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        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 273 DNSSECVVCLSDLRDTLILPCRHlCLCTSCADTLRYQANNCPICRLPFR----------------------ALLQIRAVR 330
Cdd:TIGR00599  24 DTSLRCHICKDFFDVPVLTSCSH-TFCSLCIRRCLSNQPKCPLCRAEDQesklrsnwlvseivesfknlrpSLLEFLRIP 102

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 331 KKPGALSPISFSPVLAQSVDHDEHSSSDSIPPgyEPISLLEALNGLRAVSPAIPSAPLYEEITYSGIS----------DG 400
Cdd:TIGR00599 103 KTTPVENPDLAGPENSSKIELIEESESDGVDA--EDEDLQRSATSSRALAARSTADILQLSSDPSKRNdadyrseppnEG 180

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 401 LSQasCPLAGlDRIMESGLQKgktqsKSPDSTLRSPSFPIHEEDEEKlSEDSDAPLPPSGVELVLRESSSPESFGTEEGD 480
Cdd:TIGR00599 181 LVQ--CPICQ-QRMPEKAVER-----HLDSECLGSPSLGASTTFPTE-SNPHNKSSSRFSFRTVDKSSTGETSHVDKYLN 251

                         250
                  ....*....|...
gi 1264232225 481 EPSLKQGSRVPSI 493
Cdd:TIGR00599 252 SMMSKPPERLPKI 264

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCADTLRYQANNCPICRLP 319
Cdd:pfam13920   4 LCVICLDRPRNVVLLPCGHLCLCEECAERLLRKKKKCPICRQP 46

N1R/p28-like protein; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 232 FSVKPLKQKQIVDRVSYL--LQE---IYGIENKNNQETK------PS------DDENSDNSSECVVCLSDLRDTL----- 289
Cdd:PHA02929  114 YNQKILKNKPSNDKINYIymRKEedmFYAIINKKGKNYKkflktiPSvlseyeKLYNRSKDKECAICMEKVYDKEiknmy 193

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*
gi 1264232225 290 --ILP-CRHLcLCTSCADTLRYQANNCPICRLPFRALLQIRAVRK 331
Cdd:PHA02929  194 fgILSnCNHV-FCIECIDIWKKEKNTCPVCRTPFISVIKSRFFTK 237

Uncharacterized conserved protein, contains RING Zn-finger [General function prediction only];

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1264232225 259 KNNQETKP-----SDDENSDNSSECVVCLSDLRDTLILPCRHLcLCTSCADTLR--YQANNCPICR 317
Cdd:COG5236    40 KNNLSAEPnlttsSADDTDEENMNCQICAGSTTYSARYPCGHQ-ICHACAVRLRalYMQKGCPLCR 104

Modified RING finger, HC subclass (C3HC5-type), found in RING finger protein 157 (RNF157) and similar proteins; RNF157 is a cytoplasmic E3 ubiquitin ligase predominantly expressed in brain. It is a homolog of the E3 ligase mahogunin ring finger-1 (MGRN1). In cultured neurons, it promotes neuronal survival in an E3 ligase-dependent manner. In contrast, it supports growth and maintenance of dendrites independent of its E3 ligase activity. RNF157 interacts with and ubiquitinates the adaptor protein APBB1 (amyloid beta precursor protein-binding, family B, member 1 or Fe65), which regulates neuronal survival, but not dendritic growth downstream of RNF157. The nuclear localization of APBB1 together with its interaction partner RNA-binding protein SART3 (squamous cell carcinoma antigen recognized by T cells 3 or Tip110) is crucial to trigger apoptosis. RNF157 contains a modified C3HC5-type RING-HC finger, and a functionally uncharacterized region, known as domain associated with RING2 (DAR2), N-terminal to the RING finger. The C3HC5-type RING-HC finger is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 272 SDNSSECVVCLSDLRDTLILPCRHLCLCTSCADTLRYQANNCPICRLPFRALLQIRAVRK 331
Cdd:cd16817     1 SDNSAECVVCLSDVRDTLILPCRHLCLCNACADTLRYQANNCPICRLPFRALLQIRAMRK 60

Modified RING finger, HC subclass (C3HC5-type), found in RING finger proteins, RNF26, RNF197 (CGRRF1), RNF156 (MGRN1), RNF157 and similar proteins; This subfamily corresponds to a group of RING finger proteins containing a modified C3HC5-type RING-HC finger, which is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain. Cell growth regulator with RING finger domain protein 1 (CGRRF1), also known as cell growth regulatory gene 19 protein (CGR19) or RING finger protein 197 (RNF197), functions as a novel biomarker to monitor endometrial sensitivity and response to insulin-sensitizing drugs, such as metformin, in the context of obesity. RNF26 is an E3 ubiquitin ligase that temporally regulates virus-triggered type I interferon induction by increasing the stability of Mediator of IRF3 activation, MITA, also known as STING, through K11-linked polyubiquitination after viral infection and promoting degradation of IRF3, another important component required for virus-triggered interferon induction. Mahogunin ring finger-1 (MGRN1), also known as RING finger protein 156 (RNF156), is a cytosolic E3 ubiquitin-protein ligase that inhibits signaling through the G protein-coupled melanocortin receptors-1 (MC1R), -2 (MC2R) and -4 (MC4R) via ubiquitylation-dependent and -independent processes. It suppresses chaperone-associated misfolded protein aggregation and toxicity. RNF157 is a cytoplasmic E3 ubiquitin ligase predominantly expressed in the brain. It is a homolog of the E3 ligase MGRN1. In cultured neurons, it promotes neuronal survival in an E3 ligase-dependent manner. In contrast, it supports growth and maintenance of dendrites independent of its E3 ligase activity. RNF157 interacts with and ubiquitinates the adaptor protein APBB1 (amyloid beta precursor protein-binding, family B, member 1 or Fe65), which regulates neuronal survival, but not dendritic growth downstream of RNF157. The nuclear localization of APBB1 together with its interaction partner RNA-binding protein SART3 (squamous cell carcinoma antigen recognized by T cells 3 or Tip110) is crucial to trigger apoptosis.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1264232225 276 SECVVCLSDLRDTLILPCRHLCLCTSCADTLRYQanNCPICR 317
Cdd:cd16649     1 GLCVVCLENPASVLLLPCRHLCLCEVCAKGLRGK--TCPICR 40

Modified RING finger, HC subclass (C3HC5-type), found in RING finger protein 26 (RNF26) and similar proteins; RNF26 is an E3 ubiquitin ligase that temporally regulates virus-triggered type I interferon induction by increasing the stability of Mediator of IRF3 activation, MITA, also known as STING, through K11-linked polyubiquitination of MITA after viral infection, and promoting the degradation of IRF3, another important component required for virus-triggered interferon induction. Although RNF26 substrates of ubiquitination remain unclear at present, RNF26 upregulation in gastric cancer might be implicated in carcinogenesis through dysregulation of growth regulators. RNF26 contains an N-terminal leucine zipper domain and a C-terminal modified C3HC5-type RING-HC finger, which is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1264232225 278 CVVCLSDLRDTLILPCRHLCLCTSCADTLRYQA---NNCPICRLPFRALLQI 326
Cdd:cd16788     8 CVICQDQSKTVLILPCRHMCLCRQCANILLQQPvyrRNCPLCRTMILQTLDV 59

RING finger, HC subclass, found in Arabidopsis thaliana protein XB3 homolog 5 (XBAT35) and similar proteins; XBAT35, also known as ankyrin repeat domain and RING finger-containing protein XBAT35, or RING-type E3 ubiquitin transferase XBAT35, has no E3 ubiquitin-protein ligase activity observed when associated with the E2 enzyme UBC8 in vitro. It contains a typical C3HC4-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1264232225 274 NSSECVVCLSDLRDTLILPCRHLCLCTSCADTLRYQANNCPICRLPFRALLQI 326
Cdd:cd23129     1 QRDECVVCMDAPRDAVCVPCGHVAGCMSCLKALMQSSPLCPICRAPVRQVIKV 53

RING finger, HC subclass, found in Arabidopsis thaliana MND1-interacting protein 1 (MIP1) and similar proteins; This subfamily includes Arabidopsis thaliana MIP1, RING finger protein 4 (RF4) and RING finger protein 298 (RF298). MIP1 interacts with MND1, HOP2 and XRI1. RF4 and RF298 are putative E3 ubiquitin-protein ligase that may mediate E2-dependent protein ubiquitination. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCADTLRYQA-NNCPICR 317
Cdd:cd23128     5 ECVMCMEEERSVVFLPCAHQVVCSGCNDLHEKKGmRECPSCR 46

Modified RING finger, HC subclass (C3HC5-type), found in cell growth regulator with RING finger domain protein 1 (CGRRF1) and similar proteins; CGRRF1, also known as cell growth regulatory gene 19 protein (CGR19) or RING finger protein 197 (RNF197), functions as a novel biomarker to monitor endometrial sensitivity and response to insulin-sensitizing drugs, such as metformin, in the context of obesity. CGRRF1 contains a C-terminal modified C3HC5-type RING-HC finger, which is distinguished from typical C3HC4 RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCAdtlrYQANNCPICR 317
Cdd:cd16787     2 DCVVCQNAPVNRVLLPCRHACVCDECF----KRLQRCPMCR 38

Modified RING finger, HC subclass (C3HC5-type), found in mitochondrial-anchored protein ligase (MAPL) and similar proteins; MAPL, also known as MULAN, mitochondrial ubiquitin ligase activator of NFKB 1, E3 SUMO-protein ligase MUL1, E3 ubiquitin-protein ligase MUL1, growth inhibition and death E3 ligase (GIDE), putative NF-kappa-B-activating protein 266, or RING finger protein 218 (RNF218), is a multifunctional mitochondrial outer membrane protein involved in several processes specific to metazoan (multicellular animal) cells, such as NF-kappaB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. MAPL contains a unique BAM (beside a membrane)/GIDE (growth inhibition death E3 ligase) domain and a C-terminal modified cytosolic C3HC5-type RING-HC finger which is distinguished from typical C3HC4-type RING-HC finger due to the existence of the additional cysteine residue in the middle portion of the RING finger domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1264232225 273 DNSseCVVCLSDLRDTLILPCRHLCLCTSCADTLRyQANNCPICR 317
Cdd:cd16648     1 DNA--CVICLSNPRSCVFLECGHVCSCIECYEALP-SPKKCPICR 42

HC subclass of RING (RING-HC) finger 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 a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers 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 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 enables efficient transfer of ubiquitin from E2 to the substrates.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLClCTSCADTL-RYQANNCPIC 316
Cdd:cd16449     2 ECPICLERLKDPVLLPCGHVF-CRECIRRLlESGSIKCPIC 41

Modified RING finger, HC subclass (C2H2C4-type), found in E3 ubiquitin-protein ligase MDM2, protein MDM4 and similar proteins; MDM2 (also known as HDM2) and MDM4 (also known as MDMX or HDMX) are the primary p53 tumor suppressor negative regulators. They have non-redundant roles in the regulation of p53. MDM2 mainly functions to control p53 stability, while MDM4 controls p53 transcriptional activity. Both MDM2 and MDM4 contain an N-terminal p53-binding domain, a RanBP2-type zinc finger (zf-RanBP2) domain near the central acidic region, and a C-terminal modified C2H2C4-type RING-HC finger. Mdm2 can form homo-oligomers through its RING domain and displays E3 ubiquitin ligase activity that catalyzes the attachment of ubiquitin to p53 as an essential step in the regulation of its levels in cells. Despite its RING domain and structural similarity with MDM2, MDM4 does not homo-oligomerize and lacks ubiquitin-ligase function, but inhibits the transcriptional activity of p53. In addition, both their RING domains are responsible for the hetero-oligomerization, which is crucial for the suppression of P53 activity during embryonic development and the recruitment of E2 ubiquitin-conjugating enzymes. Moreover, MDM2 and MDM4 can be phosphorylated and destabilized in response to DNA damage stress. In response to ribosomal stress, MDM2-mediated p53 ubiquitination and degradation can be inhibited through the interaction with ribosomal proteins L5, L11, and L23. However, MDM4 is not bound to ribosomal proteins, suggesting its different response to regulation by small basic proteins such as ribosomal proteins and ARF.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1264232225 278 CVVCLSDLRDTLILPCR--HLCLCTSCADTLRYQANNCPICRLPFRALLQ 325
Cdd:cd16646     3 CVICLSRPRTAAIVHGKtgHQVACYTCAKKLKRRGKPCPVCRRPIQNVIK 52

RING finger, HC subclass, found in Dictyostelium discoideum Cbl-like protein A (CblA) and similar proteins; CblA is a Dictyostelium homolog of the Cbl proteins which are multi-domain proteins acting as key negative regulators of various receptor and non-receptor tyrosine kinase signaling. CblA upregulates STATc tyrosine phosphorylation by downregulating PTP3, the protein tyrosine phosphatase responsible for dephosphorylating STATc. STATc is a signal transducer and activator of transcription protein. Like other Cbl proteins, CblA contains a tyrosine-kinase-binding domain (TKB), a proline-rich domain, a C3HC4-type RING-HC finger, and an ubiquitin-associated (UBA) domain. TKB, also known as a phosphotyrosine binding PTB domain, is composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain. This family also includes Drosophila melanogaster defense repressor 1 (Dnr1) that was identified as an inhibitor of Dredd activity in the absence of a microbial insult in Drosophila S2 cells. It inhibits the Drosophila initiator caspases Dredd and Dronc. Moreover, Dnr1 acts as a negative regulator of the Imd (immune deficiency) innate immune-response pathway. Its mutations cause neurodegeneration in Drosophila by activating the innate immune response in the brain. Dnr1 contains a FERM N-terminal domain followed by a region rich in glutamine and serine residues, a central FERM domain, and a C-terminal C3HC4-type RING-HC finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1264232225 268 DDENSDnssECVVCLSDLRDTLILPCRHLCLCTSCADTLRyqanNCPICRLPFRALLQI 326
Cdd:cd16501     1 SGADAD---LCVVCMDAPIDTVFLECGHLACCRLCSKRLR----VCPICRQPISRVVRI 52

RING finger, HC subclass, found in apoptosis protein c-IAP1, c-IAP2, livin, and similar proteins; The cellular inhibitor of apoptosis protein c-IAPs function as ubiquitin E3 ligases that mediate the ubiquitination of substrates involved in apoptosis, nuclear factor-kappaB (NF-kappaB) signaling, and oncogenesis. Unlike other IAPs, such as XIAP, c-IAPs exhibit minimal binding to caspases and may not play an important role in the inhibition of these proteases. c-IAP1, also known as baculoviral IAP repeat-containing protein BIRC2, IAP-2, RING finger protein 48, or TNFR2-TRAF-signaling complex protein 2, is a potent regulator of the tumor necrosis factor (TNF) receptor family and NF-kappaB signaling pathways in the cytoplasm. It can also regulate E2F1 transcription factor-mediated control of cyclin transcription in the nucleus. c-IAP2, also known as BIRC3, IAP-1, apoptosis inhibitor 2 (API2), or IAP homolog C, also influences ubiquitin-dependent pathways that modulate innate immune signalling by activation of NF-kappaB. c-IAPs contain three N-terminal baculoviral IAP repeat (BIR) domains that enable interactions with proteins, a ubiquitin-association (UBA) domain that is responsible for the binding of polyubiquitin (polyUb), a caspase activation and recruitment domain (CARD) that serves as a protein interaction surface, and a C3HC4-type RING-HC finger at the carboxyl terminus that is required for ubiquitin ligase activity. Livin, also known as baculoviral IAP repeat-containing protein 7 (BIRC7), kidney inhibitor of apoptosis protein (KIAP), melanoma inhibitor of apoptosis protein (ML-IAP), or RING finger protein 50, was identified as the melanoma IAP. It plays crucial roles in apoptosis, cell proliferation, and cell cycle control. Its anti-apoptotic activity is regulated by the inhibition of caspase-3, -7, and -9. Its E3 ubiquitin-ligase-like activity promotes degradation of Smac/DIABLO, a critical endogenous regulator of all IAPs. Unlike other family members, mammalian livin contains a single BIR domain and a C3HC4-type RING-HC finger. The UBA domain can be detected in non-mammalian homologs of livin.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1264232225 278 CVVCLSDLRDTLILPCRHLCLCTSCADTLRyqanNCPICRLPFR 321
Cdd:cd16713    10 CKVCMDKEVSIVFIPCGHLVVCTECAPSLR----KCPICRATIK 49

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 1264232225  278 CVVCLSD-LRDTLILPCRHLcLCTSCADT-LRYQANNCPIC 316
Cdd:smart00184   1 CPICLEEyLKDPVILPCGHT-FCRSCIRKwLESGNNTCPIC 40

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1264232225 269 DENSDNSSECVVCLS---DLRDTLILPCRHLcLCTSCADTLRYQANNCPICRLPFRALL 324
Cdd:cd16682     1 GEESDTDEKCTICLSmleDGEDVRRLPCMHL-FHQLCVDQWLAMSKKCPICRVDIETQL 58

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 1264232225 277 ECVVCLS--DLRDTL-ILPCRHlCLCTSCADT-LRYQANNCPICRLPF 320
Cdd:cd16486     1 QCRICLKafQLGQHVrTLPCRH-KFHRDCIDNwLLHSRNSCPIDGQVV 47

Modified RING finger, HC subclass (C4C4-type), found in Saccharomyces cerevisiae amino acid sensor-independent protein Asi1p, Asi3p and similar proteins; Asi1p and Asi3p are inner nuclear membrane proteins that act as negative regulators of SPS (Ssy1-Ptr3-Ssy5)-sensor signaling in yeast. Together with Asi2p, they assemble into an Asi complex that functions in the SPS amino acid sensing pathway involved in degradation of Stp1 and Stp2 transcription factors. Both Asi1p and Asi3p contain five membrane-spanning domains, as well as highly conserved RING fingers at their extreme C termini, which are C4C4-type RING finger motifs whose overall folding is similar to that of the C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 278 CVVCLSDLRDTLILPCRHLCLCTSCADTLRYQA-NNCPICR 317
Cdd:cd16616     4 CVICKSNPRNIVLWPCRCLALCDDCRLSLAMRGfHTCVCCR 44

RING finger, HC subclass, found in zinc finger protein 598 (ZNF598) and similar proteins; ZNF598 associates with eukaryotic initiation factor 4E (eIF4E) homologous protein from mammals (m4EHP) by binding to Grb10-interacting GYF protein 2 (GIGYF2). The m4EHP-GIGYF2 complex functions as a translational repressor and is essential for normal embryonic development of mammalian. ZNF598 harbors a C3HC4-type RING-HC finger at its N-terminus.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLClCTSCADTLR--YQANNCPICR 317
Cdd:cd16615     2 TCVICCEEIEYFAVGPCNHPV-CYKCSLRMRvlYKDKYCPICR 43

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1264232225 274 NSSECVVCLSDLRDTLILPCRHLcLCTSCADTLRYQANNCPICR 317
Cdd:cd16561     1 GEQECSICLEDLNDPVKLPCDHV-FCEECIRQWLPGQMSCPLCR 43

RING finger, HC subclass, found in tripartite motif-containing protein 62 (TRIM62) and similar proteins; TRIM62, also known as Ductal Epithelium Associated Ring Chromosome 1 (DEAR1), is a cytoplasmic E3 ubiquitin-protein ligase that was identified as a dominant regulator of acinar morphogenesis in the mammary gland. It is implicated in the inflammatory response of immune cells by regulating the Toll-like receptor 4 (TLR4) signaling pathway, leading to increased activity of the activator protein 1 (AP-1) transcription factor in primary macrophages. It is also involved in muscular protein homeostasis, especially during inflammation-induced atrophy, and may play a role in the pathogenesis of ICU-acquired weakness (ICUAW) by activating and maintaining inflammation in myocytes. Moreover, TRIM62 facilitates K27-linked poly-ubiquitination of CARD9 and also regulates CARD9-mediated anti-fungal immunity and intestinal inflammation. It also functions as a chromosome 1p35 tumor suppressor and negatively regulates transforming growth factor beta (TGFbeta)-driven epithelial-mesenchymal transition (EMT) by binding to and promoting the ubiquitination of SMAD3, a major effector of TGFbeta-mediated EMT. TRIM62 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
                  ....*....|....*....|....*....|....*....|....*
gi 1264232225 278 CVVCLSDLRDTLILPCRHLcLCTSCADT--LRYQANNCPICRLPF 320
Cdd:cd16608     9 CSICLSIYQDPVSLGCEHY-FCRQCITEhwSRSEHRDCPECRRTF 52

N1R/p28-like protein; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 232 FSVKPLKQKQIVDRVSYL--LQE---IYGIENKNNQETK------PS------DDENSDNSSECVVCLSDLRDTL----- 289
Cdd:PHA02929  114 YNQKILKNKPSNDKINYIymRKEedmFYAIINKKGKNYKkflktiPSvlseyeKLYNRSKDKECAICMEKVYDKEiknmy 193

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*
gi 1264232225 290 --ILP-CRHLcLCTSCADTLRYQANNCPICRLPFRALLQIRAVRK 331
Cdd:PHA02929  194 fgILSnCNHV-FCIECIDIWKKEKNTCPVCRTPFISVIKSRFFTK 237

first RING finger, HC subclass, found in mind bomb 1 (MIB1) and similar proteins; MIB1, also known as DAPK-interacting protein 1 (DIP-1) or zinc finger ZZ type with ankyrin repeat domain protein 2, is a large, multi-domain E3 ubiquitin-protein ligase that promotes ubiquitination of the cytoplasmic tails of Notch ligands, and thus plays an essential role in controlling metazoan development by Notch signaling. It is also involved in Wnt/beta-catenin signaling and nuclear factor (NF)-kappaB signaling, and has been implicated in innate immunity, neuronal function, genomic stability, and cell death. MIB1 contains an MZM region with two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region consisting of three C3HC4-type RING-HC fingers. This model corresponds to the first RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCADTLRyqanNCPICR 317
Cdd:cd16724     2 ECMVCSDMKRDTLFGPCGHIATCSLCSPRVK----KCLICK 38

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 1264232225 277 ECVVCLSDLRD---TLILPCRHLCLCtSCADTLRYQANNCPICR 317
Cdd:cd16454     1 TCAICLEEFKEgekVRVLPCNHLFHK-DCIDPWLEQHNTCPLCR 43

RING finger, HC subclass, found in Schizosaccharomyces pombe DNA repair protein Rad8 (SpRad8) and similar proteins; SpRad8 is a conserved protein homologous to Saccharomyces cerevisiae DNA repair protein Rad5 and human helicase-like transcription factor (HLTF) that is required for error-free postreplication repair by contributing to polyubiquitylation of PCNA. SpRad8 contains a C3HC4-type RING-HC finger responsible for the E3 ubiquitin ligase activity, a SNF2-family helicase domain including an ATP binding site, and a family-specific HIRAN domain (HIP116, Rad5p N-terminal domain) that contributes to nuclear localization.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1264232225 272 SDNSSECVVCLSD-LRDTLILPCRHLClCTSC-ADTLRYQANN-----CPICRLPF 320
Cdd:cd16572     1 EDAENECPICAEEpISELALTRCWHSA-CKDClLDHIEFQKSKnevplCPTCRQPI 55

RING finger, HC subclass, found in mind bomb MIB1, MIB2, and similar proteins; MIBs are large, multi-domain E3 ubiquitin-protein ligases that promote ubiquitination of the cytoplasmic tails of Notch ligands. They are also responsible for TBK1 K63-linked ubiquitination and activation, promoting interferon production and controlling antiviral immunity. Moreover, MIBs selectively control responses to cytosolic RNA and regulate type I interferon transcription. Both MIB1 and MIB2 have similar domain architectures, which consist of two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region, where MIB1 and MIB2 contain three and two C3HC4-type RING-HC fingers, respectively. This model corresponds to the first RING-HC finger of MIB1 and MIB2, as well as the second RING-HC finger of MIB1.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCAdtlrYQANNCPICR 317
Cdd:cd16519     2 ECRVCSDKKALVLFQPCGHVVACEECS----LRMKKCLQCK 38

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1264232225 268 DDENSDNSSECVVCLSDLR---DTLILPCRHLcLCTSCADTLRYQANNCPICRLPFRALL 324
Cdd:cd16681     3 EGTEEDTEEKCTICLSILEegeDVRRLPCMHL-FHQVCVDQWLITNKKCPICRVDIEAQL 61

RING finger, HC subclass, found in caspases-8 and -10-associated RING finger protein 2 (CARP-2) and similar proteins; CARP-2, also known as rififylin, caspase regulator CARP2, FYVE-RING finger protein Sakura (Fring), RING finger and FYVE-like domain-containing protein 1, RING finger protein 189 (RNF189), or RING finger protein 34-like, is an endosome-associated E3 ubiquitin-protein ligase that targets internalized receptor interacting kinase (RIP) for proteasome-mediated degradation. It acts as a negative regulator of tumor necrosis factor (TNF)-induced nuclear factor (NF)-kappaB activation. It also regulates the p53 signaling pathway by degrading 14-3-3sigma and stabilizing MDM2. As a caspase regulator, CARP2 does not localize to membranes in the cell and is involved in the negative regulation of apoptosis, specifically targeting two initiator caspases, caspase 8 and caspase 10. CARP2 contains an N-terminal FYVE-like domain and a C-terminal C3HC4-type RING-HC finger domain.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1264232225 278 CVVCLSDLRDTLILPCRHLCLCTSCADTLryqaNNCPICR 317
Cdd:cd16707     5 CKICMDSPIDCVLLECGHMVTCTKCGKRM----SECPICR 40

RING finger, HC subclass, found in Casitas B-lineage lymphoma (Cbl) proteins; The Cbl adaptor protein family contains a small class of RING-type E3 ubiquitin ligases with oncogenic activity, which is represented by three mammalian members, c-Cbl, Cbl-b and Cbl-c, as well as two invertebrate Cbl-family proteins, D-Cbl in Drosophila and Sli-1 in C. elegans. Cbl proteins function as potent negative regulators of various signaling cascades in a wide range of cell types. They play roles in ubiquitinating activated tyrosine kinases and targeting them for degradation. D-Cbl associates with the Drosophila epidermal growth factor receptor (EGFR) and overexpression of D-Cbl in the eye of Drosophila embryos inhibits EGFR-dependent photoreceptor cell development. Sli-1 is a negative regulator of the Let-23 receptor tyrosine kinase, an EGFR homolog, in vulva development. Cbl proteins in this subfamily consist of a highly conserved N-terminal half that includes a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain) and a C3HC4-type RING-HC finger, both of which are required for Cbl-mediated downregulation of RTKs, and a divergent C-terminal region.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 278 CVVCLSDLRDTLILPCRHLcLCTSCADTLRYQ-ANNCPICR 317
Cdd:cd16502     4 CKICAENDKDVRIEPCGHL-LCTPCLTSWQDSdGQTCPFCR 43

RING finger, HC subclass, found in Arabidopsis thaliana BRCA1-associated RING domain protein 1 (AtBARD1) and similar proteins; AtBARD1, also called protein REPRESSOR OF WUSCHEL 1, binds specifically to H3K4me3 regions of target gene (e.g. WUS and WOX5) promoters to repress their transcription via chromatin remodeling. It is required for the shoot apical meristem (SAM) organization and maintenance, by confining WUS expression to the organizing center, and for the quiescent center (QC) development in the root apical meristem (RAM), by repressing WOX5 expression in the root proximal meristem. AtBARD1 plays a role in DNA repair and in cell-cycle control. It is required for the repair of DNA double-strand breaks (DSBs), both natural and induced by genotoxic stress, by homologous recombination (HR). AtBARD1 contains a typical C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1264232225 278 CVVCLSDLRDTLILPCRHLcLCTSCADTLRYQANNCPICRLPF 320
Cdd:cd23146     7 CPICLKLLNRPVLLPCDHI-FCSSCITDSTKVGSDCPVCKLPY 48

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
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1264232225 275 SSECVVCLSDLRDT---LILPCRHL----CLCtscaDTLRYQANNCPICRLP 319
Cdd:cd16473     4 CEECAICLENYQNGdllRGLPCGHVfhqnCID----VWLERDNHCCPVCRWP 51

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 2(RNFT2); RNFT2, also known as transmembrane protein 118 (TMEM118), is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1264232225 278 CVVCLSDLRDTLILPCRHLcLCTSCADTLRYQANNCPICR 317
Cdd:cd16742    16 CAICQAEFREPLILICQHV-FCEECLCLWFDRERTCPLCR 54

Modified RING finger, HC subclass (C2H2C4-type), found in E3 ubiquitin-protein ligase MDM2 and similar proteins; MDM2, also known as double minute 2 protein (Hdm2), oncoprotein MDM2, or p53-binding protein, exerts its oncogenic activity predominantly by binding p53 tumor suppressor and blocking its transcriptional activity. It forms homo-oligomers and displays E3 ubiquitin ligase activity that catalyzes the attachment of ubiquitin to p53 as an essential step in the regulation of its levels in cells. Moreover, in response to ribosomal stress, MDM2-mediated p53 ubiquitination and degradation can be inhibited through its interaction with ribosomal proteins L5, L11, and L23. MDM2 can be phosphorylated in the DNA damage. Meanwhile, MDM2 has a p53-independent role in tumorigenesis and cell growth regulation. In addition, it binds interferon (IFN) regulatory factor-2 (IRF-2), an IFN-regulated transcription factor, and mediates its ubiquitination. MDM2 contains an N-terminal p53-binding domain, and a C-terminal modified C2H2C4-type RING-HC finger conferring E3 ligase activity that is required for ubiquitination and nuclear export of p53. It is also responsible for the hetero-oligomerization of MDM2, which is crucial for the suppression of P53 activity during embryonic development, and the recruitment of E2 ubiquitin-conjugating enzymes. MDM2 also harbors a RanBP2-type zinc finger (zf-RanBP2) domain, as well as a nuclear localization signal (NLS) and a nuclear export signal (NES), near the central acidic region. The zf-RanBP2 domain plays an important role in mediating MDM2 binding to ribosomal proteins and thus is involved in MDM2-mediated p53 suppression.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1264232225 278 CVVCLSDLRDTLILPCR--HLCLCTSCADTLRYQANNCPICRLPFRALL 324
Cdd:cd16783     4 CVICQTRPKNGCIVHGKtgHLMACFTCAKKLKKRNKPCPVCRQPIQMIV 52

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

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                  ....*....|....*....|....*....|....*....|....*
gi 1264232225 278 CVVCLSDLRDTLILPCRHlCLCTSCADTlRYQANN--CPICRLPF 320
Cdd:cd16499     9 CSVCNDRFKDVIITKCGH-VFCNECVQK-RLETRQrkCPGCGKAF 51

RING finger, HC subclass, found in tripartite motif-containing protein 47 (TRIM47) and similar proteins; TRIM47, also known as gene overexpressed in astrocytoma protein (GOA) or RING finger protein 100 (RNF100), 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, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. It plays an important role in the process of dedifferentiation that is associated with astrocytoma tumorigenesis. This subfamily also includes RING finger protein 135 (RNF135). RNF135, also known as RIG-I E3 ubiquitin ligase (REUL) or Riplet, is a widely expressed E3 ubiquitin-protein ligase that consists of an N-terminal C3HC4-type RING-HC finger and C-terminal B30.2/SPRY and PRY motifs, but lacks the B-box and coiled-coil domains that are also typically present in TRIM proteins. RNF135 serves as a specific retinoic acid-inducible gene-I (RIG-I)-interacting protein that ubiquitinates RIG-I and specifically stimulates RIG-I-mediated innate antiviral activity to produce antiviral type-I interferon (IFN) during the early phase of viral infection. It also has been identified as a bio-marker and therapy target of glioblastoma. It associates with the ERK signal transduction pathway and plays a role in glioblastoma cell proliferation, migration and cell cycle.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1264232225 278 CVVCLSDLRDTLILPCRHlCLCTSCA----DTLRYQANNCPICRLPFR 321
Cdd:cd16604     3 CPICLDLLKDPVTLPCGH-SFCMGCLgalwGAGRGGRASCPLCRQTFP 49

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.

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                  ....*....|....*....|....*....|....*....|....*....
gi 1264232225 277 ECVVCLSDLRDTLILP----CRHLcLCTSCADT-LRYQANNCPICRLPF 320
Cdd:cd23121     3 CCAICLSDFNSDEKLRqlpkCGHI-FHHHCLDRwIRYNKITCPLCRADL 50

Uncharacterized conserved protein, contains RING Zn-finger [General function prediction only];

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1264232225 259 KNNQETKP-----SDDENSDNSSECVVCLSDLRDTLILPCRHLcLCTSCADTLR--YQANNCPICR 317
Cdd:COG5236    40 KNNLSAEPnlttsSADDTDEENMNCQICAGSTTYSARYPCGHQ-ICHACAVRLRalYMQKGCPLCR 104

second RING finger, HC subclass, found in mind bomb 1 (MIB1) and similar proteins; MIB1, also known as DAPK-interacting protein 1 (DIP-1) or zinc finger ZZ type with ankyrin repeat domain protein 2, is a large, multi-domain E3 ubiquitin-protein ligase that promotes ubiquitination of the cytoplasmic tails of Notch ligands, and thus plays an essential role in controlling metazoan development by Notch signaling. It is also involved in Wnt/beta-catenin signaling and nuclear factor (NF)-kappaB signaling, and has been implicated in innate immunity, neuronal function, genomic stability, and cell death. MIB1 contains an MZM region with two Mib-Herc2 domains flanking a ZZ zinc finger, a REP region including two tandem Mib repeats, an ANK region that spans ankyrin repeats, and a RNG region consisting of three C3HC4-type RING-HC fingers. This model corresponds to the second RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCADTLRyqanNCPICR 317
Cdd:cd16725     2 ECVVCSDKKASVLFKPCGHMCACEGCAALMK----KCVQCR 38

RING finger, HC subclass, found in RNA-binding protein MEX3C; MEX3C, also known as RING finger and KH domain-containing protein 2 (RKHD2), or RING finger protein 194 (RNF194), is an RNA-binding phosphoprotein that acts as a suppressor of chromosomal instability. It functions as an ubiquitin E3 ligase responsible for the post-transcriptional, HLA-A allotype-specific regulation of MHC class I molecules (MHC-I). It also modifies retinoic acid inducible gene-1 (RIG-I) in stress granules and plays a critical role in eliciting antiviral immune responses. Moreover, MEX3C plays an essential role in normal postnatal growth via enhancing the local expression of insulin-like growth factor 1 (IGF1) in bone. It may also be involved in metabolic regulation of energy balance. MEX3C contains two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. Like other MEX-3 family proteins, MEX3C shuttles between the nucleus and the cytoplasm via the CRM1-dependent export pathway.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1264232225 277 ECVVCLSDLRDTLILPCRHLCLCTSCADTL-RYQANNCPICRLPFRALLQI 326
Cdd:cd16722     3 DCVICFENEVIAALVPCGHNLFCMECANKIcEKETPSCPVCQTAVTQAIQI 53

RING finger, H2 subclass, found in RING finger proteins RNF111, RNF165, and similar proteins; The family includes RING finger proteins RNF111, RNF165, 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 also 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. The N-terminal half of RNF111 harbors three SUMO-interacting motifs (SIMs). 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). 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. Both RNF165 and RNF111 contain a C-terminal C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1264232225 278 CVVCLSDLRDTLI---LPCRHLcLCTSCADTLRYQANNCPICRL 318
Cdd:cd16474     3 CTICLSDFEEGEDvrrLPCMHL-FHQECVDQWLSTNKRCPICRV 45

RING finger, HC subclass, found in BRCA1-associated RING domain protein 1 (BARD-1) and similar proteins; BARD-1 is a critical factor in BRCA1-mediated tumor suppression and may also serve as a target for tumorigenic lesions in some human cancers. It associates with BRCA1 (breast cancer-1) to form a heterodimeric BRCA1/BARD1 complex that is responsible for maintaining genomic stability through nuclear functions involving DNA damage signaling and repair, transcriptional regulation, and cell cycle control. The BRCA1/BARD1 complex catalyzes autoubiquitination of BRCA1 and trans ubiquitination of other protein substrates. Its E3 ligase activity is dramatically reduced in the presence of UBX domain protein 1 (UBXN1). BARD-1 contains an C3HC4-type RING-HC finger that binds BRCA1 at its N-terminus and three tandem ankyrin repeats and tandem BRCT repeat domains at its C-terminus. The BRCT repeats bind CstF-50 (cleavage stimulation factor) to modulate mRNA processing and RNAP II stability in response to DNA damage.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1264232225 274 NSSECVVCLSDLRDTLIL-PCRHlCLCTSCADTlrYQANNCPICRLPFRA-LLQI 326
Cdd:cd16496    14 NLLRCSRCASILKEPVTLgGCEH-VFCRSCVGD--RLGNGCPVCDTPAWArDLQI 65

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1264232225 278 CVVCLSDLRDTL-ILPCRHLcLCTSCADT-LRYQANNCPICRLPfraLLQIRAVRKKP 333
Cdd:cd16531     4 CPICLGIIKNTMtVKECLHR-FCAECIEKaLRLGNKECPTCRKH---LPSRRSLRPDP 57

RING finger, HC subclass, found in RING finger protein 168 (RNF168) and similar proteins; RNF168 is an E3 ubiquitin-protein ligase that promotes noncanonical K27 ubiquitination to signal DNA damage. It, together with RNF8, functions as a DNA damage response (DDR) factor that promotes a series of ubiquitylation events on substrates, such as H2A and H2AX with H2AK13/15 ubiquitylation, facilitates recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of double-strand breaks (DSBs), and inhibits homologous recombination (HR) in cells deficient in the tumor suppressor BRCA1. RNF168 also promotes H2A neddylation, which antagonizes ubiquitylation of H2A and regulates DNA damage repair. Moreover, RNF168 forms a functional complex with RAD6A or RAD6B during the DNA damage response. RNF168 contains an N-terminal C3HC4-type RING-HC finger that catalyzes H2A-K15ub and interacts with H2A, and two MIU (motif interacting with ubiquitin) domains responsible for the interaction with K63 linked poly-ubiquitin.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1264232225 278 CVVCLSDLRDTLILPCRHlCLCTSCADTLRYQAN-NCPICRL 318
Cdd:cd16550     3 CPICLEILVEPVTLPCNH-TLCMPCFQSTVEKASlCCPLCRL 43

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 1264232225 277 ECVVCLSDLRDT---LILPCRHlCLCTSCADTLRYQANNCPICR 317
Cdd:cd16467     1 ECTICLGEYETGeklRRLPCSH-EFHSECVDRWLKENSSCPICR 43

RING finger, HC subclass, found in midline-1 (MID1) and similar proteins; MID1, also known as midin, midline 1 RING finger protein, putative transcription factor XPRF, RING finger protein 59 (RNF59), or tripartite motif-containing protein 18 (TRIM18), is a microtubule-associated E3 ubiquitin-protein ligase implicated in epithelial-mesenchymal differentiation, cell migration and adhesion, and programmed cell death along specific regions of the ventral midline during embryogenesis. It monoubiquinates the alpha4 subunit of protein phosphatase 2A (PP2A), promoting proteosomal degradation of the catalytic subunit of PP2A (PP2Ac) and preventing the A and B subunits from forming an active complex. It promotes allergen and rhinovirus-induced asthma through the inhibition of PP2A activity. It is strongly upregulated in cytotoxic lymphocytes (CTLs) and directs lytic granule exocytosis and cytotoxicity of killer T cells. Loss-of-function mutations in MID1 lead to the human X-linked Opitz G/BBB (XLOS) syndrome characterized by defective midline development during embryogenesis. MID1 belongs to the C-I 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 COS (carboxyl-terminal subgroup one signature) box, a fibronectin type III (FN3) domain, and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. MID1 hetero-dimerizes in vitro with its paralog MID2.

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gi 1264232225 278 CVVCLSDLRDTLILPCRHlCLCTSCADTL--RYQANN----------CPICR 317
Cdd:cd16753     8 CPICLELFEDPLLLPCAH-SLCFNCAHRIlvSHCASNesvesitafqCPTCR 58