PA _GRAIL_like: Protease-associated (PA) domain GRAIL-like. This group includes PA domain containing E3 (ubiquitin ligases) similar to human GRAIL (gene related to anergy in lymphocytes) protein. Proteins in this group contain a C3H2C3 RING finger. E3 ubiquitin ligase is part of an enzymic cascade, the end result of which is the ubiquitination of proteins. In this cascade, E1 activates the ubiquitin, the activated ubiquitin is carried by E2, and E3 recognizes the acceptor protein as well as catalyzes the transfer of the activated ubiquitin from E2 to this acceptor. GRAIL, a transmembrane protein localized in the endosomes, controls the development of T cell clonal anergy, and may ubiquitinate membrane-associated targets for T cell activation. GRAIL1 is associated with, and regulated by, two isoforms of otubain 1 (the ubiquitin-specific protease). Additional E3s belonging to this group include human (h)Goliath and Xenopus GREUL1 (Goliath Related E3 Ubiquitin Ligase 1). hGoliath and GRAIL both have the property of self-ubiquitination. hGoliath is expressed in leukocytes; its expression and localization is not modified in leukemia. GREUL1 may play a role in the generation of anterior ectoderm. The significance of the PA domain to these proteins has not been ascertained. It may be a protein-protein interaction domain. At peptidase active sites, the PA domain may participate in substrate binding and/or promoting conformational changes, which influence the stability and accessibility of the site to substrate.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878  45 NITYLEPEPGaavagsgggaELHTEKSECGRYGEHSPKQDARGEVVMASSAQDRLACDPNTKFAAPAHGKHWIALIPKGN 124
Cdd:cd02122     1 NITYVDPISN----------ELTTEKTESGRYGEHSPKEEAKGLVVVPDPPNDHYGCDPDTRFPIPPNGEPWIALIQRGN 70

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1907189878 125 CTYRDKIRNAFLQNASAVVIFNVGSNTNETITMPHAGVEDIVAIMIPEPKGKEIVSLLERNITVTMYI 192
Cdd:cd02122    71 CTFEEKIKLAAERNASAVVIYNNPGTGNETVKMSHPGTGDIVAIMITNPKGMEILELLERGISVTMVI 138

PA _GRAIL_like: Protease-associated (PA) domain GRAIL-like. This group includes PA domain containing E3 (ubiquitin ligases) similar to human GRAIL (gene related to anergy in lymphocytes) protein. Proteins in this group contain a C3H2C3 RING finger. E3 ubiquitin ligase is part of an enzymic cascade, the end result of which is the ubiquitination of proteins. In this cascade, E1 activates the ubiquitin, the activated ubiquitin is carried by E2, and E3 recognizes the acceptor protein as well as catalyzes the transfer of the activated ubiquitin from E2 to this acceptor. GRAIL, a transmembrane protein localized in the endosomes, controls the development of T cell clonal anergy, and may ubiquitinate membrane-associated targets for T cell activation. GRAIL1 is associated with, and regulated by, two isoforms of otubain 1 (the ubiquitin-specific protease). Additional E3s belonging to this group include human (h)Goliath and Xenopus GREUL1 (Goliath Related E3 Ubiquitin Ligase 1). hGoliath and GRAIL both have the property of self-ubiquitination. hGoliath is expressed in leukocytes; its expression and localization is not modified in leukemia. GREUL1 may play a role in the generation of anterior ectoderm. The significance of the PA domain to these proteins has not been ascertained. It may be a protein-protein interaction domain. At peptidase active sites, the PA domain may participate in substrate binding and/or promoting conformational changes, which influence the stability and accessibility of the site to substrate.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878  45 NITYLEPEPGaavagsgggaELHTEKSECGRYGEHSPKQDARGEVVMASSAQDRLACDPNTKFAAPAHGKHWIALIPKGN 124
Cdd:cd02122     1 NITYVDPISN----------ELTTEKTESGRYGEHSPKEEAKGLVVVPDPPNDHYGCDPDTRFPIPPNGEPWIALIQRGN 70

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1907189878 125 CTYRDKIRNAFLQNASAVVIFNVGSNTNETITMPHAGVEDIVAIMIPEPKGKEIVSLLERNITVTMYI 192
Cdd:cd02122    71 CTFEEKIKLAAERNASAVVIYNNPGTGNETVKMSHPGTGDIVAIMITNPKGMEILELLERGISVTMVI 138

myxosortase-dependent M36 family metallopeptidase; Members of this bacterial protein family have an M36 family metallopeptidase domain, like fungalysin (see PF02128), and a C-terminal MYXO-CTERM domain (see TIGR03901), suggesting processing and surface-anchoring by the still-unknown putative transpeptidase, myxosortase. Members of this family include MXAN_3564 (mepA), part of the effector cargo of outer membrane vesicles that the species produces in large numbers during predation on other microbes.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878   84 DARGEVVMASSA--QDRLACDPNTKfAAPAHGKhwIALIPKGNCTYRDKIRNAflQNASA--VVIFN--VGS-----NTN 152
Cdd:NF038112   516 DVTGDVVLAPDGtgSDTDGCTPFTN-AAEVAGK--IALIDRGTCDFTVKALNA--QNAGAigVIIANnaAGAapglgGTD 590

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|
gi 1907189878  153 ETITMPhagvedivAIMIPEPKGKEIVS-LLERNITVTMY 191
Cdd:NF038112   591 PAVTIP--------ALSITQADGNAWKAaLANGPVTVRLR 622

RING-like zinc finger;

                          10        20
                  ....*....|....*....|....*
gi 1907189878 289 NCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:pfam17123   1 ECSICLDEFKPGQALFVLPCSHVFH 25

PA _GRAIL_like: Protease-associated (PA) domain GRAIL-like. This group includes PA domain containing E3 (ubiquitin ligases) similar to human GRAIL (gene related to anergy in lymphocytes) protein. Proteins in this group contain a C3H2C3 RING finger. E3 ubiquitin ligase is part of an enzymic cascade, the end result of which is the ubiquitination of proteins. In this cascade, E1 activates the ubiquitin, the activated ubiquitin is carried by E2, and E3 recognizes the acceptor protein as well as catalyzes the transfer of the activated ubiquitin from E2 to this acceptor. GRAIL, a transmembrane protein localized in the endosomes, controls the development of T cell clonal anergy, and may ubiquitinate membrane-associated targets for T cell activation. GRAIL1 is associated with, and regulated by, two isoforms of otubain 1 (the ubiquitin-specific protease). Additional E3s belonging to this group include human (h)Goliath and Xenopus GREUL1 (Goliath Related E3 Ubiquitin Ligase 1). hGoliath and GRAIL both have the property of self-ubiquitination. hGoliath is expressed in leukocytes; its expression and localization is not modified in leukemia. GREUL1 may play a role in the generation of anterior ectoderm. The significance of the PA domain to these proteins has not been ascertained. It may be a protein-protein interaction domain. At peptidase active sites, the PA domain may participate in substrate binding and/or promoting conformational changes, which influence the stability and accessibility of the site to substrate.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878  45 NITYLEPEPGaavagsgggaELHTEKSECGRYGEHSPKQDARGEVVMASSAQDRLACDPNTKFAAPAHGKHWIALIPKGN 124
Cdd:cd02122     1 NITYVDPISN----------ELTTEKTESGRYGEHSPKEEAKGLVVVPDPPNDHYGCDPDTRFPIPPNGEPWIALIQRGN 70

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1907189878 125 CTYRDKIRNAFLQNASAVVIFNVGSNTNETITMPHAGVEDIVAIMIPEPKGKEIVSLLERNITVTMYI 192
Cdd:cd02122    71 CTFEEKIKLAAERNASAVVIYNNPGTGNETVKMSHPGTGDIVAIMITNPKGMEILELLERGISVTMVI 138

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
                  ....*....|....*....|....*.
gi 1907189878 288 DNCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16803     1 DHCAVCIEGYKQNDVVRILPCKHVFH 26

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
                  ....*....|....*....|....*
gi 1907189878 289 NCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16668     1 CCAVCIEPYKPSDVIRILPCKHIFH 25

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
                  ....*....|....*....|....*.
gi 1907189878 288 DNCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16802     1 DSCAVCIEPYKPNDVVRILTCNHLFH 26

PA_ScAPY_like: Protease-associated domain containing proteins like Saccharomyces cerevisiae aminopeptidase Y (ScAPY). This group contains various PA domain-containing proteins similar to the S. cerevisiae APY, including Trichophyton rubrum leucine aminopeptidase 1(LAP1). Proteins in this group belong to the peptidase M28 family. ScAPY hydrolyzes amino acid-4-methylcoumaryl-7-amides (MCAs). ScAPY more rapidly hydrolyzes dipeptidyl-MCAs. Hydrolysis of amino acid-MCAs or dipeptides is stimulated by Co2+ while the hydrolysis of dipeptidyl-MCAs, tripeptides, and longer peptides is inhibited by Co2+. ScAPY is vacuolar and is activated by proteolytic processing. LAP1 is a secreted leucine aminopeptidase. The significance of the PA domain to these proteins has not been ascertained. It may be a protein-protein interaction domain. At peptidase active sites, the PA domain may participate in substrate binding and/or promoting conformational changes, which influence the stability and accessibility of the site to substrate.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878  78 EHSPKQDARGEVVMASSaqdrLACDPnTKFaaPAHGKHWIALIPKGNCTYRDKIRNAFLQNASAVVIFN-----VGSNTN 152
Cdd:cd02130    15 TYSPAGEVTGPLVVVPN----LGCDA-ADY--PASVAGNIALIERGECPFGDKSALAGAAGAAAAIIYNnvpagGLSGTL 87

                          90       100       110
                  ....*....|....*....|....*....|....*..
gi 1907189878 153 ETITMPHAGVedivaIMIPEPKGKEIVSLLERNITVT 189
Cdd:cd02130    88 GEPSGPYVPT-----VGISQEDGKALVAALANGGEVS 119

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
                  ....*....|....*....|....*
gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFHS 314
Cdd:cd16454     2 CAICLEEFKEGEKVRVLPCNHLFHK 26

PA_C5a_like: Protease-associated domain containing proteins like Streptococcus pyogenes C5a peptidase. This group contains various PA domain-containing proteins similar to S. pyogenes C5a, including, i) Vpr, a minor extracellular serine protease from Bacillus subtilis, ii) a large molecular mass collagenolytic protease from Geobacillus collagenovorans MO-1, and iii) PrtS, a cell envelope protease from Streptococcus thermophilus CNRZ 385. Proteins in this group belong to the peptidase S8 family. C5a peptidase is a cell surface serine protease which specifically inactivates C5a [a chemotactic peptide, which attracts polymorphonuclear leukocytes (PMNs)], by cleaving it to release a 7-residue carboxy-terminal fragment which contains the PMN binding site. The significance of the PA domain to these proteins has not been ascertained. It may be a protein-protein interaction domain. At peptidase active sites, the PA domain may participate in substrate binding and/or promoting conformational changes, which influence the stability and accessibility of the site to substrate.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1907189878 113 GKhwIALIPKGNCTYRDKIRNAFLQNASAVVIFNvgsNTNETITMPHAGVEDIVAIMIPEPKGKEIVSLLERNITVT 189
Cdd:cd02133    48 GK--IALIQRGEITFVEKIANAKAAGAVGVIIYN---NVDGLIPGTLGEAVFIPVVFISKEDGEALKAALESSKKLT 119

RING-like zinc finger;

                          10        20
                  ....*....|....*....|....*
gi 1907189878 289 NCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:pfam17123   1 ECSICLDEFKPGQALFVLPCSHVFH 25

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
                  ....*....|....*....|....*...
gi 1907189878 286 DFDNCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16473     3 ECEECAICLENYQNGDLLRGLPCGHVFH 30

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
                  ....*....|....*....|....*.
gi 1907189878 289 NCAVCIEGYKPNDVVRILPCRHLFHS 314
Cdd:cd16667     1 ECAVCKEDFEVGEEVRQLPCKHLFHP 26

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
                  ....*....|....*....|....*
gi 1907189878 289 NCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16468     1 ECVICMADFVVGDPIRYLPCMHIYH 25

RING finger, H2 subclass, found in RING finger protein 215 (RNF215) and similar proteins; This family includes uncharacterized protein RNF215 and similar proteins. Although its biological function remains unclear, RNF215 shares high sequence similarity with PA-TM-RING ubiquitin ligases, which have 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.

                          10        20
                  ....*....|....*....|....*.
gi 1907189878 288 DNCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16670     1 ESCAVCLDQFYKNQCLRVLPCLHEFH 26

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
                  ....*....|....*....|....*....|....*.
gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFH-----SWGQLQK 320
Cdd:cd16675     3 CAVCLEEFKPKDELGICPCKHAFHrkcliKWLEVRK 38

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
                  ....*....|....*....|....
gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16448     1 CVICLEEFEEGDVVRLLPCGHVFH 24

Ring finger domain;

                          10        20
                  ....*....|....*....|....*.
gi 1907189878 288 DNCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:pfam13639   1 DECPICLEEFEEGDKVVVLPCGHHFH 26

RING finger, H2 subclass, found in RING finger protein 122 (RNF122) and similar proteins; 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. It interacts with calcium-modulating cyclophilin ligand (CAML), which is not a substrate, but a stabilizer of RNF122. RNF122 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                          10        20
                  ....*....|....*....|....
gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16676     3 CAVCLEDFKTKDELGVLPCQHAFH 26

RING finger, H2 subclass, found in RING finger protein 126 (RNF126) 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). Moreover, 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. In addition, RNF126 and the related protein, RNF115 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. RNF126 contains an N-terminal BCA2 Zinc-finger domain (BZF), the AKT-phosphorylation sites, and the C-terminal C3H2C3-type RING-H2 finger.

                          10        20
                  ....*....|....*....|....*
gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFHS 314
Cdd:cd16801     2 CPVCKEDYTVGENVRQLPCNHLFHN 26

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878 117 IALIPKGNCTYRDKIRNAFLQNASAVVifnVGSNTNETITMPHAgvedIVAIMIPEPKGKEIVSL-LERNITVTMYITIG 195
Cdd:COG5540   149 DRCNRRGNETEEDPTRERRRTRFKGVI---RGSERNGETFRLHY----MVAPDKVDPRSEGVEDPvTLTTSINVTWDGLG 221

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1907189878 196 TRN---LQKYVSRTSVVFVSISFIVLMIISLAWLVFY---YIQRFR---YANARDRN---QYTIATGQDWQLYRRRL--- 260
Cdd:COG5540   222 NTYqapSQSAEAQDETGDMFWPRLSRFVGSRGFRVVFpriPSQELRflfLTQSKGSRfniILEIQINFDVGFYSSSEaip 301

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1907189878 261 GDAAKKAISKLQVRTIRKGDKETEsdfdnCAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:COG5540   302 TTTTKGSLKPLSIERAVEADKGVE-----CAICMSNFIKNDRLRVLPCDHRFH 349

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.

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gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFH 313
Cdd:cd16486     2 CRICLKAFQLGQHVRTLPCRHKFH 25

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.

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gi 1907189878 290 CAVCIEGYKPNDVVRILP-CRHLFH 313
Cdd:cd16461     2 CAICLSDYENGEELRRLPeCKHAFH 26

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.

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gi 1907189878 290 CAVCIEGYKPNDVVRILPCRHLFHS 314
Cdd:cd16467     2 CTICLGEYETGEKLRRLPCSHEFHS 26

PA_GO-like: Protease-associated domain containing proteins like Arabidopsis thaliana growth-on protein GRO10. This group contains various PA domain-containing proteins similar to the functionally uncharacterized Arabidopsis GRO10. The PA domain may be a protein-protein interaction domain. At peptidase active sites, the PA domain may participate in substrate binding and/or promoting conformational changes, which influence the stability and accessibility of the site to substrate.

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gi 1907189878 117 IALIPKGNCTYRDKIRNAFLQNASAVVIFNVGSNTNETITMPHAGVED--IVAIMIPEPKGKEIVSLLERNITV 188
Cdd:cd02132    62 IALVERGECAFTEKAKIAEAGGASALLIINDQEELYKMVCEDNDTSLNisIPVVMIPQSAGDALNKSLDQGKKV 135