Myosin Vb involvement in plasma membrane recycling

极化的上皮细胞是细胞有组织运输重要性的一个戏剧性的例子 组件。这些细胞必须与两个不同的环境相互作用，一个在它们的顶端表面，另一个在它们的顶端 在它们的底面/侧面。戈登林实验室之前的工作已经表明，小分子的复合体 GTP酶Rab11a和非常规分子马达肌球蛋白VB在根尖运输中起重要作用 极化上皮细胞中的质膜回收小泡。具体和随机的结合 将利用突变分析和酵母双杂交筛选来确定 肌球蛋白VB与其结合伙伴Rab11a和Rab11-FIP2相互作用的结构基础。 此外，内源性肌球蛋白VB马达复合体的成分将从人类中分离出来 免疫沉淀法从H/K-ATPase富集型微管囊泡中分离胃壁细胞 该络合物成员的身份将通过质谱学来确定。这项工作的成果 将有助于发现肌球蛋白VB的调节机制，这反过来将促进我们的 了解极化细胞中膜循环的一般机制。

Polarized epithelial cells are a dramatic example of the importance of the organized transport of cellular components. These cells must interact with two distinct environments, one on their apical surface and one on their basal/lateral surfaces. Previous work in the Goldenring lab has shown that the complex of the small GTPase Rab11a and the unconventional molecular motor myosin Vb are important in the apical transport of plasma membrane recycling vesicles in polarized epithelial cells. A combination of specific and random mutational analysis complemented by yeast two-hybrid screening will be utilized in order to determine the structural basis of the interaction between myosin Vb and its binding partners Rab11a and Rab11-FIP2. Additionaly, the components of the endogenous myosin Vb motor complex will be isolated from human gastric parietal cells by immunoprecipitaion of the motor from H/K-ATPase-enriched tubulovesicles, and the identities of the members of the complex will be determined by mass spectroscopy. Results from this work will aid in discovering the mechanisms of regulation of myosin Vb, which in turn will advance our understanding of the general mechanisms of membrane recycling in polarized cells.