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RNA-binding protein FUS/TLS (''F''used in ''S''arcoma/Translocated in Sarcoma) is a protein that in humans is encoded by the ''FUS'' gene.〔(【引用サイトリンク】 url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=2521 )〕 == Structure and function == The N-terminal end of FUS appears to be involved in transcriptional activation, while the C-terminal end is involved in protein and RNA binding. In addition recognition sites for the transcription factors AP2, GCF, Sp1 have been identified in FUS. FUS/TLS is a member of the TET protein family that also includes the EWS protein, the TATA-binding protein (TBP)-associated factor (TAFII68/TAF15) and the Drosophila cabeza/SARF protein. FUS/TLS, EWS and TAFII68/TAF15 have a similar structure characterised by an N-terminal QGSY-rich region, a highly conserved RNA recognition motif (RRM), multiple RGG repeats, which are extensively dimethylated at arginine residues and a C-terminal zinc finger motif.〔〔〔 FUS/TLS was initially identified as a fusion protein caused by chromosomal translocations in human cancers.〔〔 In these instances, the promoter and N-terminal part of FUS/TLS is translocated to the C-terminal domain of various DNA-binding transcription factors conferring a strong transcriptional activation domain to the fusion proteins.〔 FUS/TLS was independently identified as the hnRNP P2 protein, a subunit of a complex involved in maturation of pre-mRNA. Consistently, in vitro studies have shown that FUS/TLS binds RNA, single-stranded DNA and (with lower affinity) double-stranded DNA.〔〔 The sequence specificity of FUS/TLS binding to RNA or DNA has not been well established; however, using in vitro selection (SELEX), a common GGUG motif has been identified in approximately half of the RNA sequences bound by FUS/TLS. A later proposal was that the GGUG motif is recognised by the zinc finger domain and not the RRM (80). Additionally, FUS/TLS has been found to bind a relatively long region in the 3′ untranslated region (UTR) of the actin-stabilising protein Nd1-L mRNA, suggesting that rather than recognising specific short sequences, FUS/TLS interacts with multiple RNA-binding motifs or recognises secondary conformations. FUS/TLS has also been proposed to bind human telomeric RNA (UUAGGG)4 and single-stranded human telomeric DNA in vitro. Beyond nucleic acid binding, FUS/TLS was also found to associate with both general and more specialized protein factors to influence the initiation of transcription. Indeed, FUS/TLS interacts with several nuclear receptors. and with gene-specific transcription factors such as Spi-1/PU.1. or NF-κB. It also associates with the general transcriptional machinery and may influence transcription initiation and promoter selection by interacting with RNA polymerase II and the TFIID complex. Recently, FUS/TLS was also shown to repress the transcription of RNAP III genes and to co-immunoprecipitate with TBP and the TFIIIB complex. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「FUS」の詳細全文を読む スポンサード リンク
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