Wu Xufeng, Sakamoto Take, Zhang Fang, Sellers James R, Hammer John A
Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50 Room 2523 NIH 9000 Rockvill, Bethesda, MD 20892-8017, USA.
FEBS Lett. 2006 Oct 30;580(25):5863-8. doi: 10.1016/j.febslet.2006.09.047. Epub 2006 Oct 2.
Rab27a and melanophilin (Mlph) are required in vivo to form a melanosome receptor for myosin Va in which Rab27a anchored in the melanosome membrane recruits Mlph, which in turn recruits myosin Va. Here, we show by reconstitution using purified proteins that Rab27a and Mlph are sufficient to form a transport complex with myosin Va in vitro. These results suggest that additional proteins are not required in vivo for assembly of the myosin Va receptor, although other proteins may associate with this tripartite complex to regulate its activity and/or to assist Rab27a in anchoring the complex to the melanosome membrane.
Rab27a和黑色素亲和蛋白（Mlph）在体内是形成肌球蛋白Va的黑素小体受体所必需的，其中锚定在黑素小体膜上的Rab27a招募Mlph，而Mlph进而招募肌球蛋白Va。在此，我们通过使用纯化蛋白进行重组实验表明，Rab27a和Mlph在体外足以与肌球蛋白Va形成运输复合物。这些结果表明，体内组装肌球蛋白Va受体不需要其他蛋白质，尽管其他蛋白质可能与这个三方复合物结合以调节其活性和/或协助Rab27a将复合物锚定到黑素小体膜上。
