Warner Claire L, Stewart Abigail, Luzio J Paul, Steel Karen P, Libby Richard T, Kendrick-Jones John, Buss Folma
MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.
EMBO J. 2003 Feb 3;22(3):569-79. doi: 10.1093/emboj/cdg055.
Golgi morphology and function are dependent on an intact microtubule and actin cytoskeleton. Myosin VI, an unusual actin-based motor protein moving towards the minus ends of actin filaments, has been localized to the Golgi complex at the light and electron microscopic level. Myosin VI is present in purified Golgi membranes as a peripheral membrane protein, targeted by its globular tail domain. To investigate the function of myosin VI at the Golgi complex, immortal fibroblastic cell lines of Snell's waltzer mice lacking myosin VI were established. In these cell lines, where myosin VI is absent, the Golgi complex is reduced in size by approximately 40% compared with wild-type cells. Furthermore, protein secretion of a reporter protein from Snell's waltzer cells is also reduced by 40% compared with wild-type cells. Rescue experiments showed that fully functional myosin VI was able to restore Golgi complex morphology and protein secretion in Snell's waltzer cells to the same level as that observed in wild-type cells.
高尔基体的形态和功能依赖于完整的微管和肌动蛋白细胞骨架。肌球蛋白VI是一种不同寻常的基于肌动蛋白的马达蛋白，朝着肌动蛋白丝的负端移动，在光学和电子显微镜水平上已被定位到高尔基体复合体。肌球蛋白VI作为一种外周膜蛋白存在于纯化的高尔基体膜中，由其球状尾部结构域靶向定位。为了研究肌球蛋白VI在高尔基体复合体中的功能，建立了缺乏肌球蛋白VI的斯内尔华尔兹小鼠的永生成纤维细胞系。在这些缺乏肌球蛋白VI的细胞系中，高尔基体复合体的大小与野生型细胞相比减少了约40%。此外，与野生型细胞相比，来自斯内尔华尔兹细胞的报告蛋白的蛋白质分泌也减少了4%。拯救实验表明，功能完全正常的肌球蛋白VI能够将斯内尔华尔兹细胞中的高尔基体复合体形态和蛋白质分泌恢复到与野生型细胞中观察到的相同水平。
