RING finger, H2 subclass, found in RING finger proteins RNF121, RNF175 and similar proteins; This subfamily includes RNF121, RNF175 and similar proteins. RNF121 is an E3-ubiquitin ligase present in the endoplasmic reticulum (ER) and cis-Golgi compartments. It is a novel regulator of apoptosis. It also facilitates the degradation and membrane localization of voltage-gated sodium (NaV) channels, and thus plays a role in the quality control of NaV channels during their synthesis and subsequent transport to the membrane. Moreover, RNF121 acts as a broad regulator of nuclear factor kappaB (NF-kappaB) signaling since its silencing also dampens NF-kappaB activation following stimulation of toll-like receptors (TLRs), nod-like receptors (NLRs), RIG-I-like Receptors (RLRs) or after DNA damage. RNF121 contains five conserved transmembrane (TM) domains and a C3H2C2-type RING-H2 finger. RNF175 is an uncharacterized RING finger protein that shows high sequence similarity with RNF121. This family also includes Arabidopsis RING finger E3 ligase RHA2A, RHA2B, and their homologs. RHA2A is a positive regulator of abscisic acid (ABA) signaling during seed germination and early seedling development. RHA2B may play a role in the ubiquitin-dependent proteolysis pathway that respond to proteasome inhibition. All subfamily members contain a C3H2C3-type RING-H2 finger, which is responsible for E3-ubiquitin ligase activity.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 201 SVCAVCGQQIFVDVNEEGIIENTYRLSCNHVFHEFCIRGWCIVGKKQTCPYCKEK 255
Cdd:cd16475     1 NVCAVCGQKLDVDDNEEGIIEKTYKLSCNHVFHEFCIRGWCIVGKKQTCPYCKEK 55

RING finger, H2 subclass, found in RING finger proteins RNF121, RNF175 and similar proteins; This subfamily includes RNF121, RNF175 and similar proteins. RNF121 is an E3-ubiquitin ligase present in the endoplasmic reticulum (ER) and cis-Golgi compartments. It is a novel regulator of apoptosis. It also facilitates the degradation and membrane localization of voltage-gated sodium (NaV) channels, and thus plays a role in the quality control of NaV channels during their synthesis and subsequent transport to the membrane. Moreover, RNF121 acts as a broad regulator of nuclear factor kappaB (NF-kappaB) signaling since its silencing also dampens NF-kappaB activation following stimulation of toll-like receptors (TLRs), nod-like receptors (NLRs), RIG-I-like Receptors (RLRs) or after DNA damage. RNF121 contains five conserved transmembrane (TM) domains and a C3H2C2-type RING-H2 finger. RNF175 is an uncharacterized RING finger protein that shows high sequence similarity with RNF121. This family also includes Arabidopsis RING finger E3 ligase RHA2A, RHA2B, and their homologs. RHA2A is a positive regulator of abscisic acid (ABA) signaling during seed germination and early seedling development. RHA2B may play a role in the ubiquitin-dependent proteolysis pathway that respond to proteasome inhibition. All subfamily members contain a C3H2C3-type RING-H2 finger, which is responsible for E3-ubiquitin ligase activity.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 201 SVCAVCGQQIFVDVNEEGIIENTYRLSCNHVFHEFCIRGWCIVGKKQTCPYCKEK 255
Cdd:cd16475     1 NVCAVCGQKLDVDDNEEGIIEKTYKLSCNHVFHEFCIRGWCIVGKKQTCPYCKEK 55

Ring finger domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1720424424 203 CAVCGQQIFVDvneegiiENTYRLSCNHVFHEFCIRGWCivGKKQTCPYCK 253
Cdd:pfam13639   3 CPICLEEFEEG-------DKVVVLPCGHHFHRECLDKWL--RSSNTCPLCR 44

RING finger, H2 subclass, found in RING finger proteins RNF121, RNF175 and similar proteins; This subfamily includes RNF121, RNF175 and similar proteins. RNF121 is an E3-ubiquitin ligase present in the endoplasmic reticulum (ER) and cis-Golgi compartments. It is a novel regulator of apoptosis. It also facilitates the degradation and membrane localization of voltage-gated sodium (NaV) channels, and thus plays a role in the quality control of NaV channels during their synthesis and subsequent transport to the membrane. Moreover, RNF121 acts as a broad regulator of nuclear factor kappaB (NF-kappaB) signaling since its silencing also dampens NF-kappaB activation following stimulation of toll-like receptors (TLRs), nod-like receptors (NLRs), RIG-I-like Receptors (RLRs) or after DNA damage. RNF121 contains five conserved transmembrane (TM) domains and a C3H2C2-type RING-H2 finger. RNF175 is an uncharacterized RING finger protein that shows high sequence similarity with RNF121. This family also includes Arabidopsis RING finger E3 ligase RHA2A, RHA2B, and their homologs. RHA2A is a positive regulator of abscisic acid (ABA) signaling during seed germination and early seedling development. RHA2B may play a role in the ubiquitin-dependent proteolysis pathway that respond to proteasome inhibition. All subfamily members contain a C3H2C3-type RING-H2 finger, which is responsible for E3-ubiquitin ligase activity.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 201 SVCAVCGQQIFVDVNEEGIIENTYRLSCNHVFHEFCIRGWCIVGKKQTCPYCKEK 255
Cdd:cd16475     1 NVCAVCGQKLDVDDNEEGIIEKTYKLSCNHVFHEFCIRGWCIVGKKQTCPYCKEK 55

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1720424424 199 SDSVCAVCgqqifVDVNEEGiiENTYRLSCNHVFHEFCIRGWCIVGKKqtCPYCKEKVD 257
Cdd:cd16681     9 TEEKCTIC-----LSILEEG--EDVRRLPCMHLFHQVCVDQWLITNKK--CPICRVDIE 58

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        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1720424424 202 VCAVCgqqiFVDVNEEgiiENTYRLSCNHVFHEFCIRGWciVGKKQTCPYCK 253
Cdd:cd16454     1 TCAIC----LEEFKEG---EKVRVLPCNHLFHKDCIDPW--LEQHNTCPLCR 43

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 202 VCAVCgqqifVDVNEEGiiENTYRLSCNHVFHEFCIRGWcIVGKKQTCPYCKEKV 256
Cdd:cd16796    10 VCAIC-----LDEYEEG--DKLRILPCSHAYHCKCVDPW-LTKTKKTCPVCKQKV 56

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        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1720424424 202 VCAVCgqqifVDVNEEGiiENTYRLSCNHVFHEFCIRGWcIVGKKQTCPYCKE 254
Cdd:cd16797     2 VCAIC-----LDEYEEG--DKLRVLPCSHAYHSKCVDPW-LTQTKKTCPVCKQ 46

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 199 SDSVCAVCgqqifVDVNEEGiiENTYRLSCNHVFHEFCIRGWCIVGKKqtCPYCkeKVDLKRMFS 263
Cdd:cd16682     6 TDEKCTIC-----LSMLEDG--EDVRRLPCMHLFHQLCVDQWLAMSKK--CPIC--RVDIETQLG 59

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        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1720424424 203 CAVCGQqifvdvnEEGIIENTYRLSCNHVFHEFCIRGWciVGKKQTCPYCKE 254
Cdd:cd16801     2 CPVCKE-------DYTVGENVRQLPCNHLFHNDCIVPW--LEQHDTCPVCRK 44

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720424424 197 HLSDSVCAVCGQQIFVDVNEEGiientyrLSCNHVFHEFCIRGWcIVGKKQTCPYCKEKV 256
Cdd:cd16473     1 MLECEECAICLENYQNGDLLRG-------LPCGHVFHQNCIDVW-LERDNHCCPVCRWPV 52

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

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|
gi 1720424424  203 CAVCgqqifvdvnEEGIIENTYRLSCNHVFHEFCIRGWcIVGKKQTCPYC 252
Cdd:smart00184   1 CPIC---------LEEYLKDPVILPCGHTFCRSCIRKW-LESGNNTCPIC 40

RING finger, H2 subclass, found in RING finger protein 214 (RNF214) and similar proteins; RNF214 is an uncharacterized RING finger protein containing a C3H2C3-type RING-H2 finger, suggesting it may have E3-ubiquitin ligase activity.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1720424424 202 VCAVCgqQIFVDVNEegiienTYRLSCNHVFHEFCIRGWCIVGKKQTCPYC 252
Cdd:cd16477     2 LCLMC--QKLVQPSD------LHPMSCSHTVHKECIKFWAQSNKNNTCPFC 44

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
                  ....*....|....*....|....*....|....*.
gi 1720424424 221 ENTYRLSCNHVFHEFCIRGWciVGKKQTCPYCKEKV 256
Cdd:cd16481    12 DQLAKLECGHIFHKECIKQW--LKEQSTCPTCRVHV 45

RING finger, H2 subclass, found in RING finger protein 43 (RNF43) and similar proteins; RNF43 is a transmembrane E3 ubiquitin-protein ligase that plays an important role in frizzled (FZD)-dependent regulation of the Wnt/beta-catenin pathway. It functions as a tumor suppressor that inhibits Wnt/beta-catenin signaling by ubiquitinating FZD receptor and targeting it to the lysosomal pathway for degradation. miR-550a-5p directly targeted the 3'-UTR of gene RNF43 and regulated its expression. Moreover, RNF43 interacts with NEDD-4-like ubiquitin-protein ligase-1 (NEDL1) and regulates p53-mediated transcription. It may also be involved in cell growth control through the interaction with HAP95, a chromatin-associated protein interfacing the nuclear envelope. Mutations of RNF43 have been identified in various tumors, including colorectal cancer (CRC), endometrial cancer, mucinous ovarian tumors, gastric adenocarcinoma, pancreatic ductal adenocarcinoma, liver fluke-associated cholangiocarcinoma, hepatocellular carcinoma, and glioma. RNF43 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C3H2C3-type RING-H2 finger followed by a long C-terminal region.

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                  ....*....|....*....|....*....|....*....|....*....|....
gi 1720424424 199 SDSVCAVCGQQiFVDVNEEGIIentyrlSCNHVFHEFCIRGWCIvgKKQTCPYC 252
Cdd:cd16798     2 SAPVCAICLEE-FSEGQELRII------SCSHEFHRECVDPWLH--QHRTCPLC 46

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.

                          10        20        30
                  ....*....|....*....|....*....|
gi 1720424424 226 LSCNHVFHEFCIRGW--CIVGKKQTCPYCK 253
Cdd:cd16471    17 LSCSHVFHEACLSAFekFIESKNQKCPLCR 46

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        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1720424424 203 CAVCgqqiFVDVNEEgiiENTYRLSCNHVFHEFCIRGWciVGKKQTCPYCK 253
Cdd:cd16669     2 CPIC----LLEFEEG---ETVKQLPCKHSFHSDCILPW--LGKTNSCPLCR 43

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.

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                  ....*....|....*....|....*....|....*....|....*....|..
gi 1720424424 203 CAVCGQQIfvDVNEEGIIEntyrLSCNHVFHEFCIRGWCivgkKQTCPYCKE 254
Cdd:cd16457     3 CPVCLERM--DESVSGILT----ILCNHSFHCSCLSKWG----DSSCPVCRY 44

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.

                          10        20
                  ....*....|....*....|....*..
gi 1720424424 226 LSCNHVFHEFCIRGWcIVGKKQTCPYC 252
Cdd:cd00162    17 LSCGHTFSRSAIARW-LEGSKQKCPFC 42

RING finger, HC subclass, found in bifunctional apoptosis regulator (BAR); BAR, also known as RING finger protein 47, was originally identified as an inhibitor of Bax-induced apoptosis. It participates in the block of apoptosis induced by TNF-family death receptors (extrinsic pathway) and mitochondria-dependent apoptosis (intrinsic pathway). BAR is predominantly expressed by neurons in the central nervous system and is involved in the regulation of neuronal survival. It is an endoplasmic reticulum (ER)-associated RING-type E3 ubiquitin ligase that interacts with BI-1 protein and post-translationally regulates its stability, as well as functioning in ER stress. BAR contains an N-terminal C3HC4-type RING-HC finger, a SAM domain, a coiled-coil domain, and a C-terminal transmembrane (TM) domain. This model corresponds to the RING-HC finger responsible for the binding of ubiquitin conjugating enzymes (E2s).

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 1720424424 218 GIIENTYRLSCNHVFHEFCIRGWCIVGKKQTCPYCKEKV 256
Cdd:cd16497     9 DLLVNPTTLNCGHSFCRHCLALWWKSSKKTECPECRQKW 47

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        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1720424424 202 VCAVCgqqiFVDVNEEGIIentyrlSCNHVFHEFCIRGWCIVgkKQTCPYC 252
Cdd:cd16476     2 VCAIC----YQEMKEARIT------PCNHFFHGLCLRKWLYV--QDTCPLC 40

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        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1720424424 203 CAVCgqqifvdVNEEGIIENTYRLSCNHVFHEFCIRGWCIvgKKQTCPYCK 253
Cdd:cd16465     2 CPIC-------CSEYVKDEIATELPCHHLFHKPCITAWLQ--KSGTCPVCR 43

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

                          10        20
                  ....*....|....*....|....*...
gi 1720424424 226 LSCNHVFHEFCIRGWCIvgKKQTCPYCK 253
Cdd:cd23118    19 LPCQHQFHSECVDQWLR--RNPKCPVCR 44

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 1720424424 216 EEGiiENTYRLSCNHVFHEFCIRGWCIVGKkqTCPYCKEKVD 257
Cdd:cd23115    15 EEG--EDLLTLPCKHCYHSECIQQWLQINK--VCPVCSAEVT 52

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        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 203 CAVCGQQIFVDvneegiiENTYRLSCNHVFHEFCIRGWciVGKKQTCPYCKEKVD 257
Cdd:cd16800     3 CPVCKEDYTVG-------EQVRQLPCNHFFHSDCIVPW--LELHDTCPVCRKSLN 48

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
                  ....*....|....*....|....*...
gi 1720424424 226 LSCNHVFHEFCIRGWCIVGKKQTCPYCK 253
Cdd:cd16677    17 LSCSHVFHRACLESFERFSGKKTCPMCR 44

RING finger, H2 subclass, found in vacuolar protein sorting-associated proteins Vps8, Vps11, Vps18, Vps41, and similar proteins; This subfamily corresponds to a group of vacuolar protein sorting-associated proteins containing a C-terminal C3H2C3-type RING-H2 finger, which includes Vps8, Vps11, Vps18, and Vps41. Vps11 and Vps18 associate with Vps16 and Vps33 to form a Class C Vps core complex that is required for soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE)-mediated membrane fusion at the lysosome-like yeast vacuole. The core complex, together with two additional compartment-specific subunits, forms the tethering complexes HOPS (homotypic vacuole fusion and protein sorting) and CORVET (class C core vacuole/endosome transport). CORVET contains the additional Vps3 and Vps8 subunits. It operates at endosomes, controls traffic into late endosomes and interacts with the Rab5/Vps21-GTP form. HOPS contains the additional Vps39 and Vps41 subunits. It operates at the lysosomal vacuole, controls all traffic from late endosomes into the vacuole and interacts with the Rab7/Ypt7-GTP form.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1720424424 202 VCAVCGQQIFVDVN--EEGIIEntyrLSCNHVFHEFCIRGwcIVGKKQTCPYC 252
Cdd:cd16484     1 KCPICTLPLKESDVgaNSPVVV----FFCGHMFHKFCLPE--LSMTEAACPIC 47

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

                          10        20        30
                  ....*....|....*....|....*....|...
gi 1720424424 221 ENTYRLSCNHVFHEFCIRGWcIVGKKQTCPYCK 253
Cdd:cd23123    14 EEVKKLDCRHKFHKQCIEGW-LKHLNFNCPLCR 45

RING finger, H2 subclass, found in Arabidopsis thaliana protein WAV3 homolog 2 (WAVH2) and similar proteins; WAVH2, also known as RING-type E3 ubiquitin transferase WAVH2, is a probable E3 ubiquitin-protein ligase involved in the regulation of root growth. It acts as a positive regulator of root gravitropism. WAVH2 contains a C3H2C3-type RING-H2 finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1720424424 198 LSDSVCAVCgqqifVDVNEEGIIENTYRLSCNHVFHEFCIRGWcIVGKKQTCPYCKEK 255
Cdd:cd23114     2 ASSSECSIC-----LETMKPGSGHAIFTAECSHSFHFECIAGN-VRHGNLRCPVCRAK 53

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        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1720424424 203 CAVCGqqifvdvneEGIIENTYRLSCNHVFHEFCIRGWcIVGKKQTCPYC 252
Cdd:pfam00097   1 CPICL---------EEPKDPVTLLPCGHLFCSKCIRSW-LESGNVTCPLC 40

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720424424 202 VCAVCGQQiFVDVNEEGIIentyrlSCNHVFHEFCIRGWCIVgkKQTCPYCKEKV 256
Cdd:cd16675     2 ICAVCLEE-FKPKDELGIC------PCKHAFHRKCLIKWLEV--RKVCPLCNMPV 47

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1720424424 203 CAVCGQqifvdvneegIIENTYRLSCNHVFHEFCIRGwCIVGKKQTCPYCKEKV 256
Cdd:cd16542     4 CAVCLE----------VLHQPVRTRCGHVFCRPCIAT-SLRNNTWTCPYCRAYL 46