U-box domain, a modified RING finger, found in Arabidopsis plant U-box proteins (AtPUB) and similar proteins; The plant PUB proteins, also known as U-box domain-containing proteins, are much more numerous in Arabidopsis which has 62 in comparison with the typical 6 in most animals. The majority of AtPUBs in this subfamily are known as ARM domain-containing PUB proteins, containing a C-terminally-located, tandem ARM (armadillo) repeat protein-interaction region in addition to the U-box domain. They have been implicated in the regulation of cell death and defense. They also play important roles in other plant-specific pathways, such as controlling both self-incompatibility and pseudo-self-incompatibility, as well as acting in abiotic stress. A subgroup of ARM domain-containing PUB proteins harbors a plant-specific U-box N-terminal domain.

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gi 1002309685  45 SAFLCPITMEVMRDPVVVETGHAFEREAIARWFSECASlgaapRCPVTMEV 95
Cdd:cd16664     2 EEFICPISLELMKDPVILATGQTYERAAIEKWLDSGNN-----TCPITGQP 47

U-box domain, a modified RING finger, found in Arabidopsis plant U-box proteins (AtPUB) and similar proteins; The plant PUB proteins, also known as U-box domain-containing proteins, are much more numerous in Arabidopsis which has 62 in comparison with the typical 6 in most animals. The majority of AtPUBs in this subfamily are known as ARM domain-containing PUB proteins, containing a C-terminally-located, tandem ARM (armadillo) repeat protein-interaction region in addition to the U-box domain. They have been implicated in the regulation of cell death and defense. They also play important roles in other plant-specific pathways, such as controlling both self-incompatibility and pseudo-self-incompatibility, as well as acting in abiotic stress. A subgroup of ARM domain-containing PUB proteins harbors a plant-specific U-box N-terminal domain.

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                  ....*....|....*....|....*....|....*....|....*....|.
gi 1002309685  45 SAFLCPITMEVMRDPVVVETGHAFEREAIARWFSECASlgaapRCPVTMEV 95
Cdd:cd16664     2 EEFICPISLELMKDPVILATGQTYERAAIEKWLDSGNN-----TCPITGQP 47

U-box domain; The U-box is a domain of ~70 amino acids that is present in proteins from yeast to human. It consists of the beta-beta-alpha-beta-alpha- fold typical of U-box and RING domains. The central alpha helix is flanked by two prominent surface-exposed loop regions. This domain is one class of E3 ligases, involved in the ubiquitination process. This domain is related to the Ring finger pfam00097 but lacks the zinc binding residues.

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gi 1002309685  47 FLCPITMEVMRDPVVVETGHAFEREAIARWFsecasLGAAPRCPVTMEVVDGADVKPVVALRAAIEEW 114
Cdd:pfam04564   5 FLDPITFELMTDPVILPSGITYDRSTIERHL-----LSVDPTDPFTREPLTHDQLIPNLELKAKIDAW 67

second U-box domain, a modified RING finger, found in Legionella pneumophila U-box protein LubX and similar proteins; LubX, also called RING-type E3 ubiquitin transferase LubX, is part of the large arsenal of effectors in Legionella pneumophila that are translocated into the host cytosol during infection. LubX acts as an E3 ubiquitin-protein ligase (EC 2.3.2.27) that interferes with the host's ubiquitination pathway. LubX contains two RING-like U-box domains. U-box 1 is critical to the ubiquitin ligase activity, and U-box 2 mediates interaction with host target. This model corresponds to the second one.

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gi 1002309685  45 SAFLCPITMEVMRDPVVVETGHAFEREAIARWFSECASlgaaprCPVTMEVVDGADVKPVVALRAAIEEWTSRR 118
Cdd:cd23150     2 DIFLCPISKTLIKTPVITAQGKVYDQEALSNFLIATGN------KDETGKKLSIDDVVVFDELYQQIKVYNFYR 69

first U-box domain, a modified RING finger, found in Legionella pneumophila U-box protein LubX and similar proteins; LubX, also called RING-type E3 ubiquitin transferase LubX, is part of the large arsenal of effectors in Legionella pneumophila that are translocated into the host cytosol during infection. LubX acts as an E3 ubiquitin-protein ligase (EC 2.3.2.27) that interferes with the host's ubiquitination pathway. LubX contains two RING-like U-box domains. U-box 1 is critical to the ubiquitin ligase activity, and U-box 2 mediates interaction with host target. This model corresponds to the first one.

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gi 1002309685  47 FLCPITMEVMRDPVVVETGHAFEREAIARWfsecasLGAAPRCPVTMEVVDGADVKP 103
Cdd:cd23149     1 FTCPITSGFMEDPVITPSGFSYERSAIERW------LETKPEDPQTREPLTAKDLQP 51

SP-RING finger and SPL-RING finger, variants of RING fingers; This family corresponds to a group of proteins with variants of RING fingers that are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues compared with the classic C3H2C3-/C3HC4-type RING fingers. They include SP-RING finger found in the Siz/PIAS RING (SP-RING) family of SUMO E3 ligases and SPL-RING finger found in E3 SUMO-protein ligase NSE2. The SP-RING family includes PIAS (protein inhibitor of activated STAT) proteins, Zmiz proteins, and Siz proteins from plants and fungi. The PIAS (protein inhibitor of activated STAT) protein family modulates the activity of several transcription factors and acts as an E3 ubiquitin ligase in the sumoylation pathway. NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress.

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gi 1002309685  47 FLCPITMEVMRDPVVVET-GHAFEREAIARWFSECaslGAAPRCPV 91
Cdd:cd16452     1 LKCPITQKRMKDPVRGKHcGHCFDLEAILQYLKRR---KKKWKCPV 43

U-box domain, a modified RING finger, found in ubiquitin conjugation factor E4 B (UBE4B) and similar proteins; UBE4B, also known as UFD2a, is a U-box-type ubiquitin-protein ligase that functions as an E3 ubiquitin ligase and an E4 polyubiquitin chain elongation factor, which catalyzes formation of Lys27- and Lys33-linked polyubiquitin chains rather than the Lys48-linked chain. It is a mammalian homolog of yeast UFD2 ubiquitination factor and it participates in the proteasomal degradation of misfolded or damaged proteins through association with chaperones. It is located in common neuroblastoma deletion regions and may be subject to mutations in tumors. UBE4B has contradictory functions upon tumorigenesis as an oncogene or tumor suppressor in different types of cancers. It is essential for Hdm2 (also known as Mdm2)-mediated p53 degradation. It mediates p53 polyubiquitination and degradation, as well as inhibits p53-dependent transactivation and apoptosis, and thus plays an important role in regulating phosphorylated p53 following DNA damage. UBE4B is also associated with other pathways independent of the p53 family, such as polyglutamine aggregation and Wallerian degeneration, both of which are critical in neurodegenerative diseases. Moreover, UBE4B acts as a regulator of epidermal growth factor receptor (EGFR) degradation. It is recruited to endosomes in response to EGFR activation by binding to Hrs, a key component of endosomal sorting complex required for transport (ESCRT) 0, and then regulates endosomal sorting, affecting cellular levels of the EGFR and its downstream signaling. UBE4B contains a ubiquitin elongating factor core and a RING-like U-box domain at the C-terminus.

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gi 1002309685  47 FLCPITMEVMRDPVVVETGHAFEREAIAR-WFSECASlgaaP--RCPVTMEvvdgaDVKPVVALRAAIEEWTSRRE 119
Cdd:cd16658     8 FLDPLMDTLMTDPVILPSGTIMDRSIILRhLLNSQTD----PfnRQPLTED-----MLEPVPELKERIQAWIREKQ 74

U-box domain, a modified RING finger, found in RING finger protein 37 (RNF37); RNF37, also known as KIAA0860, U-box domain-containing protein 5 (UBOX5), UbcM4-interacting protein 5 (UIP5), or ubiquitin-conjugating enzyme 7-interacting protein 5, is an E3 ubiquitin-protein ligase found exclusively in the nucleus as part of a nuclear dot-like structure. It interacts with the molecular chaperone VCP/p97 protein. RNF37 contains a U-box domain followed by a potential nuclear location signal (NLS), and a C-terminal C3HC4-type RING-HC finger. The U-box domain is a modified RING finger domain that lacks the hallmark metal-chelating cysteines and histidines of the latter, but is likely to adopt a RING finger-like conformation. The presence of the U-box, but not of the RING finger, is required for the E3 activity. The U-box domain can directly interact with several E2 enzymes, including UbcM2, UbcM3, UbcM4, UbcH5, and UbcH8, suggesting a similar function as the RING finger in the ubiquitination pathway. This model corresponds to the U-box domain.

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gi 1002309685  47 FLCPITMEVMRDPVVVETGHAFEREAIARWFSECASLGAAPRCPVTM 93
Cdd:cd16660     4 FLDPITCELMTLPVLLPSGKVVDQSTLEKYIKEEATWGRLPSDPFTG 50

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.

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gi 1002309685  49 CPITMEVMRDPVVVETGHAFEREAIARWFSECASLGAAPRC 89
Cdd:cd16594     8 CPICLDYFTDPVTLDCGHSFCRACIARCWEEPETSASCPQC 48

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

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gi 1002309685  47 FLCPITMEVMRDPVVVETGHAFEREAIARWF 77
Cdd:cd16497     2 FLCHCCYDLLVNPTTLNCGHSFCRHCLALWW 32

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).

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gi 1002309685  46 AFLCPITMEVMRDPVVVET-GHAFEREAIArwfsECASLgAAPRCPV 91
Cdd:cd16549     1 QFSCPICLEVYHKPVVITScGHTFCGECLQ----PCLQV-ASPLCPL 42

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 7 (TRAF7) and similar proteins; TRAF7, also known as RING finger and WD repeat-containing protein 1 or RING finger protein 119 (RNF119), is an E3 ubiquitin-protein ligase involved in signal transduction pathways that lead either to activation or repression of NF-kappaB transcription factor by promoting K29-linked ubiquitination of several cellular targets, including the NF-kappaB essential modulator (NEMO) and the p65 subunit of NF-kappaB transcription factor. It is also involved in K29-linked polyubiquitination that has been implicated in lysosomal degradation of proteins. Moreover, TRAF7 is required for K48-linked ubiquitination of p53, a key tumor suppressor and a master regulator of various signaling pathways, such as those related to apoptosis, cell cycle and DNA repair. It is also required for tumor necrosis factor alpha (TNFalpha)-induced Jun N-terminal kinase activation and promotes cell death by regulating polyubiquitination and lysosomal degradation of c-FLIP protein. Furthermore, TRAF7 functions as small ubiquitin-like modifier (SUMO) E3 ligase involved in other post-translational modification, such as sumoylation. It binds to and stimulates sumoylation of the proto-oncogene product c-Myb, a transcription factor regulating proliferation and differentiation of hematopoietic cells. It potentiates MEKK3-induced AP1 and CHOP activation and induces apoptosis. Meanwhile, TRAF7 mediates MyoD1 regulation of the pathway and cell-cycle progression in myoblasts. It also plays a role in Toll-like receptors (TLR) signaling. TRAF7 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and an adjacent zinc finger, and a unique C-terminal domain that comprises a coiled coil domain and seven WD40 repeats.

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gi 1002309685  49 CPITMEVMRDPVVVETGHAFEReaiarwfsECASLGAAPRCPV 91
Cdd:cd16644     8 CPLCQRVFKDPVITSCGHTFCR--------RCALTAPGEKCPV 42

RING finger, HC subclass, found in tripartite motif-containing protein 31 (TRIM31) and similar proteins; TRIM31 is an E3 ubiquitin-protein ligase that primarily localizes to the cytoplasm, but is also associated with the mitochondria. It can negatively regulate cell proliferation and may be a potential biomarker of gastric cancer as it is overexpressed from the early stage of gastric carcinogenesis. TRIM31 is downregulated in non-small cell lung cancer and serves as a potential tumor suppressor. It interacts with p52 (Shc) and inhibits Src-induced anchorage-independent growth. TRIM31 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, as well as an uncharacterized region positioned C-terminal to the RBCC domain.

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gi 1002309685  49 CPITMEVMRDPVVVETGHAFEREAIARWFSECASLGAAPRC 89
Cdd:cd16582     4 CPICLDILQKPVTIDCGHNFCLQCITQIGETSCGFFKCPLC 44

U-box domain, a modified RING finger, found in pre-mRNA-processing factor 19 (Prp19) and similar proteins; Prp19, also known as nuclear matrix protein 200 (NMP200), senescence evasion factor (SNEV), or DNA repair protein Pso4 (psoralen-sensitive mutant 4), is a ubiquitously expressed multifunctional E3 ubiquitin ligase with pleiotropic activities in DNA damage signaling, repair, and replicative senescence. It functions as a critical component of DNA repair and DNA damage checkpoint complexes. It senses DNA damage, binds double-stranded DNA in a sequence-independent manner, facilitates processing of damaged DNA, promotes DNA end joining, regulates replication protein A (RPA2) phosphorylation and ubiquitination at damaged DNA, and regulates RNA splicing and mitotic spindle formation in its integral capacity as a scaffold for a multimeric core complex. Prp19 contains an N-terminal E3 ubiquitin ligase U-box domain with E2 recruitment function that facilitates dimerization and is essential for its auto-ubiquitination activity in vitro or when overexpressed, a coiled-coil Prp19 homology region that mediates its tetramerization and interaction with CDC5L and SPF27, and a C-terminal seven-bladed WD40 beta-propeller type of leucine-rich architectural repeats that form an asymmetrical barrel-shaped structure important for substrate recognition and recruitment.

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gi 1002309685  47 FLCPITMEVMRDPVV-VETGHAFEREAIARWFSEcaslgaAPRCPVTMEVVDGADVKPV 104
Cdd:cd16656     1 MVCAISGEVPEEPVVsPKSGHVFEKRLIEKYIAE------NGTDPVTGEPLTEEDLIEI 53