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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 | 2007/11 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | Tom20 recognizes mitochondrial presequences through dynamic equilibrium among multiple bound states |
| 執筆形態 | その他 |
| 掲載誌名 | EMBO JOURNAL |
| 出版社・発行元 | NATURE PUBLISHING GROUP |
| 巻・号・頁 | 26(22),pp.4777-4787 |
| 著者・共著者 | Takashi Saitoh,Mayumi Igura,Takayuki Obita,Toyoyuki Ose,Rieko Kojima,Katsumi Maenaka,Toshiya Endo,Daisuke Kohda |
| 概要 | Most mitochondrial proteins are synthesized in the cytosol and imported into mitochondria. The N-terminal presequences of mitochondrial-precursor proteins contain a diverse consensus motif (phi chi chi phi phi, phi is hydrophobic and chi is any amino acid), which is recognized by the Tom20 protein on the mitochondrial surface. To reveal the structural basis of the broad selectivity of Tom20, the Tom20 presequence complex was crystallized. Tethering a presequence peptide to Tom20 through a disulfide bond was essential for crystallization. Unexpectedly, the two crystals with different linker designs provided unique relative orientations of the presequence with respect to Tom20, and neither configuration could fully account for the hydrophobic preference at the three hydrophobic positions of the consensus motif. We propose the existence of a dynamic equilibrium in solution among multiple states including the two bound states. In accordance, NMR N-15 relaxation analyses suggested motion on a sub-millisecond timescale at the Tom20-presequence interface. We suggest that the dynamic, multiple-mode interaction is the molecular mechanism facilitating the broadly selective specificity of the Tom20 receptor toward diverse mitochondrial presequences. |
| DOI | 10.1038/sj.emboj.7601888 |
| ISSN | 0261-4189 |