-密里斯托伊尔开关的分子力学
1Department of Neurobiology, Stanford University School of Medicine, California 94305, USA.
Nature
|September 20, 1997
概括
结合会导致复原蛋白上的myristoyl组翻转出来,使其与细胞膜相互作用. 这种-密里斯托尔开关机制是古老的,并且在各种物种中得到保护.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 细胞生物学 细胞生物学
背景情况:
- 许多真核生物和病毒蛋白质在它们的氨基末端具有myristoyl组的修饰.
- 视网膜杆细胞中的传感器recoverin通过抑制罗多素激酶来调节光刺激的罗多素.
- 康沃林含有氨基末端的米里斯托尔基和四个EF手,分子质量为23K.
研究的目的:
- 为了研究在结合后恢复的结构变化.
- 阐明myristoyl组挤出和膜相互作用的机制.
- 为了理解-米里斯托伊尔开关的进化保存.
主要方法:
- 核磁共振 (NMR) 光谱被用来研究复原的结构和动态.
- 分析蛋白质结构的变化,以应对离子 (Ca2+) 结合.
主要成果:
- 结合诱导了myristoyl组从疏水口袋的解和挤出.
- 该myristoyl组成为可访问的与脂质双层膜的相互作用.
- 在氨基末端和碳氧末端域之间发生45度旋转,暴露了疏水性残留物.
结论:
- -米里斯托尔开关是控制敏感细胞过程的古老机制.
- 这种结构转变使得recoverin能够转移到磁盘膜.
- 在recoverin同类物种中保存的结构特征表明了基本的生物学作用.
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