVKDEIATELPCHHLFHKPCITAWL-QKSGTCPVCR 43

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6 and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. Moreover, RNF6 regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 also binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. RNF6 also acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF6 contains an N-terminal coiled-coil domain, a Lys-X-X-Leu/Ile-X-X-Leu/Ile (KIL) motif, and a C-terminal C3H2C3-type RING-H2 finger which is responsible for its ubiquitin ligase activity. The KIL motif is present in a subset of RING-H2 proteins from organisms as evolutionarily diverse as human, mouse, chicken, Drosophila, Caenorhabditis elegans, and Arabidopsis thaliana.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCKGDVL 347
Cdd:cd16673     3 CSVCINEYATGNKLRRLPCAHEFHIHCIDRWLSEN-STCPICRQPVL 48

Modified RING finger, H2 subclass (C3H2C2D-type), found in zinc finger SWIM domain-containing protein 2 (ZSWIM2) and similar proteins; ZSWIM2, also known as MEKK1-related protein X (MEX) or ZZ-type zinc finger-containing protein 2, is a testis-specific E3 ubiquitin ligase that promotes death receptor-induced apoptosis through Fas, death receptor (DR) 3 and DR4 signaling. ZSWIM2 is self-ubiquitinated and targeted for degradation through the proteasome pathway. It acts as an E3 ubiquitin ligase, through the E2, Ub-conjugating enzymes UbcH5a, UbcH5c, or UbcH6. ZSWIM2 contains four putative zinc-binding domains including an N-terminal SWIM (SWI2/SNF2 and MuDR) domain critical for its ubiquitination, and two modified RING-H2 fingers separated by a ZZ zinc finger domain, which was required for interaction with UbcH5a and its self-association. This model corresponds to the second RING-H2 finger, which is not a canonical C3H2C3-type, but a modified C3H2C2D-type.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSSTCPMC 342
Cdd:cd16486     2 CRICLKAFQLGQHVRTLPCRHKFHRDCIDNWLLHSRNSCPID 43

RING finger, H2 subclass, found in Saccharomyces cerevisiae RING-H2 zinc finger protein RHA2B and similar proteins; RHA2B is an E3 ubiquitin-protein ligase involved in the positive regulation of abscisic acid (ABA) signaling and responses to salt and osmotic stresses during seed germination and early seedling development. It acts additively with RHA2A in regulating ABA signaling and drought response. RHA2B contains a C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSSTCPMCK 343
Cdd:cd23123     1 SDCCICLDKLKTGEEVKKLDCRHKFHKQCIEGWLKHLNFNCPLCR 45

RING finger, H2 subclass, found in RING finger protein 111 (RNF111) and similar proteins; RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It acts as an amplifier of Nodal signals, and enhances the dorsalizing activity of limiting amounts of Xnr1, a Nodal homolog, and requires Nodal signaling for its function. The loss of RNF111 results in early embryonic lethality, with defects attributed to compromised Nodal signaling. RNF111 also regulates tumor metastasis by modulation of the TGF-beta pathway. Its ubiquitination can be modulated by the four and a half LIM-only protein 2 (FHL2) that activates TGF-beta signal transduction. Furthermore, RNF111 interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. In addition, RNF111 has been identified as a small ubiquitin-like modifier (SUMO)-binding protein with clustered SUMO-interacting motifs (SIMs) that together form a SUMO-binding domain (SBD). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). The N-terminal half of RNF111 harbors three SIMs. Its C-terminal half show high sequence similarity with RING finger protein 165 (RNF165), where it contains two serine rich domains, two nuclear localization signals, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is required for polyubiqutination and proteasome-dependent degradation of phosphorylated forms of Smad2/3 and three major negative regulators of TGF-beta signaling, Smad7, SnoN and c-Ski.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1488160602 295 EELNDLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSStCPMCKGDV 346
Cdd:cd16681     7 EDTEEKCTICLSILEEGEDVRRLPCMHLFHQVCVDQWLITNKK-CPICRVDI 57

RING finger, H2 subclass, found in RING finger protein 165 (RNF165) and similar proteins; RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. RNF165 contains two serine rich domains, a nuclear localization signal, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is responsible for the enhancement of BMP-Smad1/5/8 signaling in the spinal cord.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1488160602 289 EKSDFTEElndlCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQnSSTCPMCKGDV 346
Cdd:cd16682     2 EESDTDEK----CTICLSMLEDGEDVRRLPCMHLFHQLCVDQWLAM-SKKCPICRVDI 54

RING finger, H2 subclass, found in RING finger proteins RNF38, RNF44, and similar proteins; This subfamily includes RING finger proteins RNF38, RNF44, and similar proteins. RNF38 is a nuclear E3 ubiquitin protein ligase that plays a role in regulating p53. RNF44 is an uncharacterized RING finger protein that shows high sequence similarity to RNF38. Both RNF38 and RNF44 contain a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), and a C3H2C3-type RING-H2 finger. In addition, RNF38 harbors two potential nuclear localization signals.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCK 343
Cdd:cd16472     5 CVVCMCDYEKRQLLRVLPCSHEFHAKCIDKWLKTN-RTCPICR 46

RING finger, H2 subclass, found in zinc/RING finger protein 3 (ZNRF3) and similar proteins; ZNRF3, also known as RING finger protein 203 (RNF203), is a homolog of Ring finger protein 43 (RNF43). It is a transmembrane E3 ubiquitin-protein ligase that is associated with the Wnt receptor complex, and negatively regulates Wnt signaling by promoting the turnover of frizzled and lipoprotein receptor-related protein LRP6 in an R-spondin-sensitive manner. It inhibits gastric cancer cell growth and promotes cell apoptosis by affecting the Wnt/beta-catenin/TCF signaling pathway. ZNRF3 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C3H2C3-type RING-H2 finger followed by a long C-terminal region.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCK 343
Cdd:cd16799     2 CAICLEKYIDGEELRVIPCTHRFHKKCVDPWLLQH-HTCPHCR 43

RING finger, H2 subclass, found in RING finger protein 24 (RNF24) and similar proteins; RNF24 is an intrinsic membrane protein localized in the Golgi apparatus. It specifically interacts with the ankyrin-repeats domains (ARDs) of TRPC1, -3, -4, -5, -6, and -7, and affects TRPC intracellular trafficking without affecting their activity. RNF24 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLtQNSSTCPMCKGDVLEVVPK 352
Cdd:cd16675     1 EICAVCLEEFKPKDELGICPCKHAFHRKCLIKWL-EVRKVCPLCNMPVLQLAQL 53

RING finger, H2 subclass, found in Arabidopsis thaliana RING-type E3 ubiquitin transferase BIG BROTHER (BB) and similar proteins; BB (also known as protein ENHANCER OF DA1-1 or EOD1) is an E3 ubiquitin-protein ligase that limits organ size, and possibly seed size, in a dose-dependent manner. It negatively regulates the duration of cell proliferation in leaves and petals independently of the major phytohormones (e.g. auxin, cytokinin, gibberellin, brassinosteroids, ethylene, abscisic acid, jasmonic acid), probably by targeting growth stimulators for degradation. It limits the proliferation of root meristematic cells. BB polyubiquitinates DA1. It is involved in the promotion of leaf senescence, in addition to its function in restricting plant growth. BB-related is an E3 ubiquitin-ligase probably involved in organ size regulation. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1488160602 298 NDLCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCKGDV 346
Cdd:cd23115     4 NERCVICRLEYEEGEDLLTLPCKHCYHSECIQQWLQIN-KVCPVCSAEV 51

RING finger, H2 subclass, found in Arabidopsis thaliana MED25-binding RING-H2 protein (MBR) and similar proteins; This subfamily includes MBR1 and MBR2 (also called HAL3-interacting protein 1 or AtHIP1). They are E3 ubiquitin-protein ligases that function as regulators of MED25 stability by targeting MED25 for degradation in a RING-H2-dependent manner. Proteasome-dependent degradation of MED25 seems to activate its function as a positive regulator of FLOWERING LOCUS T (FT) and is important to induce the expression of FT, and consequently to promote flowering. MBR2 may also function downstream of HAL3 and be required for HAL3-regulated plant growth. Activation of MBR2 by HAL3 may lead to the degradation of cell cycle suppressors, resulting in enhancement of cell division and plant growth. Both MBR1 and MBR2 contain a C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSStCPMCKGDVL 347
Cdd:cd23113     5 CCICQEEYEEGDELGTIECGHEYHSDCIKQWLVQKNL-CPICKATAL 50

RING finger, H2 subclass, found in TRAF-interacting protein (TRAIP) and similar proteins; TRAIP, also known as RING finger protein 206 (RNF206) or TRIP, is a ubiquitously expressed nucleolar E3 ubiquitin ligase important for cellular proliferation and differentiation. It is found near mitotic chromosomes and functions as a regulator of the spindle assembly checkpoint. TRAIP interacts with tumor necrosis factor (TNF)-receptor-associated factor (TRAF) proteins and inhibits TNF-alpha-mediated nuclear factor (NF)-kappaB activation. It also interacts with two tumor suppressors CYLD and spleen tyrosine kinase (Syk), and DNA polymerase eta, which facilitates translesional synthesis after DNA damage. TRAIP contains an N-terminal C3H2C2-type RING-H2 finger and an extended coiled-coil domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1488160602 300 LCPICIDEFDPGDELRELPCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:cd16480     1 YCTICSDFFDNSRDVAAIHCGHTFHYDCLLQWF-DTSRTCPQCR 43

Modified RING-CH finger, H2 subclass (C4HC2H-type), found in the ZNRF family; The ZNRF family includes zinc/RING finger proteins ZNRF1, ZNRF2, and similar proteins. It has been characterized by containing a unique combination of zinc finger-RING finger motifs in the C-terminal region, which is evolutionarily conserved in a wide range of species, including Caenorhabditis elegans and Drosophila. ZNRF proteins function as E3 ubiquitin ligases and are highly expressed in central nervous system (CNS) and peripheral nervous system (PNS) neurons, particularly during development and in adulthood. ZNRF1 and ZNRF2 are differentially localized within the synaptic region. ZNRF1 is associated with synaptic vesicle membranes, whereas ZNRF2 is present in presynaptic plasma membranes. They are N-myrisotoylated and also located in the endosome-lysosome compartment in fibroblasts. ZNRF proteins may play a role in the establishment and maintenance of neuronal transmission and plasticity via their ubiquitin ligase activity, as well as in regulating Ca2+-dependent exocytosis. The RING fingers found in ZNRF proteins are modified as C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of the RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSStCPM 341
Cdd:cd16489     2 CVICLEELEAGDTIARLPCLCIYHKKCIDDWFEVNRS-CPE 41

RING finger, H2 subclass, found in RING finger protein 38 (RNF38) and similar proteins; RNF38 is a nuclear E3 ubiquitin protein ligase that is widely expressed throughout the human body, and is especially highly expressed in the heart, brain, placenta and the testis. It recognizes p53 as a substrate for ubiquitination, and thus plays a role in regulating p53. The overexpression of RNF38 increases p53 ubiquitination and alters p53 localization. It is also capable of autoubiquitination. RNF38 expression is negatively regulated by the serotonergic system. Induction of RNF38 may be involved in the anxiety-like behavior or non-cell autonomy in Oryzias latipes by the decline of serotonin (5-HT) levels. RNF38 contains a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), a C3H2C3-type RING-H2 finger, as well as two potential nuclear localization signals.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 1488160602 300 LCPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNsSTCPMCKGD 345
Cdd:cd16679    22 LCVVCMCDFESRQLLRVLPCNHEFHAKCVDKWLKAN-RTCPICRAD 66

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 1488160602 298 NDLCPICIDEFDPGDELR--ELPCRHVFHKACVDPWLTQNSSTCPMCK 343
Cdd:cd16450     2 GNTCPICFEPWTSSGEHRlvSLKCGHLFGYSCIEKWLKGKGKKCPQCN 49

RING-H2 zinc finger domain; There are 8 cysteine/ histidine residues which are proposed to be the conserved residues involved in zinc binding. The protein, of which this domain is the conserved region, participates in diverse functions relevant to chromosome metabolism and cell cycle control.

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                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFD--------PGDE---LRELPCRHVFHKACVDPWLTQNsSTCPMC 342
Cdd:pfam12678   1 DTCAICRNPFMepcpecqaPGDDecpVVWGECGHAFHLHCISRWLKTN-NTCPLC 54

Modified RING-CH finger, H2 subclass (C4HC2H-type), found in zinc/RING finger protein 1 (ZNRF1) and similar proteins; ZNRF1, also known as Nerve injury-induced gene 283 protein (nin283), or peripheral nerve injury protein (PNIP), is an E3 ubiquitin-protein ligase that is highly expressed in the nervous system during development and is associated with synaptic vesicle membranes. It is N-myrisotoylated and is also located in the endosome-lysosome compartment in fibroblasts, suggesting it may participate in ubiquitin-mediated protein modification. It contains an N-terminal MAGE domain, and a special C-terminal domain that combines a zinc finger and a modified C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of the RING-H2 finger. Only the RING finger of the zinc finger-RING finger motif is required for its E3 ubiquitin ligase activity. ZNRF1 regulates Schwann cell differentiation by proteasomal degradation of glutamine synthetase (GS). It also mediates regulation of neuritogenesis via interaction with beta-tubulin type 2 (Tubb2). Moreover, ZNRF1 promotes Wallerian degeneration by degrading AKT to induce glycogen synthase kinase-3beta (GSK3B)-dependent CRMP2 phosphorylation. Furthermore, ZNRF1 and its sister protein ZNRF2 regulate the ubiquitous Na+/K+ pump (Na+/K+ATPase). In addition, ZNRF1 may be associated with leukemogenesis of acute lymphoblastic leukemia (ALL) with paired box domain gene 5 (PAX5) alteration.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSStCP 340
Cdd:cd16694     2 CVICLEELLQGDTIARLPCLCIYHKSCIDSWFEVNRS-CP 40

RING finger, H2 subclass, found in RING finger proteins RNF139, RNF145, and similar proteins; RNF139, also known as translocation in renal carcinoma on chromosome 8 protein (TRC8), is an endoplasmic reticulum (ER)-resident multi-transmembrane protein that functions as a potent growth suppressor in mammalian cells, inducing G2/M arrest, decreased DNA synthesis and increased apoptosis. It is a tumor suppressor that has been implicated in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control. A mutation in RNF139 has been identified in families with hereditary renal (RCC) and thyroid cancers. RNF145 is an uncharacterized RING finger protein encoded by the RNF145 gene, which is expressed in T lymphocytes, and its expression is altered in acute myelomonocytic and acute promyelocytic leukemias. Although its biological function remains unclear, RNF145 shows high sequence similarity with RNF139. Both RNF139 and RNF145 contain a C3H2C3-type RING-H2 finger with possible E3-ubiquitin ligase activity.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFDpgdELRELPCRHVFHKACVDPWL-TQNssTCPMC 342
Cdd:cd16476     1 DVCAICYQEMK---EARITPCNHFFHGLCLRKWLyVQD--TCPLC 40

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFDpgdELRELPCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:cd16532     1 DICPICQDEFK---DPVVLRCKHIFCEDCVSEWF-ERERTCPLCR 41

RING-CH finger, H2 subclass (C4HC3-type), found in E3 ubiquitin-protein ligase listerin and similar proteins; Listerin, also known as RING finger protein 160 or zinc finger protein 294, is the mammalian homolog of yeast Ltn1. It is widely expressed in all tissues, but motor and sensory neurons and neuronal processes in the brainstem and spinal cord are primarily affected in the mutant. Listerin is required for embryonic development and plays an important role in neurodegeneration. It also functions as a critical E3 ligase involving quality control of nonstop proteins. It mediates ubiquitylation of aberrant proteins that become stalled on ribosomes during translation. Ltn1 works with several cofactors to form a large ribosomal subunit-associated quality control complex (RQC), which mediates the ubiquitylation and extraction of ribosome-stalled nascent polypeptide chains for proteasomal degradation. It appears to first associate with nascent chain-stalled 60S subunits together with two proteins of unknown function, Tae2 and Rqc1. Listerin contains a long stretch of HEAT (Huntingtin, Elongation factor 3, PR65/A subunit of protein phosphatase 2A, and TOR) or ARM (Armadillo) repeats in the N terminus and middle region, and a catalytic RING-CH finger, also known as vRING or RINGv, with an unusual arrangement of zinc-coordinating residues in the C-terminus . Its cysteines and histidines are arranged in the sequence as C4HC3-type, rather than the C3H2C3-type in canonical RING-H2 finger.

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1488160602 301 CPICIDEFDPGDelRELP------CRHVFHKACVDPWL-TQNSSTCPMCK 343
Cdd:cd16491     3 CPICYSVIHGSN--HSLPklkcktCKNKFHSACLYKWFrSSNKSTCPLCR 50

Modified RING-CH finger, H2 subclass (C4HC2H-type), found in zinc/RING finger protein 2 (ZNRF2) and similar proteins; ZNRF2, also known as protein Ells2 or RING finger protein 202 (RNF202), is an E3 ubiquitin-protein ligase that is highly expressed in the nervous system during development and is present in presynaptic plasma membranes. It is N-myrisotoylated and is also located in the endosome-lysosome compartment in fibroblasts. It contains an N-terminal MAGE domain, and a special C-terminal domain that combines a zinc finger and a modified C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of RING-H2 finger. Only the RING finger of the zinc finger-RING finger motif is required for its E3 ubiquitin ligase activity. Together with its sister protein ZNRF1, ZNRF2 regulates the ubiquitous Na+/K+ pump (Na+/K+ATPase).

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSStCP 340
Cdd:cd16695    13 CAICLEELQQGDTIARLPCLCIYHKGCIDEWFEVNRS-CP 51

RING finger, H2 subclass, found in anaphase-promoting complex subunit 11 (APC11) and similar proteins; APC11, also known as cyclosome subunit 11, or hepatocellular carcinoma-associated RING finger protein, is a C3H2C3-type RING-H2 protein that facilitates ubiquitin chain formation by recruiting ubiquitin-charged ubiquitin conjugating enzymes (E2) through its RING-H2 domain. APC11 and its partner, the cullin-like subunit APC2, form the dynamic catalytic core of the gigantic, multisubunit 1.2-MDa anaphase-promoting complex/cyclosome (APC), also known as the cyclosome, which is a ubiquitin-protein ligase (E3) composed of at least 12 subunits and controls cell division by ubiquitinating cell cycle regulators, such as cyclin B and securin, to drive their timely degradation. APC11 can be inhibited by hydrogen peroxide, which may contribute to the delay in cell cycle progression through mitosis that is characteristic of cells subjected to oxidative stress. APC11 contains a canonical RING-H2-finger that coordinate two Zn2+ ions. In addition, it contains a third Zn2+-binding site that is not essential for its ligase activity.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1488160602 298 NDLCPICIDEFD--------PGDELrelP-----CRHVFHKACVDPWLTQNSST--CPMCKGD 345
Cdd:cd16456     1 DDVCGICRMAFDgccpdckfPGDDC---PlvwgkCSHCFHMHCILKWLNSQQVQqhCPMCRQE 60

RING finger, HC subclass, found in RING finger protein 213 (RNF213) and similar proteins; RNF213, also known as ALK lymphoma oligomerization partner on chromosome 17 or Moyamoya steno-occlusive disease-associated AAA+ and RING finger protein (mysterin), is an intracellular soluble protein that functions as an E3 ubiquitin-protein ligase and AAA+ ATPase, which possibly contributes to vascular development through mechanical processes in the cell. It plays a unique role in endothelial cells for proper gene expression in response to inflammatory signals from the environment. Mutations in RNF213 may be associated with Moyamoya disease (MMD), an idiopathic cerebrovascular occlusive disorder prevalent in East Asia. It also acts as a nuclear marker for acanthomorph phylogeny. RNF213 contains two tandem enzymatically active AAA+ ATPase modules and a C3HC4-type RING-HC finger. It can form a huge ring-shaped oligomeric complex.

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                  ....*....|....*....|....*....|....*....|....*..
gi 1488160602 301 CPICIDEF-DPgdelRELPCRHVFHKACVDPWLTQNsSTCPMCKGDV 346
Cdd:cd16561     5 CSICLEDLnDP----VKLPCDHVFCEECIRQWLPGQ-MSCPLCRTEL 46

RING finger, HC subclass, found in topoisomerase I-binding arginine/serine-rich protein (Topors) and similar proteins; Topors, also known as topoisomerase I-binding RING finger protein, tumor suppressor p53- binding protein 3, or p53-binding protein 3 (p53BP3), is a ubiquitously expressed nuclear E3 ubiquitin-protein ligase that can ligate both ubiquitin and small ubiquitin-like modifier (SUMO) to substrate proteins in the nucleus. It contains an N-terminal C3HC4-type RING-HC finger which ligates ubiquitin to its target proteins including DNA topoisomerase I, p53, NKX3.1, H2AX, and the AAV-2 Rep78/68 proteins. As a RING-dependent E3 ubiquitin ligase, Topors works with the E2 enzymes UbcH5a, UbcH5c, and UbcH6, but not with UbcH7, CDC34, or UbcH2b. Topors acts as a tumor suppressor in various malignancies. It regulates p53 modification, suggesting it may be responsible for astrocyte elevated gene-1 (AEG-1, also known as metadherin, or LYRIC) ubiquitin modification. Plk1-mediated phosphorylation of Topors inhibits Topors-mediated sumoylation of p53, whereas p53 ubiquitination is enhanced, leading to p53 degradation. It also functions as a negative regulator of the prostate tumor suppressor NKX3.1. Moreover, Topors is associated with promyelocytic leukemia nuclear bodies, and may be involved in the cellular response to camptothecin. It also plays a key role in the turnover of H2AX protein, discriminating the type of DNA damaging stress. Furthermore, Topors is a cilia-centrosomal protein associated with autosomal dominant retinal degeneration. Mutations in TOPORS cause autosomal dominant retinitis pigmentosa (adRP).

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                  ....*....|....*....|....*....|....*....|....*.
gi 1488160602 299 DLCPICIDEFDpgDELREL-PCRHVFHKACVDPWlTQNSSTCPMCK 343
Cdd:cd16574     2 SSCPICLDRFE--NEKAFLdGCFHAFCFTCILEW-SKVKNECPLCK 44

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 1488160602 301 CPICIDEFDPGDELrelPCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:cd23135     6 CSICFSEIRSGAIL---KCGHFFCLSCIASWL-REKSTCPLCK 44

RING finger, H2 subclass, found in Arabidopsis thaliana protein ABA INSENSITIVE RING PROTEIN 1 (AIRP1) and similar proteins; This subfamily includes Arabidopsis thaliana AIRP1 and RING-H2 finger B1a (RHB1A). AIRP1, also known as RING-type E3 ubiquitin transferase AIRP1, possesses E3 ubiquitin-protein ligase activity in vitro when associated with the E2 enzyme UBC8. It plays combinatory roles with AIRP2 in the positive regulation of the abscisic acid-mediated drought stress response. RHB1A is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

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                  ....*....|....*....|....*....|....*....|....
gi 1488160602 299 DLCPICIDEFDPGDELRELPCRHVFHKACVDPWLtQNSSTCPMC 342
Cdd:cd23116     3 DVCPTCLEGYTEENPKLLTKCGHHFHLACIYEWM-ERSERCPVC 45

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 1488160602 301 CPICIDEFDPGDELRELPCRHVFHKACVDPWLTQNSSTCPMC 342
Cdd:cd00162     1 CPICREEMNDRRPVVLLSCGHTFSRSAIARWLEGSKQKCPFC 42

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.

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                  ....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFDPGDELRElpCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:cd16506     1 DTCPICLDEIQNKKTLEK--CKHSFCEDCIDRAL-QVKPVCPVCG 42

Anaphase-promoting complex subunit 11 RING-H2 finger; Apc11 is one of the subunits of the anaphase-promoting complex or cyclosome. The APC subunits are cullin family proteins with ubiquitin ligase activity. Polyubiquitination marks proteins for degradation by the 26S proteasome and is carried out by a cascade of enzymes that includes ubiquitin-activating enzymes (E1s), ubiquitin-conjugating enzymes (E2s), and ubiquitin ligases (E3s). Apc11 acts as an E3 enzyme and is responsible for recruiting E2s to the APC and for mediating the subsequent transfer of ubiquitin to APC substrates in vivo. In Saccharomyces cerevisiae this RING-H2 finger protein defines the minimal ubiquitin ligase activity of the APC, and the integrity of the RING-H2 finger is essential for budding yeast cell viability.

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                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1488160602 298 NDLCPICIDEFD--------PGDELREL--PCRHVFHKACVDPWLTQNSST--CPMCK 343
Cdd:pfam12861  21 DDVCGICRVSFDgtcpdckfPGDDCPLVwgKCSHNFHMHCILKWLHTETSKglCPMCR 78

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        40
                  ....*....|....*....|....*....|....*....|....*
gi 1488160602 299 DLCPICIDEFDPGDELRElpCRHVFHKACVDPWLtQNSSTCPMCK 343
Cdd:cd16711     2 ETCPICLGEIQNKKTLDK--CKHSFCEDCITRAL-QVKKACPMCG 43