DWNN domain; DWNN is a ubiquitin like domain found at the N terminus of the RBBP6 family of splicing-associated proteins. The DWNN domain is independently expressed in higher vertebrates so it may function as a novel ubiquitin-like modifier of other proteins.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 386768546    3 VHYKFKSTLNFDTITFDGLHISVGDLKREIVQQKRLGKIIDFDLQITNAQSKEEYKDDGFLIPKNTTLIISRIP 76
Cdd:pfam08783   1 VYYKFKSQKDYSRITFDGTGISVFDLKREIILQKKLGKGTDFDLLIYNAQTNEEYKDDTTLIPRNTSVIVRRVP 74

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 386768546  215 LICGICRDiFVDAVMIPCCGSSFCDDCVRTSLleSEDSECPDCKEKNcSPGSLIPNRFLRNSVNAFKNETGYNKSAAK-- 292
Cdd:TIGR00599  27 LRCHICKD-FFDVPVLTSCSHTFCSLCIRRCL--SNQPKCPLCRAED-QESKLRSNWLVSEIVESFKNLRPSLLEFLRip 102

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386768546  293 -PAAVKNEEKPPVEKEVEKKPVAEVEPEETEVKPEKQKESETNgsnppkSESPEPPATTEPSQKEKDKYDSDYEDnitiK 371
Cdd:TIGR00599 103 kTTPVENPDLAGPENSSKIELIEESESDGVDAEDEDLQRSATS------SRALAARSTADILQLSSDPSKRNDAD----Y 172

                  ....*..
gi 386768546  372 MPQPAAD 378
Cdd:TIGR00599 173 RSEPPNE 179

DWNN domain; DWNN is a ubiquitin like domain found at the N terminus of the RBBP6 family of splicing-associated proteins. The DWNN domain is independently expressed in higher vertebrates so it may function as a novel ubiquitin-like modifier of other proteins.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 386768546    3 VHYKFKSTLNFDTITFDGLHISVGDLKREIVQQKRLGKIIDFDLQITNAQSKEEYKDDGFLIPKNTTLIISRIP 76
Cdd:pfam08783   1 VYYKFKSQKDYSRITFDGTGISVFDLKREIILQKKLGKGTDFDLLIYNAQTNEEYKDDTTLIPRNTSVIVRRVP 74

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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVRTSLLESEDSE--CPDCKEKNCSPGSLIPNRFLRNSVN 278
Cdd:cd16597    4 EELTCSICLELFKDPVTLP-CGHNFCGVCIEKTWDSQHGSEysCPQCRATFPRRPELHKNTVLRNIVE 70

RING finger, HC subclass, found in tripartite motif-containing proteins, TRIM7, TRIM11 and TRIM27, and similar proteins; TRIM7, TRIM11 and TRIM27, 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, Bbox2, and a coiled coil region, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) by mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. TRIM11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM27, also known as RING finger protein 76 (RNF76), RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. In addition, it inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. TRIM27 promotes a non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. TRIM27 also forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is a component of an estrogen receptor 1 (ESR1) regulatory complex that is involved in estrogen receptor-mediated transcription in MCF-7 cells.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVRTSLLESE-DSECPDCKEkNCSPGSLIPNR 271
Cdd:cd16594    4 EELTCPICLDYFTDPVTLD-CGHSFCRACIARCWEEPEtSASCPQCRE-TCPQRNLRPNR 61

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVRTSLLESEDS--ECPDCKEKNCSPGSLI 268
Cdd:cd16609    2 EELTCSICLGLYQDPVTLP-CQHSFCRACIEDHWRQKDEGsfSCPECRAPFPEGPTLE 58

RING finger, HC subclass, found in checkpoint with forkhead and RING finger domains protein (CHFR); CHFR, also known as RING finger protein 196 (RNF196), is a checkpoint protein that delays entry into mitosis in response to stress. It functions as an E3 ubiquitin ligase that ubiquitinates and degrades its target proteins, such as Aurora-A, Plk1, Kif22, and PARP-1, which are critical for proper mitotic transitions. It also plays an important role in cell cycle progression and tumor suppression, and is negatively regulated by SUMOylation-mediated proteasomal ubiquitylation. Moreover, CHFR is involved in the early stage of the DNA damage response, which mediates the crosstalk between ubiquitination and poly-ADP-ribosylation. CHFR contains a fork head associated (FHA) domain and a C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 386768546 213 EDLICGICRDIFVDAVMIPCCGSSFCDDCVrTSLLESEDSECPDCKEK 260
Cdd:cd16503    1 ENLTCSICQDLLHDCVSLQPCMHNFCAACY-SDWMERSNTECPTCRAT 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
                 ....*....|....*....|....*....|....*....|....*...
gi 386768546 213 EDLICGICRDIFVDAVMIPCcGSSFCDDCVRTSLLESEDSECPDCKEK 260
Cdd:cd16568    3 ETQECIICHEYLYEPMVTTC-GHTYCYTCLNTWFKSNRSLSCPDCRTK 49

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 386768546 213 EDLICGICRDIFVDAVMIPCCGSSFCDDCVRTsLLESEDSECPDCKE 259
Cdd:cd16544    1 AELTCPVCQEVLKDPVELPPCRHIFCKACILL-ALRSSGARCPLCRG 46

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 386768546   217 CGICRDIFVDAVMIPCCGSSFCDDCVRTsLLESEDSECPDC 257
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRK-WLESGNNTCPIC 40

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 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVRTSLLESEDSECPDCK 258
Cdd:cd16608    5 DELLCSICLSIYQDPVSLG-CEHYFCRQCITEHWSRSEHRDCPECR 49

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 386768546 210 EIPEDLICGICRDIFVDAVMIPCcGSSFCDDCV----RTSLLESEDSECPDCKEKNcSPGSLIPNRFLRNSV 277
Cdd:cd16591    2 NIKEEVTCPICLELLTEPLSLDC-GHSFCQACItanhKESVNQEGESSCPVCRTSY-QPENLRPNRHLANIV 71

RING finger, HC subclass, found in really interesting new gene 1 protein (RING1) and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), was identified as a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. It is a core component of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase that 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. RING1 interacts with multiple PcG proteins and displays tumorigenic activity. It also shows zinc-dependent DNA binding activity. Moreover, RING1 inhibits transactivation of the DNA-binding protein recombination signal binding protein-Jkappa (RBP-J) by Notch through interaction with the LIM domains of KyoT2. RING1 contains a C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 386768546 214 DLICGICRDIFVDAVMIPCCGSSFCDDCVRTSlLESEDSECPDCKEKNCSPGSLIPN 270
Cdd:cd16739    3 ELMCPICLDMLKNTMTTKECLHRFCSDCIVTA-LRSGNKECPTCRKKLVSKRSLRPD 58

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM43, TRIM48, TRIM49, TRIM51, TRIM64 and similar proteins; The family includes a group of closely related uncharacterized tripartite motif-containing proteins, TRIM43, TRIM43B, TRIM48/RNF101, TRIM49/RNF18, TRIM49B, TRIM49C/TRIM49L2, TRIM49D/TRIM49L, TRIM51/SPRYD5, TRIM64, TRIM64B, and TRIM64C, whose biological function remain unclear. TRIM49, also known as testis-specific RING-finger protein, has moderate similarity with SS-A/Ro52 antigen, suggesting it may be one of the target proteins of autoantibodies in the sera of patients with these autoimmune disorders. All family members 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 as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. In RBCC region, they all have a C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 386768546 214 DLICGICRDIFVDAVMIpCCGSSFCDDCVrtsLLESEDS----ECPDCKE 259
Cdd:cd16603    4 ELTCPICMNYFIDPVTI-DCGHSFCRPCL---YLNWQDIpflaQCPECRK 49

Modified RING finger, HC subclass (C4C4-type), found in tripartite motif-containing protein 37 (TRIM37) and similar proteins; TRIM37, also known as mulibrey nanism protein, or MUL, is a peroxisomal E3 ubiquitin-protein ligase that is involved in the tumorigenesis of several cancer types, including pancreatic ductal adenocarcinoma (PDAC), hepatocellular carcinoma (HCC), breast cancer, and sporadic fibrothecoma. It mono-ubiquitinates histone H2A, a chromatin modification associated with transcriptional repression. Moreover, TRIM37 possesses anti-HIV-1 activity, and interferes with viral DNA synthesis. Mutations in the human TRIM37 gene (also known as MUL) cause Mulibrey (muscle-liver-brain-eye) nanism, a rare growth disorder of prenatal onset characterized by dysmorphic features, pericardial constriction, and hepatomegaly. TRIM37 belongs to the C-VIII 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 C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a MATH (meprin and TRAF-C homology) domain positioned C-terminal to the RBCC domain. Its MATH domain has been shown to interact with the TRAF (TNF-Receptor-Associated Factor) domain of six known TRAFs in vitro.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 386768546 215 LICGICRDIFVDAVMIPCCGSSFCDDCVRTSLLESEdSECPDC 257
Cdd:cd16619    1 FRCFICMEKLRDPRLCPHCSKLFCKGCIRRWLSEQR-SSCPHC 42

Zinc knuckle; This is a zinc-binding domain of the form CxxCxxxGHxxxxC from a variety of different species.

                          10        20
                  ....*....|....*....|
gi 386768546  148 PASYRCNKCKKSGHWIKNCP 167
Cdd:pfam13696   1 PPGYVCHICGKKGHYIQDCP 20

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
                 ....*....|....*....|....*....|....*....|....*
gi 386768546 217 CGICRDIFVDAVMIPcCGSSFCDDCVRTSLLesedSECPDCKEKN 261
Cdd:cd16513    5 CPLCRGLLFEPVTLP-CGHTFCKRCLERDPS----SRCRLCRLKL 44

RING finger, HC subclass, found in Saccharomyces cerevisiae radiation sensitivity protein 18 (RAD18) and similar proteins; RAD18, also called RING-type E3 ubiquitin transferase RAD18, acts as a postreplication repair E3 ubiquitin-protein ligase that associates with the E2 ubiquitin conjugating enzyme UBC2/RAD6 to form the UBC2-RAD18 ubiquitin ligase complex involved in postreplicative repair (PRR) of damaged DNA. The UBC2-RAD18 complex cooperates with RAD5 and the UBC13-MMS2 dimer to attach mono-ubiquitin chains on 'Lys-164' of POL30, which is necessary for PRR. The UBC2-RAD18 complex is also involved in prevention of spontaneous mutations caused by 7,8-dihydro-8-oxoguanine. RAD18 is an E3 RING-finger protein belonging to the UBC2/RAD6 epistasis group. It contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 386768546 217 CGICRDiFVDAVMIPCCGSSFCDDCVRTSLleSEDSECPDCK 258
Cdd:cd23148    6 CHICKD-LLKAPMRTPCNHTFCSFCIRTHL--NNDARCPLCK 44

RING finger, HC subclass, found in Ret finger protein-like 4B (RFPL4B) and similar proteins; RFPL4B, also called RING finger protein 211 (RNF211), is an uncharacterized RING finger protein containing a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 386768546 213 EDLICGICRDIFVDAVMIPCcGSSFCDDCVRTSLLESEDSE--CPDCKEKNCSP 264
Cdd:cd16623    7 MEATCPICLDFFSHPISLSC-AHIFCFDCIQKWMTKREDSIltCPLCRKEQKKP 59

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        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVrTSLLESEDSECPDCKEKNCSpGSLIPNRFLRNSVNAFK 281
Cdd:cd16596    8 EEVTCPICLDPFVEPVSIE-CGHSFCQECI-SQVGKGGGSVCPVCRQRFLL-KNLRPNRQLANMVNNLK 73

RING finger (Really Interesting New Gene) domain and U-box domain superfamily; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers: some have different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enable efficient transfer of ubiquitin from E2 to the substrates.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 386768546 217 CGICRDIFVDA--VMIPCCGSSFCDDCVrTSLLESEDSECPDC 257
Cdd:cd00162    1 CPICREEMNDRrpVVLLSCGHTFSRSAI-ARWLEGSKQKCPFC 42

RING finger, HC subclass, found in tripartite motif-containing protein 8 (TRIM8) and similar proteins; TRIM8, also known as glioblastoma-expressed RING finger protein (GERP) or RING finger protein 27 (RNF27), is a probable E3 ubiquitin-protein ligase that may promote proteasomal degradation of suppressor of cytokine signaling 1 (SOCS1) and further regulate interferon-gamma signaling. It functions as a new p53 modulator that stabilizes p53 impairing its association with MDM2 and inducing the reduction of cell proliferation. TRIM8 deficit dramatically impairs p53 stabilization and activation in response to chemotherapeutic drugs. TRIM8 also modulates tumor necrosis factor-alpha (TNFalpha) and interleukin-1beta (IL-1beta)-triggered nuclear factor-kappaB (NF- kappa B) activation by targeting transforming growth factor beta (TGFbeta) activated kinase 1 (TAK1) for K63-linked polyubiquitination. Moreover, TRIM8 modulates translocation of phosphorylated STAT3 into the nucleus through interaction with Hsp90beta and consequently regulates transcription of Nanog in embryonic stem cells. It also interacts with protein inhibitor of activated STAT3 (PIAS3), which inhibits IL-6-dependent activation of STAT3. TRIM8 belongs to the C-V 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 domain, as well as an uncharacterized region positioned C-terminal to the RBCC domain. The coiled coil domain is required for homodimerization and the region immediately C-terminal to the RING motif is sufficient to mediate the interaction with SOCS1.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVRTSLL-ESEDSECPDC 257
Cdd:cd16580   10 EELICPICLHVFVEPVQLP-CKHNFCRGCIGEAWAkDAGLVRCPEC 54

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 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVRTSLLESEDS-----ECPDCK 258
Cdd:cd16581    1 EELTCSICYNIFDDPKILP-CSHTFCKNCLEKLLAASGYYllaslKCPTCR 50

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 386768546 214 DLICGICRDIFVDAVMIPCCGSSFCDDCVRTSLLESEdSECPDCKEKNCSPGSLIP 269
Cdd:cd16531    1 ELMCPICLGIIKNTMTVKECLHRFCAECIEKALRLGN-KECPTCRKHLPSRRSLRP 55

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 386768546 216 ICGICRDIFVDAVMIPCCGSSFCDDCVRTSLleSEDSECPDCKE 259
Cdd:cd16506    2 TCPICLDEIQNKKTLEKCKHSFCEDCIDRAL--QVKPVCPVCGV 43

RING finger, HC subclass, found in Mus musculus tripartite motif-containing protein 43 (TRIM43) and similar propteins; This subfamily includes TRIM43A, TRIM43B and TRIM43C, which are expressed specifically in mouse preimplantation embryos. They contain a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVrtsLLESED----SECPDCKE 259
Cdd:cd23133    2 ETLTCSICQGIFMNPVYLR-CGHKFCEACL---LLFQEDikfpAYCPMCRQ 48

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein RNFT1, RNFT2, and similar proteins; Both RNFT1 and RNFT2 are multi-pass membrane proteins containing a C3HC4-type RING-HC finger. Their biological roles remain unclear.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|...
gi 386768546 216 ICGICRDIFVDAVMIPcCGSSFCDDCVrTSLLESEDSeCPDCK 258
Cdd:cd16532    2 ICPICQDEFKDPVVLR-CKHIFCEDCV-SEWFERERT-CPLCR 41

RING finger, HC subclass, found in RING finger protein 166 (RNF166) and similar proteins; RNF166 is encoded by the gene RNF166 targeted by thyroid hormone receptor alpha1 (TRalpha1), which is important in brain development. It plays an important role in RNA virus-induced interferon-beta production by enhancing the ubiquitination of TRAF3 and TRAF6. RNF166, together with three closely related proteins: RNF114, RNF125 and RNF138, 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 386768546 215 LICGICRDIFVDAVMIPCCGSSFCDDCVRTSlLESEDSECPDCK 258
Cdd:cd16549    2 FSCPICLEVYHKPVVITSCGHTFCGECLQPC-LQVASPLCPLCR 44

RING finger, HC subclass, found in tripartite motif-containing protein 39 (TRIM39) and similar proteins; TRIM39, also known as RING finger protein 23 (RNF23) or testis-abundant finger protein, is an E3 ubiquitin-protein ligase that plays a role in controlling DNA damage-induced apoptosis through inhibition of the anaphase promoting complex (APC/C), a multiprotein ubiquitin ligase that controls multiple cell cycle regulators, including cyclins, geminin, and others. TRIM39 also functions as a regulator of several key processes in the proliferative cycle. It directly regulates p53 stability. It modulates cell cycle progression and DNA damage responses via stabilizing p21. Moreover, TRIM39 negatively regulates the nuclear factor kappaB (NFkappaB)-mediated signaling pathway through stabilization of Cactin, an inhibitor of NFkappaB- and Toll-like receptor (TLR)-mediated transcription, which is induced by inflammatory stimulants such as tumor necrosis factor alpha. Furthermore, TRIM39 is a MOAP-1-binding protein that can promote apoptosis signaling through stabilization of MOAP-1 via the inhibition of its poly-ubiquitination process. TRIM39 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 386768546 217 CGICRDIFVDAVMIPCcGSSFCDDCVRTSLLESE-DSECPDC 257
Cdd:cd16601    4 CSLCKEYLKDPVIIEC-GHNFCRACITRFWEELDgDFPCPQC 44

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM41, TRIM52 and similar proteins; TRIM41 and TRIM52, two closely related tripartite motif-containing proteins, have dramatically expanded RING domains compared with the rest of the TRIM family proteins. TRIM41 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. In contrast, TRIM52 lacks the putative viral recognition SPRY/B30.2 domain, and thus has been classified to the C-V subclass of the TRIM family that contains only RBCC domains. TRIM41, also known as RING finger-interacting protein with C kinase (RINCK), is an E3 ubiquitin-protein ligase that promotes the ubiquitination of protein kinase C (PKC) isozymes in cells. It specifically recognizes the C1 domain of PKC isozymes. It controls the amplitude of PKC signaling by controlling the amount of PKC in the cell. TRIM52, also known as RING finger protein 102 (RNF102), is encoded by a novel, noncanonical antiviral TRIM52 gene in primate genomes with unique specificity determined by the rapidly evolving RING domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 386768546 213 EDLICGICRDIFVDAVMIPcCGSSFCDDCVrTSLLeseDSECPDCKE 259
Cdd:cd16602    2 EEAVCAICLDYFKDPVSIG-CGHNFCRVCV-TQLW---GFTCPQCRK 43

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 386768546 215 LICGICRDIFVDAVMIPcCGSSFCDDCVRtSLLESEDS---ECPDCKE 259
Cdd:cd16604    1 LSCPICLDLLKDPVTLP-CGHSFCMGCLG-ALWGAGRGgraSCPLCRQ 46

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM60, TRIM61, TRIM75 and similar proteins; TRIM60, also known as RING finger protein 129 (RNF129) or RING finger protein 33 (RNF33), is a cytoplasmic protein expressed in the testis. It may play an important role in the spermatogenesis process, the development of the preimplantation embryo, and in testicular functions. RNF33 interacts with the cytoplasmic kinesin motor proteins KIF3A and KIF3B suggesting possible contribution to cargo movement along the microtubule in the expressed sites. It is also involved in spermatogenesis in Sertoli cells under the regulation of nuclear factor-kappaB (NF-kappaB). TRIM75 mainly localizes within spindles, suggesting it may function in spindle organization and thereby affect meiosis. Both TRIM60 and TRIM75 belong 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 B2-box, and two coiled coil domains, as well as a PRY domain and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. In contrast, TRIM61 belongs to the C-V subclass of the TRIM family that contains RBCC domains only. Its biological function remains unclear.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 386768546 216 ICGICRDIFVDAVMIpCCGSSFCDDCVRTSLLESEDS-ECPDCK 258
Cdd:cd16607    3 SCPICLDYLKDPVTI-NCGHNFCRSCISMSWKDLQDTfPCPVCR 45

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        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386768546 215 LICGICRDIFVDAVMIPCcGSSFCDDCVrTSLLESEDSE--CPDCKeKNCSPGSLIPN-RF------LRNSVNAFKNETG 285
Cdd:cd16498   17 LECPICLELLKEPVSTKC-DHQFCRFCI-LKLLQKKKKPapCPLCK-KSVTKRSLQEStRFkqlveaVKKLIDAFELDTG 93

                 .
gi 386768546 286 Y 286
Cdd:cd16498   94 L 94

RING finger, HC subclass, found in RNA-binding proteins of the evolutionarily-conserved MEX-3 family; MEX-3 phosphoproteins are found in vertebrates. They are mediators of post-transcriptional regulation in different organisms, and have been implicated in many core biological processes, including embryonic development, epithelial homeostasis, immune responses, metabolism, and cancer. They contain two K homology (KH) domains that provide RNA-binding capacity, and a C-terminal C3HC4-type RING-HC finger. They shuttle between the nucleus and the cytoplasm via the CRM1-dependent export pathway. The RNA-binding protein MEX-3 from nematode Caenorhabditis elegans is the founding member of the MEX-3 family. Due to the lack of a RING-HC finger, it is not included here.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|.
gi 386768546 217 CGICRDIFVDAVMIPCCGSSFCDDCVrTSLLESEDSECPDC 257
Cdd:cd16518    3 CVVCFESEVVAALVPCGHNLFCMECA-NRICEKSDPECPVC 42

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
                 ....*....|....*....|....*....|....*....|....*.
gi 386768546 213 EDLICGICRDIFVDAVMIPCcGSSFCDDCVRTSLLESEDSECPDCK 258
Cdd:cd23132    1 EEFLCCICLDLLYKPVVLEC-GHVFCFWCVHRCMNGYDESHCPLCR 45

RING finger found in polycomb group RING finger protein 5 (PCGF5) and similar proteins; PCGF5, also known as RING finger protein 159 (RNF159), is one of six PcG RING finger (PCGF) homologs (PCGF1/NSPc1, PCGF2/Mel-18, PCGF3, PCGF4/BMI1, PCGF5, and PCGF6/MBLR) and serves as the core component of a Polycomb repressive complex 1 (PRC1). Like other PCGF homologs, PCGF5 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. PCGF5 contains a C3HC4-type RING-HC finger.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 386768546 215 LICGICRDIFVDAVMIPCCGSSFCDDCVRTSLLESEDseCPDCKeknCSPGSLIPNRFLR 274
Cdd:cd16737   11 ITCRICKGYLIKPTTVTECLHTFCKSCIVQHFEDSND--CPECG---IQVHETNPLEMLR 65