翻訳と辞書 Words near each other ・ Polysphaeria macrantha ・ Polysphalia ・ Polyptychus paupercula ・ Polyptychus potiendus ・ Polyptychus rougeoti ・ Polyptychus sinus ・ Polyptychus thihongae ・ Polyptychus trilineatus ・ Polyptychus trisecta ・ Polyptychus wojtusiaki ・ Polypure ・ Polypurine reverse-Hoogsteen hairpin ・ Polypyrenula ・ Polypyridine complex ・ Polypyridinium salts ・ Polypyrimidine tract ・ Polypyrimidine tract-binding protein ・ Polypyrrole ・ PolyQ (database) ・ Polyquaternium ・ Polyquinane ・ Polyradiculoneuropathy ・ Polyresin ・ Polyrhachis ・ Polyrhachis aedipus ・ Polyrhachis bugnioni ・ Polyrhachis convexa ・ Polyrhachis curvispina ・ Polyrhachis exercita ・ Polyrhachis gibbosa Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Polypyrimidine tract ： ウィキペディア英語版 Polypyrimidine tract The polypyrimidine tract is a region of messenger RNA (mRNA) that promotes the assembly of the spliceosome, the protein complex specialized for carrying out RNA splicing during the process of post-transcriptional modification. The region is rich with pyrimidine nucleotides, especially uracil, and is usually 15-20 base pairs long, located about 5-40 base pairs before the 3' end of the intron to be spliced.〔Lodish H, Berk A, Matsudaira P, Kaiser CA, Krieger M, Scott MP, Zipursky SL, Darnell J. (2004). ''Molecular Cell Biology.'' WH Freeman: New York, NY. 5th ed.〕 A number of protein factors bind to or associate with the polypyrimidine tract, including the spliceosome component U2AF and the ''polypyrimidine tract-binding protein'' (PTB), which plays a regulatory role in alternative splicing. PTB's primary function is in exon silencing, by which a particular exon region normally spliced into the mature mRNA is instead left out, resulting in the expression of an isoform of the protein for which the mRNA codes. Because PTB is ubiquitously expressed in many higher eukaryotes, it is thought to suppress the inclusion of "weak" exons with poorly defined splice sites.〔Wagner EJ, Garcia-Blanco MA. (2001). Polypyrimidine tract binding protein antagonizes exon definition. ''Mol Cell Biol'' 21(10):3281-3288.〕 However, PTB binding is not sufficient to suppress "robust" exons.〔Gooding C, Roberts GC, Smith CW. (1998). Role of an inhibitory pyrimidine element and polypyrimidine tract binding protein in repression of a regulated alpha-tropomyosin exon. ''RNA'' 4:85-100.〕 The suppression or selection of exons is critical to the proper expression of tissue-specific isoforms. For example, smooth muscle and skeletal muscle express alternate isoforms distinguished by mutually exclusive exon selection in alpha-tropomyosin.〔Gooding C, Roberts GC, Moreau G, Nadal-Ginard B, Smith CW. (1994). Smooth muscle-specific switching of alpha-tropomyosin mutually exclusive exon selection by specific inhibition of the strong default exon. ''EMBO J'' 13(16):3861-72.〕 ==References== 〔 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「Polypyrimidine tract」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.