Function of Myosin VI

肌动蛋白为基础的分子运动肌球蛋白VI功能的内吞摄取途径，无论是在早期阶段的网格蛋白介导的摄取和后来的运输到/从早期内体。本研究使用荧光恢复后光漂白（FRAP）检查周转率肌球蛋白VI在胞吞作用。结果表明，肌球蛋白VI翻转动态的内吞结构与特征的半衰期共同的网格蛋白包被的结构上的大插入亚型的肌球蛋白VI和没有插入亚型的早期内体。该半衰期由肌球蛋白VI结合配偶体Dab 2共享，并且对于全长肌球蛋白VI和货物结合尾区是相同的。网格蛋白包被结构上的肌球蛋白VI的人工二聚化构建体的四倍慢的半衰期表明野生型肌球蛋白VI不作为稳定的二聚体起作用，而是作为单体或处于单体/二聚体平衡中。两者合计，这些FRAP结果提供了深入了解的基本营业额动态和单体/二聚体性质的肌球蛋白VI。

The actin-based molecular motor myosin VI functions in the endocytic uptake pathway, both during the early stages of clathrin-mediated uptake and in later transport to/from early endosomes. This study uses fluorescence recovery after photobleaching (FRAP) to examine the turnover rate of myosin VI during endocytosis. The results demonstrate that myosin VI turns over dynamically on endocytic structures with a characteristic half life common to both the large insert isoform of myosin VI on clathrin-coated structures and the no insert isoform on early endosomes. This half life is shared by the myosin VI binding partner Dab2 and is identical for fulllength myosin VI and the cargo-binding tail region. The four fold slower half life of an artificially dimerized construct of myosin VI on clathrin-coated structures suggests that wildtype myosin VI does not function as a stable dimer, but either as a monomer or in a monomer/dimer equilibrium. Taken together, these FRAP results offer insight into both the basic turnover dynamics and the monomer/dimer nature of myosin VI.