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        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720413268   3 ETLTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSS-LCPTCRCPVERICKNH 56
Cdd:cd16503     1 ENLTCSICQDLLHDCVSLQPCMHNFCAACYSDWMERSNtECPTCRATVQRVNKNH 55

PBZ domain; This domain is a zinc-finger motif that in humans is part of the APLF, aprataxin- and PNK-like forkhead association domain-containing protein. The ZnF is highly conserved both in primary sequence and in the spacing between the putative zinc coordinating residues and is configured CX5CX6HX5H. Many of the proteins containing the APLF-like ZnF are involved in DNA strand break repair and/or contain domains implicated in DNA metabolism.

                          10        20
                  ....*....|....*....|....
gi 1720413268 336 RPDCYWGRNCRTQvKAHHAMKFNH 359
Cdd:pfam10283   1 RPPCKYGAKCYRK-NPQHFKEFSH 23

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        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720413268   3 ETLTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSS-LCPTCRCPVERICKNH 56
Cdd:cd16503     1 ENLTCSICQDLLHDCVSLQPCMHNFCAACYSDWMERSNtECPTCRATVQRVNKNH 55

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1720413268   6 TCIICQDLL--HDCVSLQPCMHTFCAACYSGWMERSSLCPTCR 46
Cdd:pfam13639   2 ECPICLEEFeeGDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

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 1720413268    7 CIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSL-CPTC 45
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWLESGNNtCPIC 40

PBZ domain; This domain is a zinc-finger motif that in humans is part of the APLF, aprataxin- and PNK-like forkhead association domain-containing protein. The ZnF is highly conserved both in primary sequence and in the spacing between the putative zinc coordinating residues and is configured CX5CX6HX5H. Many of the proteins containing the APLF-like ZnF are involved in DNA strand break repair and/or contain domains implicated in DNA metabolism.

                          10        20
                  ....*....|....*....|....
gi 1720413268 336 RPDCYWGRNCRTQvKAHHAMKFNH 359
Cdd:pfam10283   1 RPPCKYGAKCYRK-NPQHFKEFSH 23

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        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1720413268   3 ETLTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSS-LCPTCRCPVERICKNH 56
Cdd:cd16503     1 ENLTCSICQDLLHDCVSLQPCMHNFCAACYSDWMERSNtECPTCRATVQRVNKNH 55

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 1720413268   1 MEETLTCIICQDLLHDCVsLQPCMHTFCAACYSGWMERSSLCPTCRCPVE--RICKNHILNNLVEAYliqhpdksrseed 78
Cdd:TIGR00599  23 LDTSLRCHICKDFFDVPV-LTSCSHTFCSLCIRRCLSNQPKCPLCRAEDQesKLRSNWLVSEIVESF------------- 88

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720413268  79 vrsMDARNKITQDMLQPKVRRSFSD-----EEGSSEDLLELSDVDSESSDISQPYIVCRQCpeyRRQAVQSLPCPVPESe 153
Cdd:TIGR00599  89 ---KNLRPSLLEFLRIPKTTPVENPdlagpENSSKIELIEESESDGVDAEDEDLQRSATSS---RALAARSTADILQLS- 161

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1720413268 154 lgatlalggeapstSASLPTAAPDYMC-PLQGSHAICTCCFQPMPDRRAEREQD 206
Cdd:TIGR00599 162 --------------SDPSKRNDADYRSePPNEGLVQCPICQQRMPEKAVERHLD 201

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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720413268   1 MEETLTCIICQDLLHDCVSLqPCMHTFCAACYSG-WME---RSSLCPTCRCPVER---ICKNHILNNLVE 63
Cdd:cd16597     2 LEEELTCSICLELFKDPVTL-PCGHNFCGVCIEKtWDSqhgSEYSCPQCRATFPRrpeLHKNTVLRNIVE 70

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 1720413268   3 ETLTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSL-CPTCRCPV 49
Cdd:cd16544     1 AELTCPVCQEVLKDPVELPPCRHIFCKACILLALRSSGArCPLCRGPV 48

RING finger, HC subclass, found in tripartite motif-containing protein 35 (TRIM35) and similar proteins; TRIM35, also known as hemopoietic lineage switch protein 5 (HLS5), is a putative hepatocellular carcinoma (HCC) suppressor that inhibits phosphorylation of pyruvate kinase isoform M2 (PKM2), which is involved in aerobic glycolysis of cancer cells and further suppresses the Warburg effect and tumorigenicity in HCC. It also negatively regulates Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon production by suppressing the stability of interferon regulatory factor 7 (IRF7). Moreover, TRIM35 regulates erythroid differentiation by modulating globin transcription factor 1 (GATA-1) activity. TRIM35 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 1720413268   2 EETLTCIICQDLLHDCVSLqPCMHTFCAACYSGWMER--SSLCPTCR--CPVERICKNHILNNLVE 63
Cdd:cd16599     2 KEELLCPICYEPFREAVTL-RCGHNFCKGCVSRSWERqpRAPCPVCKeaSSSDDLRTNHTLNNLVE 66

Zinc finger, C3HC4 type (RING finger);

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 1720413268   7 CIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSLCPTC 45
Cdd:pfam13923   2 CPICMDMLKDPSTTTPCGHVFCQDCILRALRAGNECPLC 40

RING-finger-containing E3 ubiquitin ligase [Signal transduction mechanisms];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720413268   1 MEETLTCIICQDLLHDCVsLQPCMHTFCAACYSGWMERSSLCPTCRCPVE--RICKNHILNNLVEAYLIQHPdksrSEED 78
Cdd:COG5432    22 LDSMLRCRICDCRISIPC-ETTCGHTFCSLCIRRHLGTQPFCPVCREDPCesRLRGSSGSREINESHARNRD----LLRK 96

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1720413268  79 VRSMDARNKITQDMLQPKVRRSFSDEEGSSEDlleLSDVDSESSDISQPYIVCRQCPE-YRRQAVQSLPCP-----VP-- 150
Cdd:COG5432    97 VLESLCRLPRPIKEERPCRWETVIAQDSASGD---EEWEDDLASNSSPASIAKKTSRDsKKRKREDLVHCPacsnlVPhn 173

                         170       180
                  ....*....|....*....|....*
gi 1720413268 151 --ESELGATLALGGEAPSTSASLPT 173
Cdd:COG5432   174 qiNQHLDSCLNSPSSPSSSSSPYKN 198

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 1720413268   6 TCIICQDLLHDCVSLqPCMHTFCAACYSGWMERSSLCPTCR 46
Cdd:cd16532     2 ICPICQDEFKDPVVL-RCKHIFCEDCVSEWFERERTCPLCR 41

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 1720413268   1 MEETLTCIICQDLLHDCVSLqPCMHTFCAACYSGWM--ERSSLCPTCRCPVERI 52
Cdd:cd16568     1 ILETQECIICHEYLYEPMVT-TCGHTYCYTCLNTWFksNRSLSCPDCRTKITTQ 53

HC subclass of RING (RING-HC) finger and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers. Some have a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle, and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1720413268   5 LTCIICQDLLHDCVSLqPCMHTFCAACYSGWME-RSSLCPTC 45
Cdd:cd16449     1 LECPICLERLKDPVLL-PCGHVFCRECIRRLLEsGSIKCPIC 41

RING finger, HC subclass, found in topoisomerase I-binding arginine/serine-rich protein (Topors) and similar proteins; Topors, also known as topoisomerase I-binding RING finger protein, tumor suppressor p53- binding protein 3, or p53-binding protein 3 (p53BP3), is a ubiquitously expressed nuclear E3 ubiquitin-protein ligase that can ligate both ubiquitin and small ubiquitin-like modifier (SUMO) to substrate proteins in the nucleus. It contains an N-terminal C3HC4-type RING-HC finger which ligates ubiquitin to its target proteins including DNA topoisomerase I, p53, NKX3.1, H2AX, and the AAV-2 Rep78/68 proteins. As a RING-dependent E3 ubiquitin ligase, Topors works with the E2 enzymes UbcH5a, UbcH5c, and UbcH6, but not with UbcH7, CDC34, or UbcH2b. Topors acts as a tumor suppressor in various malignancies. It regulates p53 modification, suggesting it may be responsible for astrocyte elevated gene-1 (AEG-1, also known as metadherin, or LYRIC) ubiquitin modification. Plk1-mediated phosphorylation of Topors inhibits Topors-mediated sumoylation of p53, whereas p53 ubiquitination is enhanced, leading to p53 degradation. It also functions as a negative regulator of the prostate tumor suppressor NKX3.1. Moreover, Topors is associated with promyelocytic leukemia nuclear bodies, and may be involved in the cellular response to camptothecin. It also plays a key role in the turnover of H2AX protein, discriminating the type of DNA damaging stress. Furthermore, Topors is a cilia-centrosomal protein associated with autosomal dominant retinal degeneration. Mutations in TOPORS cause autosomal dominant retinitis pigmentosa (adRP).

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1720413268   6 TCIICQDLLHDCVS-LQPCMHTFCAACYSGWMERSSLCPTCRCP 48
Cdd:cd16574     3 SCPICLDRFENEKAfLDGCFHAFCFTCILEWSKVKNECPLCKQP 46

RING finger, HC subclass, found in polycomb group RING finger protein 1 (PCGF1) and similar proteins; PCGF1, also known as nervous system Polycomb-1 (NSPc1) or RING finger protein 68 (RNF68), 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 noncanonical Polycomb repressive complex 1 (PRC1)-like BCOR complex that also contains RING1, RNF2, RYBP, SKP1, as well as the BCL6 co-repressor BCOR and the histone demethylase KDM2B, and is required to maintain the transcriptionally repressive state of some genes, such as Hox genes, BCL6 and the cyclin-dependent kinase inhibitor, CDKN1A. PCGF1 promotes cell cycle progression and enhances cell proliferation as well. It is a cell growth regulator that acts as a transcriptional repressor of p21Waf1/Cip1 via the retinoid acid response element (RARE element). Moreover, PCGF1 functions as an epigenetic regulator involved in hematopoietic cell differentiation. It cooperates with the transcription factor runt-related transcription factor 1 (Runx1) in regulating differentiation and self-renewal of hematopoietic cells. Furthermore, PCGF1 represents a physical and functional link between Polycomb function and pluripotency. PCGF1 contains a C3HC4-type RING-HC finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1720413268   1 MEETLTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSLCPTC 45
Cdd:cd16733     6 LNEHIVCYLCAGYFIDATTITECLHTFCKSCIVKYLQTSKYCPMC 50

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
                  ....*....|....*....|....*....|....*....
gi 1720413268   5 LTCIICQDLLHDCVsLQPCMHTFCAACYSGWMERSSLCP 43
Cdd:cd16637     2 LTCHICLQPLVEPL-DTPCGHTFCYKCLTNYLKIQQCCP 39

RING finger, HC subclass, found in postreplication repair protein RAD18 and similar proteins; RAD18, also known as HR18 or RING finger protein 73 (RNF73), is an E3 ubiquitin-protein ligase involved in post replication repair of UV-damaged DNA via its recruitment to stalled replication forks. It associates to the E2 ubiquitin conjugating enzyme UBE2B to form the UBE2B-RAD18 ubiquitin ligase complex involved in mono-ubiquitination of DNA-associated PCNA on K164. It also interacts with another E2 ubiquitin conjugating enzyme RAD6 to form a complex that monoubiquitinates proliferating cell nuclear antigen at stalled replication forks in DNA translesion synthesis. Moreover, Rad18 is a key factor in double-strand break DNA damage response (DDR) pathways via its association with K63-linked polyubiquitylated chromatin proteins. It can function as a mediator for DNA damage response signals to activate the G2/M checkpoint in order to maintain genome integrity and cell survival after ionizing radiation (IR) exposure. RAD18 contains a C3HC4-type RING-HC finger, a ubiquitin-binding zinc finger domain (UBZ), a SAP (SAF-A/B, Acinus and PIAS) domain, and a RAD6-binding domain (R6BD).

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1720413268   1 MEETLTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSLCPTCRCPV 49
Cdd:cd16529     1 LDDLLRCPICFEYFNTAMMITQCSHNYCSLCIRRFLSYKTQCPTCRAAV 49

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1720413268   6 TCIICQDLLHDCVSLqPCMHTFCAACYSGWMERSSL-CPTCR 46
Cdd:cd16550     2 LCPICLEILVEPVTL-PCNHTLCMPCFQSTVEKASLcCPLCR 42

RING finger, H2 subclass, found in DAZ (deleted in azoospermia)-interacting protein 3 (DZIP3) and similar proteins; DZIP3, also known as RNA-binding ubiquitin ligase of 138 kDa (RUL138) or 2A-HUB protein, is an RNA-binding E3 ubiquitin-protein ligase that interacts with coactivator-associated arginine methyltransferase 1 (CARM1) and acts as a transcriptional coactivator of estrogen receptor (ER) alpha. It is also a histone H2A ubiquitin ligase that catalyzes monoubiquitination of H2A at lysine 119, functioning as a combinatorial component of the repression machinery required for repressing a specific chemokine gene expression program, critically modulating migratory responses to Toll-like receptors (TLR) activation. DZIP3 contains a C3H2C3-type RING-H2 finger at the C-terminus.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1720413268   7 CIICQDLLHDCVSLQ--PCMHTFCAACYSGWMERSSLCPTCRCPV 49
Cdd:cd16460     3 CVICHEAFSDGDRLLvlPCAHKFHTQCIGPWLDGQQTCPTCRLHV 47

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 1720413268   7 CIICQDLLHDCVSLQ--PCMHTFCAACYSGWMERSSLCPTCRCPVE 50
Cdd:cd16682    10 CTICLSMLEDGEDVRrlPCMHLFHQLCVDQWLAMSKKCPICRVDIE 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 1720413268   6 TCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSLCPTCRC 47
Cdd:cd16506     2 TCPICLDEIQNKKTLEKCKHSFCEDCIDRALQVKPVCPVCGV 43

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.

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                  ....*....|....*....|....*....|....*....|....*..
gi 1720413268   5 LTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSLCPTCRCPVER 51
Cdd:cd16734    15 LMCALCGGYFIDAATIVECLHSFCKTCIVRYLETNKYCPMCDVQVHK 61

RING finger found in polycomb group RING finger protein 4 (PCGF4) and similar proteins; PCGF4, also known as polycomb complex protein BMI-1 (B cell-specific Moloney murine leukemia virus integration site 1) or RING finger protein 51 (RNF51), 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), and plays important roles in chromatin compaction and H2AK119 monoubiquitination. PCGF4 associates with the Runx1/CBFbeta transcription factor complex to silence target genes in a PRC2-independent manner. Moreover, PCGF4 is expressed in the hair cells and supporting cells. It can regulate cell survival by controlling mitochondrial function and reactive oxygen species (ROS) level in thymocytes and neurons, thus having an important role in the survival and sensitivity to ototoxic drug of auditory hair cells. Furthermore, PCGF4 controls memory CD4 T-cell survival through direct repression of Noxa gene in an Ink4a- and Arf-independent manner. It is required in neurons to suppress p53-induced apoptosis via regulating the antioxidant defensive response, and also involved in the tumorigenesis of various cancer types. PCGF4 contains a C3HC4-type RING-HC finger.

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                  ....*....|....*....|....*....|....*....|....*..
gi 1720413268   5 LTCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSLCPTCRCPVER 51
Cdd:cd16736    12 LMCVLCGGYFIDATTIIECLHSFCKTCIVRYLETSKYCPICDVQVHK 58

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 1720413268   1 MEETLTCIICQDLLHDCVSLQpCMHTFCAACYSGWMERS------SLCPTCRC--PVERICKNHILNNLVE 63
Cdd:cd16591     3 IKEEVTCPICLELLTEPLSLD-CGHSFCQACITANHKESvnqegeSSCPVCRTsyQPENLRPNRHLANIVE 72

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

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                  ....*....|....*....|....*....|....*....|
gi 1720413268   7 CIICQDLLHDCVSLqPCMHTFCAACYSGWMERSSLCPTCR 46
Cdd:cd16561     5 CSICLEDLNDPVKL-PCDHVFCEECIRQWLPGQMSCPLCR 43

RING finger, HC subclass, found in Dictyostelium discoideum Ras guanine nucleotide exchange factor O (RasGEFO) and similar proteins; RasGEFO, also known as RasGEF domain-containing protein O, functions as a Ras guanine-nucleotide exchange factor (RasGEFs), activating Ras by catalyzing the replacement of GDP with GTP. RasGEFs are particularly important for signaling in development and chemotaxis in many organisms, including Dictyostelium. RasGEFO contains a C3HC4-type RING-HC finger that may be responsible for E3 ubiquitin ligase activity.

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                  ....*....|....*....|....*....|....*....|....
gi 1720413268   6 TCIICQDLLHDCVSLQPCMHTFCAACYSGWMERSSlCPTCRCPV 49
Cdd:cd16507    11 TCGICQNLFKDPNTLIPCGHAFCLDCLTTNASIKN-CIQCKVEY 53

RING finger, H2 subclass, found in TRAF-interacting protein (TRAIP) and similar proteins; TRAIP, also known as RING finger protein 206 (RNF206) or TRIP, is a ubiquitously expressed nucleolar E3 ubiquitin ligase important for cellular proliferation and differentiation. It is found near mitotic chromosomes and functions as a regulator of the spindle assembly checkpoint. TRAIP interacts with tumor necrosis factor (TNF)-receptor-associated factor (TRAF) proteins and inhibits TNF-alpha-mediated nuclear factor (NF)-kappaB activation. It also interacts with two tumor suppressors CYLD and spleen tyrosine kinase (Syk), and DNA polymerase eta, which facilitates translesional synthesis after DNA damage. TRAIP contains an N-terminal C3H2C2-type RING-H2 finger and an extended coiled-coil domain.

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                  ....*....|....*....|....*....|....*....|..
gi 1720413268   7 CIICQDLLH--DCVSLQPCMHTFCAACYSGWMERSSLCPTCR 46
Cdd:cd16480     2 CTICSDFFDnsRDVAAIHCGHTFHYDCLLQWFDTSRTCPQCR 43

RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

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                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1720413268   1 MEETLTCIIC---------QDLLHDCVsLQPCMHTFCAACYSGWMERSSLCPTCRCP 48
Cdd:cd23117     1 ENGSVDCVICmsdielpstNSVRRDYM-VTPCNHIFHTNCLERWMDIKLECPTCRRP 56

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 1720413268   2 EETLTCIICQDLLHDCVSLqPCMHTFCAACYSGWMERSSL---------CPTCR 46
Cdd:cd16762     1 EEDLTCPICCCLFDDPRVL-PCSHNFCKKCLEGILEGNVRtmlwrppfkCPTCR 53

RING finger, HC subclass, found in tripartite motif-containing protein 59 (TRIM59) and similar proteins; 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. It is upregulated in gastric cancer and promotes gastric carcinogenesis by interacting with and targeting the P53 tumor suppressor for its ubiquitination and degradation. It also acts as a novel accessory molecule involved in cytotoxicity of BCG-activated macrophages (BAM). Moreover, TRIM59 may serve as a multifunctional regulator for innate immune signaling pathways. It interacts with ECSIT and negatively regulates nuclear factor-kappaB (NF- kappa B) and interferon regulatory factor (IRF)-3/7-mediated signal pathways. TRIM59 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, TRIM59 contains a C-terminal transmembrane domain.

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                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1720413268   2 EETLTCIICQDLLHDCVSLqPCMHTFCAACYSGWMERSS------------LCPTCR 46
Cdd:cd16763     1 EEDLTCSVCYSLFEDPRVL-PCSHTFCRNCLENILQVSGnfsiwrplrpplKCPNCR 56

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

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                  ....*....|....*....|....*....|....*....|....*...
gi 1720413268   5 LTCIICQDLLHDCVSLqPCMHTFCAACYSGWME----RSSLCPTCRCP 48
Cdd:cd16604     1 LSCPICLDLLKDPVTL-PCGHSFCMGCLGALWGagrgGRASCPLCRQT 47

RING finger, HC subclass, found in RING finger protein 141 (RNF141) and similar proteins; RNF141, also known as zinc finger protein 230 (ZNF230), is a RING finger protein present primarily in the nuclei of spermatogonia, the acrosome, and the tail of spermatozoa. It may have a broad function during early development of vertebrates. It plays an important role in spermatogenesis, including spermatogenic cell proliferation and sperm maturation, as well as motility and fertilization. It also exhibits DNA binding activity. RNF141/ZNF230 gene mutations may be associated with azoospermia. RNF141 contains a C3HC4-type RING finger domain that may function as an activator module in transcription.

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                  ....*....|....*....|....*....|....*....|
gi 1720413268   7 CIICQDLLHDCvsLQPCMHTFCAACYSGWMERSSLCPTCR 46
Cdd:cd16545     3 CCICMDRKADL--ILPCAHSYCQKCIDKWSDRHRTCPICR 40

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

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                  ....*....|....*....|....*....|....*....|....*.
gi 1720413268   7 CIICQDLLHDC--VSLQPCMHTFCAACYSGWMERSSLCPTCRCPVE 50
Cdd:cd16681    13 CTICLSILEEGedVRRLPCMHLFHQVCVDQWLITNKKCPICRVDIE 58

RING finger, H2 subclass, found in protein E3 ubiquitin-protein ligase Praja-1, Praja-2, and similar proteins; This family includes two highly similar E3 ubiquitin-protein ligases, Praja-1 and Praja-2. Praja-1, also known as RING finger protein 70, is a RING-H2 finger ubiquitin ligase encoded by gene PJA1, a novel human X chromosome gene abundantly expressed in the brain. It has been implicated in bone and liver development, as well as memory formation and X-linked mental retardation (MRX). Praja-1 interacts with and activates the ubiquitin-conjugating enzyme UbcH5B, and shows E2-dependent E3 ubiquitin ligase activity. It is a 3-deazaneplanocin A (DZNep)-induced ubiquitin ligase that directly ubiquitinates individual polycomb repressive complex 2 (PRC2) subunits in a cell free system, which leads to their proteasomal degradation. It also plays an important role in neuronal plasticity, which is the basis for learning and memory. Moreover, Praja-1 ubiquitinates embryonic liver fodrin (ELF) and Smad3, but not Smad4, in a transforming growth factor-beta (TGF-beta)-dependent manner. It controls ELF abundance through ubiquitin-mediated degradation, and further regulates TGF-beta signaling, which plays a key role in the suppression of gastric carcinoma. Praja-1 also regulates the transcription function of the homeodomain protein Dlx5 by controlling the stability of Dlxin-1, via a ubiquitin-dependent degradation pathway. Praja-2, also known as RING finger protein 131, NEURODAP1, or KIAA0438, is an E2-dependent E3 ubiquitin ligase that interacts with and activates the ubiquitin-conjugating enzyme UbcH5B. It functions as an A-kinase anchoring protein (AKAP)-like E3 ubiquitin ligase that plays a critical role in controlling cyclic AMP (cAMP)-dependent PKA activity and pro-survival signaling, and further promotes cell proliferation and growth. Praja-2 is also involved in protein sorting at the postsynaptic density region of axosomatic synapses and possibly plays a role in synaptic communication and plasticity. Together with the AMPK-related kinase SIK2 and the CDK5 activator CDK5R1/p35, it forms a SIK2-p35-PJA2 complex that plays an essential role for glucose homeostasis in pancreatic beta cell functional compensation. Praja-2 ubiquitylates and degrades Mob, a core component of NDR/LATS kinase and a positive regulator of the tumor-suppressor Hippo signaling. Both Praja-1 and Praja-2 contain a potential nuclear localization signal (NLS) and a C-terminal C3H2C3-type RING-H2 motif.

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                  ....*....|....*....|....*....|....*....|....
gi 1720413268   6 TCIICQD--LLHDCVSLQPCMHTFCAACYSGWMERSSLCPTCRC 47
Cdd:cd16465     1 CCPICCSeyVKDEIATELPCHHLFHKPCITAWLQKSGTCPVCRH 44

RING finger, HC subclass, found in tripartite motif-containing protein 72 (TRIM72) and similar proteins; TRIM72, also known as Mitsugumin-53 (MG53), is a muscle-specific protein that plays a central role in cell membrane repair by nucleating the assembly of the repair machinery at muscle injury sites. It is required in repair of alveolar epithelial cells under plasma membrane stress failure. It interacts with dysferlin to regulate sarcolemmal repair. Upregulation of TRIM72 develops obesity, systemic insulin resistance, dyslipidemia, and hyperglycemia, as well as induces diabetic cardiomyopathy through transcriptional activation of the peroxisome proliferation-activated receptor alpha (PPAR-alpha) signaling pathway. Compensation for the absence of AKT signaling by ERK signaling during TRIM72 overexpression leads to pathological hypertrophy. Moreover, TRIM72 functions as a novel negative feedback regulator of myogenesis by targeting insulin receptor substrate-1 (IRS-1). It is transcriptionally activated by the synergism of myogenin (MyoD) and myocyte enhancer factor 2 (MEF2). TRIM72 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 1720413268   1 MEETLTCIICQDLLHDCVSLQpCMHTFCAACYSGWME----RSSLCPTCRCP--VERICKN 55
Cdd:cd16612     1 MHQDLSCPLCLKLFQSPVTTE-CGHTFCQDCLSRVPKeedgGSTSCPTCQAPtkPEQLSIN 60

RING finger, H2 subclass, found in RING finger proteins RNF111, RNF165, and similar proteins; The family includes RING finger proteins RNF111, RNF165, and similar proteins. RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It also interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. The N-terminal half of RNF111 harbors three SUMO-interacting motifs (SIMs). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. Both RNF165 and RNF111 contain a C-terminal C3H2C3-type RING-H2 finger.

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                  ....*....|....*....|....*....|....*....|..
gi 1720413268   7 CIICQDLLH--DCVSLQPCMHTFCAACYSGWMERSSLCPTCR 46
Cdd:cd16474     3 CTICLSDFEegEDVRRLPCMHLFHQECVDQWLSTNKRCPICR 44

PBZ domain; This domain is a zinc-finger motif that in humans is part of the APLF, aprataxin- and PNK-like forkhead association domain-containing protein. The ZnF is highly conserved both in primary sequence and in the spacing between the putative zinc coordinating residues and is configured CX5CX6HX5H. Many of the proteins containing the APLF-like ZnF are involved in DNA strand break repair and/or contain domains implicated in DNA metabolism.

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                  ....*....|....*....|....
gi 1720413268 336 RPDCYWGRNCRTQvKAHHAMKFNH 359
Cdd:pfam10283   1 RPPCKYGAKCYRK-NPQHFKEFSH 23

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Cbl-c and similar proteins; Cbl-c, also known as RING finger protein 57 (RNF57), SH3-binding protein Cbl-3, SH3-binding protein Cbl-c, or signal transduction protein Cbl-c, is an E3 ubiquitin-protein ligase expressed exclusively in epithelial cells. It contains a tyrosine-kinase-binding domain (TKB, also known as the phosphotyrosine binding PTB domain, composed of a four helix-bundle, a Ca2+ binding EF-hand and a highly variant SH2 domain), a C3HC4-type RING-HC finger, and a short proline-rich region, but lacks the ubiquitin-associated (UBA) leucine zipper motif that are present in Cbl and Cbl-b. Cbl-c acts as a regulator of epidermal growth factor receptor (EGFR)-mediated signal transduction. It also suppresses v-Src-induced transformation through ubiquitin-dependent protein degradation. Moreover, Cbl-c ubiquitinates and downregulates RETMEN2A and implicates Enigma (PDLIM7) as a positive regulator of RETMEN2A by blocking Cbl-mediated ubiquitination and degradation. The ubiquitin ligase activity of Cbl-c is increased via the interaction of its RING-HC finger domain with a LIM domain of the paxillin homolog, hydrogen peroxide induced construct 5 (Hic-5).

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                  ....*....|....*....|....*....|....*....|....*
gi 1720413268   7 CIICQDLLHDcVSLQPCMHTFCAACYSGWMER-SSLCPTCRCPVE 50
Cdd:cd16710    16 CKICAERDKD-VRIEPCGHLLCSCCLAAWQHSdSQTCPFCRCEIK 59