Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 15233720   122 ECAICLSEFVDKETLRwMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:pfam13639   2 ECPICLEEFEEGDKVV-VLPCGHHFHRECLDKWLRSSNTCPLCR 44

N1R/p28-like protein; Provisional

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 15233720   97 KELVESFPIFL--YSEVKGLKIGKggvECAICLSEFVDKET----LRWMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:PHA02929 152 KKFLKTIPSVLseYEKLYNRSKDK---ECAICMEKVYDKEIknmyFGILSNCNHVFCIECIDIWKKEKNTCPVCR 223

DNA repair protein rad18; All proteins in this family for which functions are known are involved in nucleotide excision repair.This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 15233720   123 CAIClSEFVDKETLrwmPPCSHTFHANCIDVWLSSQSTCPACRA 166
Cdd:TIGR00599  29 CHIC-KDFFDVPVL---TSCSHTFCSLCIRRCLSNQPKCPLCRA 68

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 15233720 122 ECAICLSEFVDKETLRwMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16454   1 TCAICLEEFKEGEKVR-VLPCNHLFHKDCIDPWLEQHNTCPLCR 43

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 15233720 122 ECAICLSEFVDKETLRwMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16472   4 QCVVCMCDYEKRQLLR-VLPCSHEFHAKCIDKWLKTNRTCPICR 46

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 15233720 122 ECAICLSEFVDKETLRwMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16467   1 ECTICLGEYETGEKLR-RLPCSHEFHSECVDRWLKENSSCPICR 43

RING finger, H2 subclass, found in Arabidopsis thaliana RING-H2 finger A1a (RHA1A), A1b (RHA1B) and similar proteins; This subfamily includes Arabidopsis thaliana RHA1A, RHA1B and XERICO. RHA1A is a probable E3 ubiquitin-protein ligase that may possess E3 ubiquitin ligase activity in vitro. RHA1B possesses E3 ubiquitin-protein ligase activity when associated with the E2 enzyme UBC8 in vitro. XERICO functions on abscisic acid homeostasis at post-translational level, probably through ubiquitin/proteasome-dependent substrate-specific degradation. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 15233720 122 ECAICLSEFVDKETLRWMPPCSHTFHANCIDVWL-SSQSTCPACRANL 168
Cdd:cd23121   3 CCAICLSDFNSDEKLRQLPKCGHIFHHHCLDRWIrYNKITCPLCRADL 50

H2 subclass of RING (RING-H2) fingers and its variants; 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). This family corresponds to the H2 subclass of RING (RING-H2) finger proteins that are characterized by containing C3H2C3-type canonical RING-H2 fingers or noncanonical RING-H2 finger variants, including C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type modified RING-H2 fingers. The canonical RING-H2 finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-H-X2-C-X(4-48)-C-X2-C, X is any amino acid and the number of X residues varies in different fingers. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-H2 finger can be found in 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 serves as a scaffold for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQS-TCPACR 165
Cdd:cd16448   1 CVICLEEFEEGDVVRLLP-CGHVFHLACILRWLESGNnTCPLCR 43

RING finger, H2 subclass, found in RING finger proteins RNF126, RNF115, and similar proteins; This subfamily includes RING finger proteins RNF126, RNF115, and similar proteins. RNF126 is a Bag6-dependent E3 ubiquitin ligase that is involved in the mislocalized protein (MLP) pathway of quality control. It regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). RNF126 promotes cancer cell proliferation by targeting the tumor suppressor p21 for ubiquitin-mediated degradation, and could be a novel therapeutic target in breast and prostate cancers. It is also able to ubiquitylate cytidine deaminase (AID), a poorly soluble protein that is essential for antibody diversification. RNF115, also known as Rab7-interacting ring finger protein (Rabring 7), or zinc finger protein 364 (ZNF364), or breast cancer-associated gene 2 (BCA2), is an E3 ubiquitin-protein ligase that is an endogenous inhibitor of adenosine monophosphate-activated protein kinase (AMPK) activation; this inhibition increases the efficacy of metformin in breast cancer cells. It also functions as a cofactor in the restriction imposed by tetherin on HIV-1, and targets HIV-1 Gag for lysosomal degradation, impairing virus assembly and release, in a tetherin-independent manner. Moreover, RNF115 is a Rab7-binding protein that stimulates c-Myc degradation through mono-ubiquitination of MM-1. It also plays crucial roles as a Rab7 target protein in vesicle traffic to late endosome/lysosome and lysosome biogenesis. RNF115 and RNF126 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. Both of them contain an N-terminal BCA2 Zinc-finger domain (BZF), AKT-phosphorylation sites, and a C-terminal C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 15233720 122 ECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16667   1 ECAVCKEDFEVGEEVRQLP-CKHLFHPDCIVPWLELHNSCPVCR 43

RING finger, H2 subclass, found in Arabidopsis thaliana NEP1-interacting protein-like 1 (NIPL1) and similar proteins; This subfamily includes Arabidopsis thaliana NIPL1 and MISFOLDED PROTEIN SENSING RING E3 LIGASE 1 (MPSR1). NIPL1, also called RING-H2 finger protein ATL27, may be involved in the early steps of the plant defense signaling pathway. MPSR1 is a cytoplasmic E3 ubiquitin-protein ligase involved in protein quality control (PQC) under proteotoxic stress. It is essential for plant survival under proteotoxic stress. It functions by removing damaged proteins before they form cytotoxic aggregates. It recognizes misfolded proteins selectively and tethers polyubiquitin chains to the proteins directly for subsequent degradation by the 26S proteasome pathway. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 15233720 122 ECAICLSEFVDKETLRWMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd23119   1 CCTICLQDLQVGEIARSLPHCHHTFHLGCVDKWLGRHGSCPVCR 44

RING finger, H2 subclass, found in RING finger protein 167 (RNF167) and similar proteins; RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) ubiquitination. It ubiquitinates AMPA-type glutamate receptor subunit GluA2 and regulates its surface expression, and thus acts as a selective regulator of AMPAR-mediated neurotransmission. It acts as an endosomal membrane protein which ubiquitylates vesicle-associated membrane protein 3 (VAMP3) and regulates endosomal trafficking. Moreover, RNF167 plays a role in the regulation of TSSC5 (tumor-suppressing subchromosomal transferable fragment cDNA, also known as ORCTL2/IMPT1/BWR1A/SLC22A1L), which can function in concert with the ubiquitin-conjugating enzyme UbcH6. RNF167 is widely conserved in metazoans and contains an N-terminal signal peptide, a protease-associated (PA) domain, two transmembrane domains (TM1 and TM2), and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLS-SQSTCPACR 165
Cdd:cd16797   3 CAICLDEYEEGDKLRVLP-CSHAYHSKCVDPWLTqTKKTCPVCK 45

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 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16673   3 CSVCINEYATGNKLRRLP-CAHEFHIHCIDRWLSENSTCPICR 44

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 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16465   2 CPICCSEYVKDEIATELP-CHHLFHKPCITAWLQKSGTCPVCR 43

RING finger, H2 subclass, found in RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), and similar proteins; This subfamily includes RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), Zinc/RING finger protein 4 (ZNRF4), and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane domain (TM), and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that functions 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. RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in the ubiquitination of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). It acts as an endosomal membrane protein which ubiquitylates vesicle-associated membrane protein 3 (VAMP3) and regulates endosomal trafficking. Moreover, RNF167 plays a role in the regulation of TSSC5 (tumor-suppressing subchromosomal transferable fragment cDNA, also known as ORCTL2/IMPT1/BWR1A/SLC22A1L), which can function in concert with the ubiquitin-conjugating enzyme UbcH6. ZNRF4, also known as RING finger protein 204 (RNF204), or Nixin, is an endoplasmic reticulum (ER) membrane-anchored ubiquitin ligase that physically interacts with the ER-localized chaperone calnexin in a glycosylation-independent manner, inducing calnexin ubiquitination, and p97-dependent degradation. The murine protein sperizin (spermatid-specific ring zinc finger) is a homolog of human ZNRF4. It is specifically expressed in Haploid germ cells and is involved in spermatogenesis.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQ-STCPACR 165
Cdd:cd16665   3 CAICLDDYEEGDKLRILP-CSHAYHCKCIDPWLTKNkRTCPVCK 45

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 15233720 122 ECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRANL 168
Cdd:cd16669   1 KCPICLLEFEEGETVKQLP-CKHSFHSDCILPWLGKTNSCPLCRHEL 46

RING finger, H2 subclass, found in RING finger proteins RNF24, RNF122, and similar proteins; This subfamily includes RNF24, RNF122, 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. RNF122 is a RING finger protein associated with HEK 293T cell viability. It is localized to the endoplasmic reticulum (ER) and the Golgi apparatus, and overexpressed in anaplastic thyroid cancer cells. RNF122 functions as an E3 ubiquitin ligase that can ubiquitinate itself and undergo degradation through its RING finger in a proteasome-dependent manner. Both RNF24 and RNF122 contain an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 15233720 123 CAICLSEFVDKETLRwMPPCSHTFHANCIDVWLSSQSTCPACRA 166
Cdd:cd16469   3 CAVCLEEFKLKEELG-VCPCGHAFHTKCLKKWLEVRNSCPICKS 45

RING finger, H2 subclass, found in RING finger proteins, RNF130, RNF149, RNF150 and similar proteins; This subfamily includes RING finger proteins, RNF130, RNF149 and RNF150, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by 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. RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128. 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. RNF133 is a testis-specific endoplasmic reticulum-associated E3 ubiquitin ligase that may play a role in sperm maturation through an ER-associated degradation (ERAD) pathway. RNF149, also known as DNA polymerase-transactivated protein 2, is an E3 ubiquitin-protein ligase that induces the ubiquitination of wild-type v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) and promotes its proteasome-dependent degradation. RNF150 polymorphisms may be associated with chronic obstructive pulmonary disease (COPD) risk in the Chinese population. This subfamily also includes Drosophila melanogaster protein goliath (d-goliath), also known as protein g1, which is one of the founding members of the group. It was originally identified as a transcription factor involved in the embryo mesoderm formation.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRANL 168
Cdd:cd16668   2 CAVCIEPYKPSDVIRILP-CKHIFHKSCVDPWLLEHRTCPMCKLDI 46

RING finger, H2 subclass, found in RING finger protein 115 (RNF115) and similar proteins; RNF115, also known as Rab7-interacting ring finger protein (Rabring 7), or zinc finger protein 364 (ZNF364), or breast cancer-associated gene 2 (BCA2), is an E3 ubiquitin-protein ligase that is an endogenous inhibitor of adenosine monophosphate-activated protein kinase (AMPK) activation and its inhibition increases the efficacy of metformin in breast cancer cells. It also functions as a co-factor in the restriction imposed by tetherin on HIV-1, and targets HIV-1 Gag for lysosomal degradation, impairing virus assembly and release, in a tetherin-independent manner. Moreover, RNF115 is a Rab7-binding protein that stimulates c-Myc degradation through mono-ubiquitination of MM-1. It also plays crucial roles as a Rab7 target protein in vesicle traffic to late endosome/lysosome and lysosome biogenesis. Furthermore, RNF115 and the related protein, RNF126 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. RNF115 contains an N-terminal BCA2 Zinc-finger domain (BZF), the AKT-phosphorylation sites, and the C-terminal C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 15233720 121 VECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRANLS 169
Cdd:cd16800   1 LECPVCKEDYTVGEQVRQLP-CNHFFHSDCIVPWLELHDTCPVCRKSLN 48

RING-like zinc finger;

                          10        20        30
                  ....*....|....*....|....*....|
gi 15233720   122 ECAICLSEFVDKETLRwMPPCSHTFHANCI 151
Cdd:pfam17123   1 ECSICLDEFKPGQALF-VLPCSHVFHYKCI 29

RING finger, H2 subclass, found in DAZ (deleted in azoospermia)-interacting protein 3 (DZIP3) and similar proteins; DZIP3, also known as RNA-binding ubiquitin ligase of 138 kDa (RUL138) or 2A-HUB protein, is an RNA-binding E3 ubiquitin-protein ligase that interacts with coactivator-associated arginine methyltransferase 1 (CARM1) and acts as a transcriptional coactivator of estrogen receptor (ER) alpha. It is also a histone H2A ubiquitin ligase that catalyzes monoubiquitination of H2A at lysine 119, functioning as a combinatorial component of the repression machinery required for repressing a specific chemokine gene expression program, critically modulating migratory responses to Toll-like receptors (TLR) activation. DZIP3 contains a C3H2C3-type RING-H2 finger at the C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 15233720 123 CAICLSEFVDKETLrwMP-PCSHTFHANCIDVWLSSQSTCPACRA 166
Cdd:cd16460   3 CVICHEAFSDGDRL--LVlPCAHKFHTQCIGPWLDGQQTCPTCRL 45

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 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16804   2 CAVCIENYKSKDVVRILP-CKHVFHRICIDPWLLEHRTCPMCK 43

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
                ....*....|....*....|....*....|....*....|....*..
gi 15233720 122 ECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRANL 168
Cdd:cd16681  12 KCTICLSILEEGEDVRRLP-CMHLFHQVCVDQWLITNKKCPICRVDI 57

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 15233720 119 GGVECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRA 166
Cdd:cd23115   3 DNERCVICRLEYEEGEDLLTLP-CKHCYHSECIQQWLQINKVCPVCSA 49

RING finger, H2 subclass, found in Tetratricopeptide repeat protein 3 (TTC3) and similar proteins; TTC3, also known as protein DCRR1, TPR repeat protein D, TPR repeat protein 3, or RING finger protein 105 (RNF105), is an E3 ubiquitin-protein ligase encoded by a gene within the Down syndrome (DS) critical region on chromosome 21. It affects differentiation and Golgi compactness in neurons through specific actin-regulating pathways. It inhibits the neuronal-like differentiation of pheocromocytoma cells by activating RhoA and by binding to Citron proteins. TTC3 is an Akt-specific E3 ligase that binds to phosphorylated Akt and facilitates its ubiquitination and degradation within the nucleus. It contains four N-terminal TPR motifs, a potential coiled-coil region and a Citron binding region in the central part, and a C-terminal C3H2C2-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 15233720 123 CAICLSEFVDKETLRWmpPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16481   2 CIICHDDLKPDQLAKL--ECGHIFHKECIKQWLKEQSTCPTCR 42

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 15233720 122 ECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLS-SQSTCPACR 165
Cdd:cd16486   1 QCRICLKAFQLGQHVRTLP-CRHKFHRDCIDNWLLhSRNSCPIDG 44

RING finger, H2 subclass, found in RING finger protein 128 (RNF128) and similar proteins; This subfamily includes RING finger proteins RNF128, RNF133, RNF148, and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL), is a type 1 transmembrane E3 ubiquitin-protein ligase that is a critical regulator of adaptive immunity and development. It inhibits cytokine gene transcription, is expressed in anergic CD4+ T cells, and has been implicated in primary T cell activation, survival, and differentiation, as well as in T cell anergy and oral tolerance. It induces T cell anergy through the ubiquitination activity of its cytosolic RING finger. It regulates expression of the costimulatory molecule CD40L on CD4 T cells, and ubiquitinates the costimulatory molecule CD40 ligand (CD40L) during the induction of T cell anergy. Moreover, RNF128 interacts with the luminal/extracellular portion of both CD151 and the related tetraspanin CD81 via its PA domain, which promoted ubiquitination of cytosolic lysine residues. It also down-modulates the expression of CD83 (previously described as a cell surface marker for mature dendritic cells) on CD4 T cells. Furthermore, Rho guanine dissociation inhibitor (RhoGDI) has been identified as a potential substrate of RNF128, suggesting a role for Rho effector molecules in T cell anergy. In addition, RNF128 plays a role in environmental stress responses. It promotes environmental salinity tolerance in euryhaline tilapia. RNF133 is a testis-specific endoplasmic reticulum-associated E3 ubiquitin ligase that is mainly present in the cytoplasm of elongated spermatids. It may play a role in sperm maturation through an ER-associated degradation (ERAD) pathway. RNF148 is a testis-specific E3 ubiquitin ligase that is abundantly expressed in testes and slightly expressed in pancreas. Its expression is regulated by histone deacetylases.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRANL 168
Cdd:cd16802   3 CAVCIEPYKPNDVVRILT-CNHLFHKNCIDPWLLEHRTCPMCKCDI 47

RING finger, H2 subclass, found in synoviolin and similar proteins; Synoviolin, also known as synovial apoptosis inhibitor 1 (Syvn1), Hrd1, or Der3, is an endoplasmic reticulum (ER)-anchoring E3 ubiquitin ligase that functions as a suppressor of ER stress-induced apoptosis and plays a role in homeostasis maintenance. It also targets tumor suppressor gene p53 for proteasomal degradation, suggesting crosstalk between ER associated degradation (ERAD) and p53 mediated apoptotic pathway under ER stress. Moreover, synoviolin controls body weight and mitochondrial biogenesis through negative regulation of the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1beta. It upregulates amyloid beta production by targeting a negative regulator of gamma-secretase, Retention in endoplasmic reticulum 1 (Rer1), for degradation. It is also involved in the degradation of endogenous immature nicastrin, and affects amyloid beta-protein generation. Moreover, synoviolin is highly expressed in rheumatoid synovial cells and may be involved in the pathogenesis of rheumatoid arthritis (RA). It functions as an anti-apoptotic factor that is responsible for the outgrowth of synovial cells during the development of RA. It promotes inositol-requiring enzyme 1 (IRE1) ubiquitination and degradation in synovial fibroblasts with collagen-induced arthritis. Furthermore, the upregulation of synoviolin may represent a protective response against neurodegeneration in Parkinson's disease (PD). In addition, synoviolin is involved in liver fibrogenesis. Synoviolin contains a C3H2C2-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 15233720 123 CAICLSEFVDKETLrwmPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16479   4 CIICREEMTVGAKK---LPCGHIFHLSCLRSWLQRQQTCPTCR 43

RING finger, H2 subclass, found in RING finger protein 150 (RNF150) and similar proteins; RNF150 is a RING finger protein and its polymorphisms may be associated with chronic obstructive pulmonary disease (COPD) risk in the Chinese population. Further studies with larger numbers of participants worldwide are needed for validation of the relationships between RNF150 genetic variants and the pathogenesis of COPD. RNF150 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 15233720 123 CAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCPACRANL 168
Cdd:cd16805   9 CAVCIEGYKPNDVVRILP-CRHLFHKSCVDPWLLDHRTCPMCKMNI 53

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 15233720 123 CAICLSEFvdkeTLRWMPPCSHTFHANCIDVWLSSQSTCPAC 164
Cdd:cd16476   3 CAICYQEM----KEARITPCNHFFHGLCLRKWLYVQDTCPLC 40

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).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 15233720 120 GVECAICLSEFVDKETLrwMPPCSHTFHANCIDVWLSSQSTCPACRA 166
Cdd:cd16574   1 DSSCPICLDRFENEKAF--LDGCFHAFCFTCILEWSKVKNECPLCKQ 45

RING finger, HC subclass, found in tripartite motif-containing protein TRIM65 and similar proteins; TRIM65 is an E3 ubiquitin-protein ligase that interacts with the innate immune receptor MDA5, enhancing its ability to stimulate interferon-beta signaling. It functions as a potential oncogenic protein that negatively regulates p53 through ubiquitination, providing insight into the development of novel approaches targeting TRIM65 for non-small cell lung carcinoma (NSCLC) treatment, and also overcoming chemotherapy resistance. Moreover, TRIM65 negatively regulates microRNA-driven suppression of mRNA translation by targeting TNRC6 proteins for ubiquitination and degradation. TRIM65 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 15233720 123 CAICLSEFVDKETLrwmpPCSHTFHANCI-DVW---LSSQSTCPACRANLSLKPG 173
Cdd:cd16609   6 CSICLGLYQDPVTL----PCQHSFCRACIeDHWrqkDEGSFSCPECRAPFPEGPT 56

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 15233720    123 CAICLSEFVDKetLRWMPpCSHTFHANCIDVWLSSQS-TCPAC 164
Cdd:smart00184   1 CPICLEEYLKD--PVILP-CGHTFCRSCIRKWLESGNnTCPIC 40

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 15233720 122 ECAICLSEFVDKETLRWMPpCSHTFHANCIDVWLSSQSTCP 162
Cdd:cd16489   1 ECVICLEELEAGDTIARLP-CLCIYHKKCIDDWFEVNRSCP 40

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 15233720 123 CAICLSEFVDKETLRwmpPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16711   4 CPICLGEIQNKKTLD---KCKHSFCEDCITRALQVKKACPMCG 43

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 15233720 123 CAICLSEFVDKETLRwmppCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16532   3 CPICQDEFKDPVVLR----CKHIFCEDCVSEWFERERTCPLCR 41

RING finger, H2 subclass, found in BRCA1-associated protein (BRAP2) and similar proteins; BRAP2, also known as impedes mitogenic signal propagation (IMP), RING finger protein 52, or renal carcinoma antigen NY-REN-63, is a novel cytoplasmic protein interacting with the two functional nuclear localization signal (NLS) motifs of BRCA1, a nuclear protein linked to breast cancer. It also binds to the SV40 large T antigen NLS motif and the bipartite NLS motif found in mitosin. BRAP2 serves as a cytoplasmic retention protein and plays a role in the regulation of nuclear protein transport. It contains an N-terminal RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by a C3H2C3-type RING-H2 finger and a UBP-type zinc finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 15233720 123 CAICLSEFVDKETLRWMPPCSHTFHANCIDVWLssQSTCPACR 165
Cdd:cd16457   3 CPVCLERMDESVSGILTILCNHSFHCSCLSKWG--DSSCPVCR 43

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
                ....*....|....*....|....*...
gi 15233720 142 CSHTFHANCIDVWLSSQS---TCPACRA 166
Cdd:cd16456  32 CSHCFHMHCILKWLNSQQvqqHCPMCRQ 59

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 15233720 123 CAICLSEFVDKETLrwmpPCSHTFHANCI----DVWLSSQSTCPACRANLSLKP 172
Cdd:cd16597   8 CSICLELFKDPVTL----PCGHNFCGVCIektwDSQHGSEYSCPQCRATFPRRP 57

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 15233720 121 VECAICLSEFvdkeTLRWMPPCSHTFHANCIDVWLSSQSTCPACR 165
Cdd:cd23135   4 LSCSICFSEI----RSGAILKCGHFFCLSCIASWLREKSTCPLCK 44

RING finger, H2 subclass, found in Arabidopsis thaliana RING-H2 zinc finger protein RHF2A and similar proteins; RHF2A is an E3 ubiquitin-protein ligase involved in the positive regulation of the gametogenesis progression. It is required for the degradation of KRP6, a cyclin-dependent kinase inhibitor which accumulates during meiosis and blocks the progression of subsequent mitoses during gametophytes development. It functions in association with RHF1A. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 15233720 118 KGGVE------CAICLSEFVDKETLRwMPPCSHTFHANCIDVWLSSQSTCPACRANLSLK 171
Cdd:cd23122   3 EGGIQdacedaCSICLESFCEADPAT-VTSCKHEYHLQCILEWSQRSKECPMCWQALSLK 61

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 15233720   123 CAICLSEFVDKETlrwMPPCSHTFHANCIDVWLSSQS-TCPAC 164
Cdd:pfam00097   1 CPICLEEPKDPVT---LLPCGHLFCSKCIRSWLESGNvTCPLC 40

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 15233720 122 ECAICLSEFvDKETLRWMPPCSHTFHANCIDVWLSSQSTCPAC 164
Cdd:cd23116   4 VCPTCLEGY-TEENPKLLTKCGHHFHLACIYEWMERSERCPVC 45

first RING finger, H2 subclass, found in RING finger protein 32 (RNF32) and similar proteins; RNF32 is mainly expressed in testis spermatogenesis, most likely in spermatocytes and/or in spermatids, suggesting a possible role in sperm formation. RNF32 contains two C3H2C3-type RING-H2 fingers separated by an IQ domain of unknown function. Although the biological function of RNF32 remains unclear, proteins with double RING-H2 fingers may act as scaffolds for binding several proteins that function in the same pathway. This model corresponds to the first RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 15233720 123 CAICLSEFVDKETLrwMPPCSHTFHANCIDVW--LSSQSTCPACRAN 167
Cdd:cd16677   2 CPICLEDFGLQQQV--LLSCSHVFHRACLESFerFSGKKTCPMCRKE 46

Component of SCF ubiquitin ligase and anaphase-promoting complex [Posttranslational modification, protein turnover, chaperones / Cell division and chromosome partitioning];

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 15233720 123 CAICLSEFVDK--ETLRWMPP----------CSHTFHANCIDVWLSSQSTCPACR 165
Cdd:COG5194  23 CAICRNHIMGTcpECQFGMTPgdecpvvwgvCNHAFHDHCIYRWLDTKGVCPLDR 77

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 15233720 122 ECAICLSEFVDKETLRwmppCSHTFHANCIDVWLSSQSTCPACRANL 168
Cdd:cd16535   3 QCSICSELFIEAVTLN----CSHSFCSYCITEWMKRKKECPICRKPI 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 15233720 123 CAICLSEFVDKETLRWmPPCSHTFHANCIDVWL-SSQSTCPAC 164
Cdd:cd00162   1 CPICREEMNDRRPVVL-LSCGHTFSRSAIARWLeGSKQKCPFC 42

RING finger, HC subclass, found in RING finger protein 219 (RNF219) and similar proteins; RNF219 may function as a modulator of late-onset Alzheimer's disease (LOAD) associated amyloid beta A4 precursor protein (APP) endocytosis and metabolism. It genetically interacts with apolipoprotein E epsilon4 allele (APOE4). Thus, a genetic variant of RNF219 was found to affect amyloid deposition in human brain and LOAD age-of-onset. Moreover, common genetic variants at the RNF219 locus had been associated with alternations in lipid metabolism, cognitive performance and central nervous system ventricle volume. RNF219 contains a C3HC4-type RING-HC finger.

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gi 15233720 121 VECAICLSEfVDKETLrwmppCS--HTFHANCIDVWLSSQSTCPACR 165
Cdd:cd16562   2 ISCHICLGK-VRQPVI-----CSnnHVFCSSCMDVWLKNNNQCPACR 42