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Engineering Cell-permeable Protein
Published on: December 28, 2009
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信号是蛋白转位酶的全激活剂
Giorgos Gouridis1, Spyridoula Karamanou, Ioannis Gelis
1Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-Hellas, Iraklio, Crete 71110, Greece.
Nature
|November 20, 2009
概括
信号对于细菌蛋白质分泌是必不可少的,作为转位酶的全激活剂. 这种新发现的功能,除了准,驱动蛋白质转移通过不同的激活状态.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 外细胞质蛋白质被合成为前蛋白质,与信号一起通过转位酶分泌.
- 主要的细菌转位酶涉及SecYEG通道和Seca ATPase电机.
- SecA调解了大多数周等离子体和分泌蛋白的翻译后出口,SecB和信号参与了向.
研究的目的:
- 研究信号在细菌蛋白质分泌中的作用.
- 阐明信号与转位酶相互作用的机制.
- 为了确定信号是否具有超出预蛋白向的功能.
主要方法:
- 研究了SecA转位酶通过信号的全激活.
- 分析了转位酶激活的顺序状态:触发,捕获和分泌.
- 评估了成熟蛋白质域与信号在蛋白质向和分泌中的贡献.
主要成果:
- 信号是细菌转位酶的必不可少的全激活剂,而不仅仅是向因素.
- 信号与SecA结合会诱导三个连续的功能状态:触发,捕获和分泌.
- 成熟的蛋白质域对准有显著的贡献,使得信号对准比以前认为的不那么重要.
结论:
- 信号对于蛋白质分泌至关重要,因为它们作为转位酶的全激活剂.
- 涉及信号的全激活机制可能在不同的蛋白质转位中保持.
- 重新思考信号的主要功能,从单纯的向到基本的全激活是有必要的.
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