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エンドウ トシヤ
ENDO TOSHIYA
遠藤 斗志也 所属 京都産業大学 生命科学部 先端生命科学科 職種 客員教授 |
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| 言語種別 | 英語 |
| 発行・発表の年月 | 2009/01 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | Structural Stabilities of Different Regions of the Titin I27 Domain Contribute Differently to Unfolding upon Mitochondrial Protein Import |
| 執筆形態 | その他 |
| 掲載誌名 | JOURNAL OF MOLECULAR BIOLOGY |
| 出版社・発行元 | ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD |
| 巻・号・頁 | 385(3),pp.811-819 |
| 著者・共著者 | Takaomi Oguro,Keisuke Yagawa,Takaki Momose,Takehiro Sato,Koji Yamano,Toshiya Endo |
| 概要 | Protein import into mitochondria requires unfolding of the folded mature domain of precursor proteins. Here we compared the effects of amino-acid replacement between the core region and the N-terminal region of the titin 127 domain (the 27th Ig domain of human titin) on its import into isolated mitochondria when attached to a short presequence (pb(2)(35)). We found that several mutations in the core region around Trp34 of the 127 domain enhanced the import rates of the fusion proteins, while the N-terminal K6P mutation, which increases mechanical stability around the N-terminal region, decreases the import rate. When the K6P mutation is combined with core-destabilizing mutations, the import rates of the fusion proteins still decrease, unless a long segment is deleted. These results suggest that mutations in the core region could destabilize the transition state for unfolding from the intermediate with the detached N-terminal segment during import, leading to enhanced unfolding rates, although stabilization of the N-terminal region masks these effects. In other words, the rate-limiting step of the global unfolding upon import into mitochondria switches, depending on the balance between the stability of the N-terminal structure and the stability of the core region of the 127 domain. (C) 2008 Publislied by Elsevier Ltd. |
| DOI | 10.1016/j.jmb.2008.10.076 |
| ISSN | 0022-2836 |