汉塞努拉多态型线粒体载体家族蛋白Mir1在过氧体和线粒体的双重局部化
Marc Pilegaard Pedersen1, Justina C Wolters2, Rinse de Boer1
1Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands.
概括
酵母中的线粒体酸盐载体Mir1具有对线粒体和过氧体的双重定位. 特定的过氧素 (Pex3,Pex19) 和全长的Mir1对于其过氧体向至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 机体生物学 机体生物学
- 贩卖蛋白质 贩卖蛋白质 是一个问题.
背景情况:
- 过氧体是具有不同代谢作用的重要器官.
- 有效的功能需要分子穿过氧体膜的运输.
- 氧体载体的鉴定仍然是一个活跃的研究领域.
研究的目的:
- 通过质谱学识别新的多氧体膜蛋白.
- 为了研究线粒体酸盐载体Mir1.1.的双重定位.
- 阐明控制Mir1对氧体进行分类的分子机制.
主要方法:
- 从Hansenula polymorpha中净化过氧体膜分量的蛋白质组学分析,使用非向的无标签量化质谱学.
- 基于光显微镜的蛋白质局部化研究在野生类型和突变酵母菌株.
- 对切断的Mir1变体进行分析,以确定功能排序域.
主要成果:
- 质谱测量确定了已知的过氧体蛋白和意想不到的线粒体载体,包括Mir1.1.
- Mir1对线粒体和过氧体都表现出双重定位.
- 佩克斯3和佩克斯19对于Mir1的氧体向是必不可少的,而只有一个特定的域 (跨膜域3-6),在截断的版本中显示了氧体定位.
- 对于过氧体局部化,需要全长的Mir1,这表明蛋白质内有多个线粒体排序信号.
结论:
- 线粒体酸盐载体Mir1是H. polymorpha.中的双局部蛋白质.
- Mir1的过氧体向取决于过氧素Pex3和Pex19.
- 全长的Mir1,而不仅仅是特定的域,对于过氧体排序是必要的,表明复杂的调节机制.
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