RING finger, HC subclass, found in RING finger protein 10 (RNF10) and similar proteins; RNF10 is an E3 ubiquitin-protein ligase that interacts with mesenchyme Homeobox 2 (MEOX2) transcription factor, a regulator of the proliferation, differentiation and migration of vascular smooth muscle cells and cardiomyocytes; it enhances Meox2 activation of the p21 promoter. It also regulates the expression of myelin-associated glycoprotein (MAG) genes and is required for myelin production in Schwann cells of the peripheral nervous system. Moreover, RNF10 regulates retinoic acid-induced neuronal differentiation and the cell cycle exit of P19 embryonic carcinoma cells. RNF10 contains a C3HC4-type RING-HC finger and three putative nuclear localization signals.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTWRKCPICYDAIHAGDLK 263
Cdd:cd16536   2 QCPICLEPPVAPRITRCGHIFCWPCILRYLSLSEKKWRKCPICFESIHKKDLR 54

RING finger, HC subclass, found in RING finger protein 10 (RNF10) and similar proteins; RNF10 is an E3 ubiquitin-protein ligase that interacts with mesenchyme Homeobox 2 (MEOX2) transcription factor, a regulator of the proliferation, differentiation and migration of vascular smooth muscle cells and cardiomyocytes; it enhances Meox2 activation of the p21 promoter. It also regulates the expression of myelin-associated glycoprotein (MAG) genes and is required for myelin production in Schwann cells of the peripheral nervous system. Moreover, RNF10 regulates retinoic acid-induced neuronal differentiation and the cell cycle exit of P19 embryonic carcinoma cells. RNF10 contains a C3HC4-type RING-HC finger and three putative nuclear localization signals.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTWRKCPICYDAIHAGDLK 263
Cdd:cd16536   2 QCPICLEPPVAPRITRCGHIFCWPCILRYLSLSEKKWRKCPICFESIHKKDLR 54

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 21357563   212 CPICL-YPPVAAKLTRCGHAYCWPCLLHYLSlsdKTWRKCPIC 253
Cdd:pfam00097   1 CPICLeEPKDPVTLLPCGHLFCSKCIRSWLE---SGNVTCPLC 40

E3 ubiquitin-protein ligase RMA2; Provisional

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 21357563  209 ELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTWR------------KCPIC 253
Cdd:PLN03208  18 DFDCNICLDQVRDPVVTLCGHLFCWPCIHKWTYASNNSRQrvdqydhkreppKCPVC 74

RING finger, HC subclass, found in RING finger protein 10 (RNF10) and similar proteins; RNF10 is an E3 ubiquitin-protein ligase that interacts with mesenchyme Homeobox 2 (MEOX2) transcription factor, a regulator of the proliferation, differentiation and migration of vascular smooth muscle cells and cardiomyocytes; it enhances Meox2 activation of the p21 promoter. It also regulates the expression of myelin-associated glycoprotein (MAG) genes and is required for myelin production in Schwann cells of the peripheral nervous system. Moreover, RNF10 regulates retinoic acid-induced neuronal differentiation and the cell cycle exit of P19 embryonic carcinoma cells. RNF10 contains a C3HC4-type RING-HC finger and three putative nuclear localization signals.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTWRKCPICYDAIHAGDLK 263
Cdd:cd16536   2 QCPICLEPPVAPRITRCGHIFCWPCILRYLSLSEKKWRKCPICFESIHKKDLR 54

RING finger, HC subclass, found in helicase-like transcription factor (HLTF) and similar proteins; HLTF, also known as DNA-binding protein/plasminogen activator inhibitor 1 regulator, HIP116, RING finger protein 80, SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A member 3, or sucrose nonfermenting protein 2-like 3, is a yeast RAD5 homolog found in mammals. It has both E3 ubiquitin ligase and DNA helicase activities, and plays a pivotal role in the template-switching pathway of DNA damage tolerance. It is involved in Lys-63-linked poly-ubiquitination of proliferating cell nuclear antigen (PCNA) at Lys-164 and in the regulation of DNA damage tolerance. It shows double-stranded DNA translocase activity with 3'-5' polarity, thereby facilitating regression of the replication fork. HLTF contains an N-terminal HIRAN (HIP116 and RAD5 N-terminal) domain, a SWI/SNF helicase domain that is divided into N- and C-terminal parts by an insertion of a C3HC4-type RING-HC finger involved in the poly-ubiquitination of PCNA.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21357563 212 CPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDktwRKCPICYDAIHAGDL 262
Cdd:cd16509   6 CAICLDSLTNPVITPCAHVFCRRCICEVIQREK---AKCPMCRAPLSASDL 53

RING finger, HC subclass, found in breast cancer type 1 susceptibility protein (BRCA1) and similar proteins; BRCA1, also known as RING finger protein 53 (RNF53), is a RING finger protein encoded by the tumor suppressor gene BRCA1 that regulates all DNA double-strand break (DSB) repair pathways. BRCA1 is frequently mutated in patients with hereditary breast and ovarian cancer (HBOC). Its mutation is also associated with an increased risk of pancreatic, stomach, laryngeal, fallopian tube, and prostate cancer. It plays an important role in the DNA damage response signaling and has been implicated in various cellular processes such as cell cycle regulation, transcriptional regulation, chromatin remodeling, DNA DSBs, and apoptosis. BRCA1 contains an N-terminal C3HC4-type RING-HC finger, and two BRCT (BRCA1 C-terminus domain) repeats at the C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 21357563 210 LQCPICL---YPPVAaklTRCGHAYCWPCLLHYLSLSDKTWRkCPIC 253
Cdd:cd16498  17 LECPICLellKEPVS---TKCDHQFCRFCILKLLQKKKKPAP-CPLC 59

RING finger, HC subclass, found in RING finger protein 170 (RNF170) and similar proteins; RNF170, also known as putative LAG1-interacting protein, is an endoplasmic reticulum (ER) membrane-bound E3 ubiquitin-protein ligase that mediates ubiquitination-dependent degradation of type-I inositol 1,4,5-trisphosphate (IP3) receptors (ITPR1) via the endoplasmic-reticulum-associated protein degradation (ERAD) pathway. A point mutation (arginine to cysteine at position 199) in the RNF170 gene is linked with autosomal-dominant sensory ataxia (ADSA), a disease characterized by neurodegeneration in the posterior columns of the spinal cord. RNF170 contains a C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLHYlslsdktWR--------KCPIC 253
Cdd:cd16553   3 ECPICLQDARFPVETNCGHLFCGPCIITY-------WRhgswlgavSCPVC 46

RING finger, HC subclass, found in radiation sensitivity protein 5 (RAD5) and similar proteins; RAD5, also known as revertibility protein 2 (REV2), or DNA repair protein RAD5, is a probable helicase, and a member of the UBC2/RAD6 epistasis group. It functions with the DNA repair protein RAD18 in error-free postreplication DNA repair. It is involved in the maintenance of wild-type rates of instability of simple repetitive sequences such as poly(GT) repeats. It may also be involved in maintaining a balance which acts in favor of error-prone non-homologous joining during DNA double-strand breaks repairs. It recruits the UBC13-MMS2 dimer to chromatin for DNA repair. RAD5 contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 21357563 209 ELQCPICLYPPV---AAKLTRCGHAYCWPCLLHYLSL--SDKTWRKCPICYDAI 257
Cdd:cd23131   3 EVECSICTQEPIevgEVVFTECGHSFCEDCLLEYIEFqnKKKLDLKCPNCREPI 56

RING finger, HC subclass, found in RING finger protein 5 (RNF5) and similar proteins; RNF5, also known as protein G16 or Ram1, is an E3 ubiquitin-protein ligase anchored to the outer membrane of the endoplasmic reticulum (ER). It acts at early stages of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) biosynthesis and functions as a target for therapeutic modalities to antagonize mutant CFTR proteins in CF patients carrying the F508del allele. It also regulates the turnover of specific G protein-coupled receptors by ubiquitinating JNK-associated membrane protein (JAMP) and preventing proteasome recruitment. RNF5 limits basal levels of autophagy and influences susceptibility to bacterial infection through the regulation of ATG4B stability. It is also involved in the degradation of Pendrin, a transmembrane chloride/anion exchanger highly expressed in thyroid, kidney, and inner ear. RNF5 plays an important role in cell adhesion and migration. It can modulate cell migration by ubiquitinating paxillin. Furthermore, RNF5 interacts with virus-induced signaling adaptor (VISA) at mitochondria in a viral infection-dependent manner, and further targets VISA at K362 and K461 for K48-linked ubiquitination and degradation after viral infection. It also negatively regulates virus-triggered signaling by targeting MITA, also known as STING, for ubiquitination and degradation at the mitochondria. In addition, RNF5 determines breast cancer response to ER stress-inducing chemotherapies through the regulation of the L-glutamine carrier proteins SLC1A5 and SLC38A2 (SLC1A5/38A2). It also has been implicated in muscle organization and in recognition and processing of misfolded proteins. RNF5 contains a C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTwRKCPICYDAI 257
Cdd:cd16743   2 ECNICLETARDAVVSLCGHLFCWPCLHQWLETRPER-QECPVCKAGI 47

RING finger, HC subclass, found in RING finger protein 185 (RNF185) and similar proteins; RNF185 is an E3 ubiquitin-protein ligase of endoplasmic reticulum-associated degradation (ERAD) that targets cystic fibrosis transmembrane conductance regulator (CFTR). It controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical ERAD model substrates. It also negatively regulates osteogenic differentiation by targeting dishevelled2 (Dvl2), a key mediator of the Wnt signaling pathway, for degradation. Moreover, RNF185 regulates selective mitochondrial autophagy through interaction with the Bcl-2 family protein BNIP1. It also plays an important role in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. RNF185 contains a C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLHYLsLSDKTWRKCPICYDAI 257
Cdd:cd16744   2 ECNICLDTAKDAVVSLCGHLFCWPCLHQWL-ETRPNRQVCPVCKAGI 47

RING finger, HC subclass, found in Saccharomyces cerevisiae POB3/SPT16 histone-associated protein 1 (ScPSH1) and similar proteins; ScPSH1 is a Cse4-specific E3 ubiquitin ligase that interacts with the kinetochore protein Pat1 and targets the degradation of budding yeast centromeric histone H3 variant, CENP-ACse4, which is essential for faithful chromosome segregation. ScPSH1 contains a C3HC4-type RING-HC finger and a DNA directed RNA polymerase domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21357563 206 TTEELQCPIC---LYPPVaakLTRCGHAYCWPCLLHYLSLSDKtwRKCPIC 253
Cdd:cd16568   1 ILETQECIICheyLYEPM---VTTCGHTYCYTCLNTWFKSNRS--LSCPDC 46

RING finger, HC subclass, found in Arabidopsis thaliana protein CHROMATIN REMODELING 27 (CHR27) and similar proteins; CHR27, also called protein SNF2-RING-HELICASE-LIKE 1, is a probable helicase-like transcription factor involved in transcriptional gene silencing. It associates with SUVR2 and contributes to transcriptional gene silencing at RNA-directed DNA methylation (RdDM) target loci but also at RdDM-independent target loci. It may be involved in nucleosome positioning to form ordered nucleosome arrays on chromatin. It associates with SUVR2 and functions redundantly with FRG2. It is required for the efficient methylation of a broad range of RdDM target loci. CHR27 contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21357563 212 CPICLYPPVAAKLTRCGHAYCWPCLLHYLSlSDKTWR---KCPIC 253
Cdd:cd23142   3 CPICNDPPEDAVVTLCGHVFCCECVFQYLS-SDRTCRqfnHCPLC 46

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21357563 211 QCPICLYPPVAAK-LTRCGHAYCWPCLLHylSLSDKTwrKCPIC 253
Cdd:cd16506   2 TCPICLDEIQNKKtLEKCKHSFCEDCIDR--ALQVKP--VCPVC 41

RING finger, HC subclass, found in Arabidopsis thaliana proteolysis 1 protein (PRT1) and similar proteins; PRT1, also called RING-type E3 ubiquitin transferase PRT1, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of target proteins. It functions in the N-end rule pathway of protein degradation, where it specifically recognizes and ubiquitinates proteins with an N-terminal bulky aromatic amino acid (Phe). It does not act on aliphatic hydrophobic and basic N-terminal residues (Arg or Leu) containing proteins. PRT1 contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 21357563 208 EELQCPIC---LYPPVaakLTRCGHAYCWPCLLHYLSLSDKTwrKCPICYDA 256
Cdd:cd23132   1 EEFLCCICldlLYKPV---VLECGHVFCFWCVHRCMNGYDES--HCPLCRRP 47

second RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the second RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 21357563 209 ELQCPIC---LYPPVAaklTRCGHAYCWPCLLHYLSLSDktwrKCPIC 253
Cdd:cd16514   1 DLECSLClrlLYEPVT---TPCGHTFCRACLERCLDHSP----KCPLC 41

Modified RING finger, HC subclass (C3HC3D-type), found in ligand of Numb protein LNX1, LNX2, and similar proteins; The ligand of Numb protein X (LNX) family, also known as PDZ and RING (PDZRN) family, includes LNX1-5, which can interact with Numb, a key regulator of neurogenesis and neuronal differentiation. LNX5 (also known as PDZK4 or PDZRN4L) shows high sequence homology to LNX3 and LNX4, but it lacks the RING domain. LNX1-4 proteins function as E3 ubiquitin ligases and have a unique domain architecture consisting of an N-terminal RING-HC finger for E3 ubiquitin ligase activity and either two or four PDZ domains necessary for substrate-binding. LNX1/LNX2-like proteins contain a modified C3HC3D-type RING-HC finger and four PDZ domains. This model corresponds to the RING finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21357563 209 ELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLslsdKTWRKCPI 252
Cdd:cd16637   1 DLTCHICLQPLVEPLDTPCGHTFCYKCLTNYL----KIQQCCPL 40

RING-finger-containing E3 ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21357563 211 QCPICLYPPVAAKLTRCGHAYCWPCLLhyLSLSDKTWRKCPIC 253
Cdd:COG5574 217 KCFLCLEEPEVPSCTPCGHLFCLSCLL--ISWTKKKYEFCPLC 257

Modified RING finger found in peroxin-12 (PEX12) and similar proteins; PEX12, also known as peroxisome assembly protein 12 or peroxisome assembly factor 3 (PAF-3), is a RING finger domain-containing integral membrane peroxin required for protein import into peroxisomes. Mutations in human PEX12 result in the peroxisome deficiency Zellweger syndrome of complementation group III (CG-III), a lethal neurological disorder. PEX12 also functions as an E3-ubiquitin ligase that facilitates the PEX4-dependent monoubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation. PEX12 contains a modified RING finger that lacks the third, fourth, and eighth zinc-binding residues of the consensus RING finger motif, suggesting PEX12 may only bind one zinc ion.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 21357563 212 CPICLYPPV-AAKLTRCGHAYCWPCLLHYLslsdKTWRKCPI 252
Cdd:cd16451   3 CPLCRKKRTnPTALATSGYVFCYPCIYRYV----KEHGRCPV 40

RING finger, HC subclass, found in RING finger protein 138 (RNF138) and similar proteins; RNF138, also known as Nemo-like kinase-associated RING finger protein (NARF) or NLK-associated RING finger protein, is an E3 ubiquitin-protein ligase that plays an important role in glioma cell proliferation, apoptosis, and cell cycle. It specifically cooperates with the E2 conjugating enzyme E2-25K (Hip-2/UbcH1), regulates the ubiquitylation and degradation of T cell factor/lymphoid enhancer factor (TCF/LEF), and further suppresses Wnt-beta-catenin signaling. RNF138, together with three closely related proteins: RNF114, RNF125 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).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 21357563 208 EELQCPICLYP---PVaaKLTRCGHAYCWPCLLHYLslsDKTWRKCPIC 253
Cdd:cd16544   1 AELTCPVCQEVlkdPV--ELPPCRHIFCKACILLAL---RSSGARCPLC 44

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        40
                ....*....|....*....|....*....|....*....|....*
gi 21357563 211 QCPICLYPPVAAK--LTRCGHAYCWPCLLHYLSLSDKTWRKCPIC 253
Cdd:cd16471   1 ECPICLCAFKGRKctLLSCSHVFHEACLSAFEKFIESKNQKCPLC 45

RING finger, HC subclass, found in Saccharomyces cerevisiae DNA repair protein RAD16, Schizosaccharomyces pombe rhp16, and similar proteins; Budding yeast RAD16, also known as ATP-dependent helicase RAD16, is encoded by a yeast excision repair gene homologous to the recombinational repair gene RAD54 and to the SNF2 gene involved in transcriptional activation. It is a component of the global genome repair (GGR) complex that promotes global genome nucleotide excision repair (GG-NER) by removing DNA damage from non-transcribing DNA. RAD16 is involved in differential repair of DNA after UV damage, and repairs preferentially the MAT-alpha locus compared with the HML-alpha locus. Fission yeast rhp16, also known as ATP-dependent helicase rhp16, is a RAD16 homolog. It is involved in GGR via nucleotide excision repair (NER), in conjunction with rhp7, after UV irradiation. Both RAD16 and rhp16 contain a C3HC4-type RING-HC finger, as well as a DEAD-like helicase domain and a helicase superfamily C-terminal domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21357563 210 LQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTWRKCPICY 254
Cdd:cd16567   1 LVCGICHEEAEDPVVARCHHVFCRACVKEYIESAPGGKVTCPTCH 45

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 21357563 208 EELQCPICL---YPPvaAKLTRCGHAYCWPClLHYLSLSDKTWRKCPIC 253
Cdd:cd16554   1 ESLTCPVCLdlyYDP--YMCYPCGHIFCEPC-LRQLAKSSPKNTPCPLC 46

RING finger, HC subclass, found in protein Deltex-3-like (DTX3L) and similar proteins; DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), is a RING-domain E3 ubiquitin-protein ligase that regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. DTX3L has a unique N-terminus, but lacks the highly basic N-terminal motif and the central proline-rich motif present in other Deltex (DTX) family members, such as DTX1, DTX2, and DTX4. Moreover, its C-terminal region is highly homologous to DTX3. It includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N-terminus and further enhance self-ubiquitination.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 21357563 207 TEELQCPICLYPPVAAK-LTRCGHAYCWPCLLHylSLSDKTwrKCPIC 253
Cdd:cd16712   1 QEEDECPICMDRISNKKvLPKCKHVFCAACIDK--AMKYKP--VCPVC 44

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21357563 212 CPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDktwrKCPICY 254
Cdd:cd16476   3 CAICYQEMKEARITPCNHFFHGLCLRKWLYVQD----TCPLCH 41

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

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 21357563 207 TEELQCPICLYP---PVAaklTRCGHAYCWPCLlhylslsDKTWRK-------CPIC 253
Cdd:cd16597   3 EEELTCSICLELfkdPVT---LPCGHNFCGVCI-------EKTWDSqhgseysCPQC 49

Modified RING finger, HC subclass (C3HC3D-type), found in ligand of numb protein X 2 (LNX2); LNX2, also known as numb-binding protein 2, or PDZ domain-containing RING finger protein 1 (PDZRN1), is a PDZ domain-containing RING-type E3 ubiquitin ligase responsible for the ubiquitination and degradation of Numb, a component of the Notch signaling pathway that functions in the specification of cell fates during development and is known to control cell numbers during neurogenesis in vertebrates. It interacts with contactin-associated protein 4 (Caspr4, also known as CNTNAP4) in a PDZ domain-dependent manner, which modulates the proliferation and neuronal differentiation of neural progenitor cells (NPCs). LNX2 contains an N-terminal modified C3HC3D-type RING-HC finger, a NPAF motif for Numb/ Numblike-LNX interaction, and four PDZ domains necessary for the binding of substrates, including ErbB2, RhoC, the presynaptic protein CAST, the melanoma/cancer-testis antigen MAGEB18 and several proteins associated with cell junctions, such as JAM4 and the Coxsackievirus and adenovirus receptor (CAR).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21357563 208 EELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDktwrKCPI 252
Cdd:cd16780   2 DDLVCHICLQPLLQPLDTPCGHTFCFKCLRNFLQEKD----FCPL 42

first RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the first RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 21357563 208 EELQCPIC---LYPPVAaklTRCGHAYCWPCLLHYLSlsdktwRKCPICYDAIHAG 260
Cdd:cd16513   1 DLLSCPLCrglLFEPVT---LPCGHTFCKRCLERDPS------SRCRLCRLKLSPG 47

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3) and similar proteins; DTX3, also known as RING finger protein 154 (RNF154), is an E3 ubiquitin-protein ligase that belongs to the Deltex (DTX) family. In contrast to other DTXs, DTX3 does not contain two N-terminal Notch-binding WWE domains, but a short unique N-terminal domain, suggesting it does not interact with the intracellular domain of Notch. Its C-terminal region includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 21357563 209 ELQCPICLYPPVAAK-LTRCGHAYCWPCLLHYLSLSdktwRKCPIC 253
Cdd:cd16711   1 EETCPICLGEIQNKKtLDKCKHSFCEDCITRALQVK----KACPMC 42

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM13, TRIM59 and similar proteins; TRIM13 and TRIM59, two closely related tripartite motif-containing proteins, belong to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, followed by a C-terminal transmembrane domain. TRIM13, also known as B-cell chronic lymphocytic leukemia tumor suppressor Leu5, leukemia-associated protein 5, putative tumor suppressor RFP2, RING finger protein 77 (RNF77), or Ret finger protein 2, is an endoplasmic reticulum (ER) membrane anchored E3 ubiquitin-protein ligase that interacts with proteins localized to the ER, including valosin-containing protein (VCP), a protein indispensable for ER-associated degradation (ERAD). TRIM59, also known as RING finger protein 104 (RNF104) or tumor suppressor TSBF-1, is a putative E3 ubiquitin-protein ligase that functions as a novel multiple cancer biomarker for immunohistochemical detection of early tumorigenesis.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 21357563 208 EELQCPIC---LYPPvaaKLTRCGHAYCWPCLLHYLSLSDKT---WRKCPIC 253
Cdd:cd16581   1 EELTCSICyniFDDP---KILPCSHTFCKNCLEKLLAASGYYllaSLKCPTC 49

RING finger, HC subclass, found in tripartite motif-containing protein TRIM50, TRIM73, TRIM74 and similar proteins; TRIM50 is a stomach-specific E3 ubiquitin-protein ligase, encoded by the Williams-Beuren syndrome (WBS) TRIM50 gene, which regulates vesicular trafficking for acid secretion in gastric parietal cells. It colocalizes, interacts with, and increases the level of p62/SQSTM1, a multifunctional adaptor protein implicated in various cellular processes including the autophagy clearance of polyubiquitinated protein aggregates. It also promotes the formation and clearance of aggresome-associated polyubiquitinated proteins through the interaction with histone deacetylase 6 (HDAC6), a tubulin specific deacetylase that regulates microtubule-dependent aggresome formation. TRIM50 can be acetylated by PCAF and p300. TRIM50 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. This subfamily also includes two paralogs of TRIM50, tripartite motif-containing protein 73 (TRIM73), also known as tripartite motif-containing protein 50B (TRIM50B), and tripartite motif-containing protein 74 (TRIM74), also known as tripartite motif-containing protein 50C (TRIM50C), both of which are WBS-related genes encoding proteins that may also act as E3 ligases. In contrast with TRIM50, TRIM73 and TRIM74 belong to the C-V subclass of TRIM family of proteins that are defined by N-terminal RBCC domains only.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21357563 210 LQCPICLYPPVAAKLTRCGHAYCWPClLHYLSLSDKTWRKCPIC 253
Cdd:cd16605   1 LLCPICLEVFKEPLMLQCGHSYCKSC-LVSLSGELDGQLLCPVC 43

RING finger, HC subclass, found in RING finger protein RNF20, RNF40, and similar proteins; RNF20, also known as BRE1A, and RNF40, also known as BRE1B, are E3 ubiquitin-protein ligases that work together to form a heterodimeric 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. RNF20 regulates the cell cycle and differentiation of neural precursor cells (NPCs) and links histone H2B ubiquitylation with inflammation and inflammation-associated cancer. RNF40, also known as 95 kDa retinoblastoma-associated protein (RBP95), was identified as a novel leucine zipper retinoblastoma protein (pRb)-associated protein that may function as a regulation factor in RNA polymerase II-mediated transcription and/or transcriptional processing. All subfamily members contain a C3HC4-type RING-HC finger at its C-terminus.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 21357563 200 EQINIQTTEeLQCPICLYPPVAAKLTRCGHAYCWPCLLhylSLSDKTWRKCPICYDAIHAGD 261
Cdd:cd16704   2 EEIKEYKAR-LTCPCCNTRKKDAVLTKCFHVFCFECLK---TRYETRQRKCPKCNAAFGAND 59

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) and similar proteins; TRAF6, also known as interleukin-1 signal transducer or RING finger protein 85 (RNF85), is a cytoplasmic adapter protein that mediates signals induced by the tumor necrosis factor receptor (TNFR) superfamily and Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) family. It functions as a mediator involved in the activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways, as well as in IL-1R-mediated activation of NF-kappaB. TRAF6 is also an oncogene that plays a vital role in K-RAS-mediated oncogenesis. TRAF6 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21357563 210 LQCPICLYPPVAAKLTRCGHAYCWPCLLHylSLSDkTWRKCPI 252
Cdd:cd16643   2 YECPICLMALREPVQTPCGHRFCKACILK--SIRE-AGHKCPV 41

RING finger, HC subclass, found in tripartite motif-containing protein TRIM21 and similar proteins; TRIM21, also known as 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A, Ro(SS-A), RING finger protein 81 (RNF81), or Sjoegren syndrome type A antigen (SS-A), is a ubiquitously expressed E3 ubiquitin-protein ligase and a high affinity antibody receptor uniquely expressed in the cytosol of mammalian cells. As a cytosolic Fc receptor, TRIM21 binds the Fc of virus-associated antibodies and targets the complex in the cytosol for proteasomal degradation in a process known as antibody-dependent intracellular neutralization (ADIN), and provides an intracellular immune response to protect host defense against pathogen infection. It shows remarkably broad isotype specificity as it does not only bind IgG, but also IgM and IgA. Moreover, TRIM21 promotes the cytosolic DNA sensor cGAS and the cytosolic RNA sensor RIG-I sensing of viral genomes during infection by antibody-opsonized virus. It stimulates inflammatory signaling and activates innate transcription factors, such as nuclear factor-kappaB (NF-kappaB). TRIM21 also plays an essential role in p62-regulated redox homeostasis, suggesting it may be a viable target for treating pathological conditions resulting from oxidative damage. Furthermore, TRIM21 may have implications for various autoimmune diseases associated with uncontrolled antiviral signaling through the regulation of Nmi-IFI35 complex-mediated inhibition of innate antiviral response. TRIM21 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 21357563 208 EELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTwrkCPIC 253
Cdd:cd16596   8 EEVTCPICLDPFVEPVSIECGHSFCQECISQVGKGGGSV---CPVC 50

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 21357563 208 EELQCPICLYPPVAAK---LTRCGHAYCWPCLLHYLSLSDktwrKCPIC 253
Cdd:cd23116   1 DEDVCPTCLEGYTEENpklLTKCGHHFHLACIYEWMERSE----RCPVC 45

RING finger, H2 subclass, found in Saccharomyces cerevisiae alcohol-sensitive RING finger protein 1 (ASR1) and similar proteins; ASR1 is required for tolerance to alcohol. It signals alcohol stress to the nucleus. ASR1 contains a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21357563 211 QCPICL--YPPVAAKLTRCGHAYCWPCLLHYLSLSDKtwRKCPIC 253
Cdd:cd23120   3 ECPICLeeMNSGTGYLADCGHEFHLTCIREWHNKSGN--LDCPIC 45

RING finger, HC subclass, found in tripartite motif-containing protein 77 (TRIM77) and similar proteins; TRIM77 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 two consecutive zinc-binding domains, a C3HC4-type RING-HC finger and Bbox2, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain.

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                ....*....|....*....|....*....|....*....|....*....|..
gi 21357563 207 TEELQCPIC---LYPPVAaklTRCGHAYCWPCLLHylsLSDKTW--RKCPIC 253
Cdd:cd16543   1 EDQLTCSICldlLKDPVT---IPCGHSFCMNCITL---LWDRKQgvPSCPQC 46

Modified RING finger, HC subclass (C3HC3D-type), found in ligand of numb protein X 1 (LNX1); LNX1, also known as numb-binding protein 1 or PDZ domain-containing RING finger protein 2, is a PDZ domain-containing RING-type E3 ubiquitin ligase responsible for the ubiquitination and degradation of Numb, a component of the Notch signaling pathway that functions in the specification of cell fates during development and is known to control cell numbers during neurogenesis in vertebrates. LNX1 contains an N-terminal modified C3HC3D-type RING-HC finger, a NPAY motif for Numb-LNX interaction, and four PDZ domains necessary for the binding of substrates, including CAR, ErbB2, SKIP, JAM4, CAST, c-Src, Claudins, RhoC, KCNA4, PAK6, PLEKHG5, PKC-alpha1, TYK2, PDZ-binding kinase (PBK), LNX2, and itself.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21357563 209 ELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDktwrKCPI 252
Cdd:cd16779   1 DLICHICLQALIQPLDTPCGHTYCTLCLTNFLVEKD----FCPM 40

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 21357563 210 LQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDktwRKCPICYDAIHAGDLKS 264
Cdd:cd16499   7 LKCSVCNDRFKDVIITKCGHVFCNECVQKRLETRQ---RKCPGCGKAFGANDVQR 58

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

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                ....*....|....*....|....*....|....*....|....*....
gi 21357563 209 ELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLslsdKTWRKCPICYDAI 257
Cdd:cd16535   1 ELQCSICSELFIEAVTLNCSHSFCSYCITEWM----KRKKECPICRKPI 45

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM5, TRIM6, TRIM22, TRIM34 and similar proteins; TRIM5, TRIM6, TRIM22, and TRIM34, four closely related tripartite motif-containing proteins, belong 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. TRIM5, also known as RING finger protein 88 (RNF88), is a capsid-specific restriction factor that prevents infection from non-host-adapted retroviruses in a species-specific manner by binding to and destabilizing the retroviral capsid lattice before reverse transcription is completed. Its retroviral restriction activity correlates with the ability to activate TAK1-dependent innate immune signaling. TRIM5 also acts as a pattern recognition receptor that activates innate immune signaling in response to the retroviral capsid lattice. Moreover, TRIM5 plays a role in regulating autophagy through activation of autophagy regulator BECN1 by causing its dissociation from its inhibitors BCL2 and TAB2. It also plays a role in autophagy by acting as a selective autophagy receptor which recognizes and targets HIV-1 capsid protein p24 for autophagic destruction. TRIM6, also known as RING finger protein 89 (RNF89), is an E3-ubiquitin ligase that cooperates with the E2-ubiquitin conjugase UbE2K to catalyze the synthesis of unanchored K48-linked polyubiquitin chains, and further stimulates the interferon-I kappa B kinase epsilon (IKKepsilon) kinase-mediated antiviral response. It also regulates the transcriptional activity of Myc during the maintenance of embryonic stem (ES) cell pluripotency, and may act as a novel regulator for Myc-mediated transcription in ES cells. TRIM22, also known as 50 kDa-stimulated trans-acting factor (Staf-50) or RING finger protein 94 (RNF94), is an E3 ubiquitin-protein ligase that plays an integral role in the host innate immune response to viruses. It has been shown to inhibit the replication of a number of viruses, including HIV-1, hepatitis B, and influenza A. TRIM22 acts as a suppressor of basal HIV-1 long terminal repeat (LTR)-driven transcription by preventing the transcription factor specificity protein 1 (Sp1) binding to the HIV-1 promoter. It also controls FoxO4 activity and cell survival by directing Toll-like receptor 3 (TLR3)-stimulated cells toward type I interferon (IFN) type I gene induction or apoptosis. Moreover, TRIM22 can activate the noncanonical nuclear factor-kappaB (NF-kappaB) pathway by activating I kappa B kinase alpha (IKKalpha). It also regulates nucleotide binding oligomerization domain containing 2 (NOD2)-dependent activation of interferon-beta signaling and nuclear factor-kappaB. TRIM34, also known as interferon-responsive finger protein 1 or RING finger protein 21 (RNF21), may function as antiviral protein that contribute to the defense against retroviral infections.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 21357563 202 INIQttEELQCPICLYPPVAAKLTRCGHAYCWPCLL--HYLSLSDKTWRKCPIC 253
Cdd:cd16591   1 VNIK--EEVTCPICLELLTEPLSLDCGHSFCQACITanHKESVNQEGESSCPVC 52

RING finger, HC subclass, found in RING finger protein 40 (RNF40); RNF40, also known as BRE1B or 95 kDa retinoblastoma-associated protein (RBP95), was identified as a novel leucine zipper retinoblastoma protein (pRb)-associated protein that may function as a regulation factor in RNA polymerase II-mediated transcription and/or transcriptional processing. RNF40 also functions as an E3 ubiquitin-protein ligase that forms a heterodimeric complex with BRE1B, also known as RNF40, to 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. It cooperates with SUPT16H to induce dynamic changes in chromatin structure during DSB repair. RNF40 contains a C3HC4-type RING-HC finger at the C-terminus.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 21357563 209 ELQCPICLYPPVAAKLTRCGHAYCWPCLlhyLSLSDKTWRKCPICYDAIHAGDL 262
Cdd:cd16815  23 RLTCPCCNTRKKDAVLTKCFHVFCFECV---KTRYESRQRKCPKCNAAFGAHDF 73

RING finger, HC subclass, found in tripartite motif-containing protein 13 (TRIM13) and similar proteins; TRIM13, also known as B-cell chronic lymphocytic leukemia tumor suppressor Leu5, leukemia-associated protein 5, putative tumor suppressor RFP2, RING finger protein 77 (RNF77), or Ret finger protein 2, is an endoplasmic reticulum (ER) membrane anchored E3 ubiquitin-protein ligase that interacts with proteins localized to the ER, including valosin-containing protein (VCP), a protein indispensable for ER-associated degradation (ERAD). It also targets the known ER proteolytic substrate CD3-delta, but not the N-end rule substrate Ub-R-YFP (yellow fluorescent protein) for degradation. Moreover, TRIM13 regulates ubiquitination and degradation of NEMO to suppress tumor necrosis factor (TNF) induced nuclear factor-kappaB (NF- kappa B) activation. It is also involved in NF-kappaB p65 activation and nuclear factor of activated T-cells (NFAT)-dependent activation of c-Rel upon T-cell receptor engagement. Furthermore, TRIM13 negatively regulates melanoma differentiation-associated gene 5 (MDA5)-mediated type I interferon production. It also regulates caspase-8 ubiquitination, translocation to autophagosomes, and activation during ER stress induced cell death. Meanwhile, TRIM13 enhances ionizing radiation-induced apoptosis by increasing p53 stability and decreasing AKT kinase activity through MDM2 and AKT degradation. TRIM13 belongs to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region. In addition, TRIM13 contains a C-terminal transmembrane domain.

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                ....*....|....*....|....*....|....*....|....*....|.
gi 21357563 208 EELQCPICLYPPVAAKLTRCGHAYCWPCLLHYLSLSDKT--WR---KCPIC 253
Cdd:cd16762   2 EDLTCPICCCLFDDPRVLPCSHNFCKKCLEGILEGNVRTmlWRppfKCPTC 52

RING finger found in polycomb group RING finger protein 2 (PCGF2) and similar proteins; PCGF2, also known as DNA-binding protein Mel-18, RING finger protein 110 (RNF110), or zinc finger protein 144 (ZNF144), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR). It serves as the core component of a canonical Polycomb repressive complex 1 (PRC1), which is composed of a chromodomain-containing protein (CBX2, CBX4, CBX6, CBX7 or CBX8) and a Polyhomeotic protein (PHC1, PHC2, or PHC3). Like other PCGF homologs, PCGF2 associates with ring finger protein 2 (RNF2) to form a RNF2-PCGF heterodimer, which is catalytically competent as an E3 ubiquitin transferase and is the scaffold for the assembly of additional components. Moreover, PCGF2 uniquely regulates PRC1 to specify mesoderm cell fate in embryonic stem cells. It is required for PRC1 stability and maintenance of gene repression in embryonic stem cells (ESCs) and essential for ESC differentiation into early cardiac-mesoderm precursors. PCGF2 also plays a significant role in the angiogenic function of endothelial cells (ECs) by regulating endothelial gene expression. Furthermore, PCGF2 is a SUMO-dependent regulator of hormone receptors. It facilitates the deSUMOylation process by inhibiting PCGF4/BMI1-mediated ubiquitin-proteasomal degradation of SUMO1/sentrin-specific protease 1 (SENP1). It is also a novel negative regulator of breast cancer stem cells (CSCs) that inhibits the stem cell population and in vitro and in vivo self-renewal through the inactivation of Wnt-mediated Notch signaling. PCGF2 contains a C3HC4-type RING-HC finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 21357563 204 IQTTE---ELQCPICL-YPPVAAKLTRCGHAYCWPCLLHYLslsdKTWRKCPICYDAIHAG 260
Cdd:cd16734   6 IKITElnpHLMCALCGgYFIDAATIVECLHSFCKTCIVRYL----ETNKYCPMCDVQVHKT 62

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.

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                ....*....|....*....|....*....|....*....|....*.
gi 21357563 212 CPICLYPPVAAKLTRCGHAYCwpCLLHYLSLSDKtwRKCPICYDAI 257
Cdd:cd16648   4 CVICLSNPRSCVFLECGHVCS--CIECYEALPSP--KKCPICRSFI 45

SP-RING finger found in the Siz/PIAS RING (SP-RING) family of SUMO E3 ligases; The SP-RING family includes PIAS (protein inhibitor of activated STAT) proteins, Zmiz proteins, and Siz proteins from plants and fungi. PIAS proteins modulate the activity of several transcription factors and act as E3 ubiquitin ligases in the sumoylation pathway. There are four members: PIAS1, PIAS2 (also known as PIASx), PIAS3, and PIAS4 (also known as PIASy). PIAS proteins were initially identified as inhibitors of activated STAT only, but are now known to interact with and modulate several other proteins, including androgen receptor (AR), tumor suppressor p53, and the transforming growth factor-beta (TGF-beta) signaling protein SMAD. They interact with STATs in a cytokine-dependent manner. PIAS proteins have SUMO E3-ligase activity and interaction of PIAS proteins with transcription factors often results in sumoylation of that protein. Zmiz1 (Zimp10) and its homolog Zmiz2 (Zimp7) were initially identified in humans as androgen receptor (AR) interacting proteins that function as transcriptional co-activators. They interact with BRG1, the catalytic subunit of the SWI-SNF remodeling complex. They also associate with other hormone nuclear receptors and transcription factors such as p53 and Smad3/Smad4, and regulate transcription of specific target genes by altering their chromatin structure. SIZ1 proteins from plants and fungi are also founding members of this family. SIZ1-mediated conjugation of SUMO1 and SUMO2 to other intracellular proteins is essential in Arabidopsis. Yeast SIZ proteins are SUMO E3 ligases involved in a novel pathway of chromosome maintenance. They enhance SUMO modification to many substrates in vivo, but also exhibit unique substrate specificity. PIAS proteins contain a specific RING finger known as Siz/PIAS (protein inhibitor of activated signal transducer and activator of transcription) RING (SP-RING) finger, which is essential for SUMO ligase activity. The SP-RING finger is a variant of the RING finger, which lacks the second, fifth, and sixth zinc-binding residues of the consensus C3H2C3-/C3HC4-type RING fingers. It binds a single Zn ion, instead of two ions bound by typical RING fingers.

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                ....*....|....*....|....*....|....*....|....*....|.
gi 21357563 210 LQCPICL----YPpvaAKLTRCGHAYCWPcLLHYLSLSDK--TWrKCPICY 254
Cdd:cd16650   2 LRCPLSLkrikTP---ARGKHCKHLQCFD-LDSYLEFNKRkpTW-KCPICD 47

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21357563 210 LQCPICLYP-PVAAKLTRCGHAYCWPCLLHYLSlSDKTWRkCPIC 253
Cdd:cd16749   1 LECPVCFEKlDVTAKVLPCQHTFCKPCLQRIFK-ARKELR-CPEC 43

RING finger, HC subclass, found in RING finger protein 19B (RNF19B) and similar proteins; RNF19B, also known as IBR domain-containing protein 3 or natural killer lytic-associated molecule (NKLAM), is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase that plays a role in controlling tumor dissemination and metastasis. It is involved in the cytolytic function of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). It interacts with ubiquitin conjugates UbcH7 and UbcH8, and ubiquitinates uridine kinase like-1 (URKL-1) protein, targeting it for degradation. Moreover, RNF19B is a novel component of macrophage phagosomes and plays a role in macrophage anti-bacterial activity. It functions as a novel modulator of macrophage inducible nitric oxide synthase (iNOS) expression. RNF19B contains an RBR domain followed by three TMs. The RBR domain was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 21357563 209 ELQCPICLYPPVAA---KLTRCGHAYCWPCLLHYLSLSDKTWR---KCPICYDAIHAGDLK 263
Cdd:cd16776   1 LVECPLCLVRQPPEnfpRLLSCSHRSCRDCLRQYLRIEITESRvniACPECSERLAPNDVR 61

Modified RING finger, HC subclass (C3HC3D-type), found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also known as RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), form the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta, but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to the RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has an RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction. This model corresponds to the RING domain, a modified C3HC3D-type RING-HC finger required for RBR-mediated ubiquitination.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21357563 204 IQTTEELQCPIC---LYPPVAAKLTRCGHAYCWPCLLHYLSLSDKTWRKCP 251
Cdd:cd16633   2 VPNQEPFECPICfddVPPGEGVVLRECLHSFCRECLRGAIQNSEEAEVKCP 52