Provance D William, Gourley Christopher R, Silan Colleen M, Cameron L C, Shokat Kevan M, Goldenring James R, Shah Kavita, Gillespie Peter G, Mercer John A
McLaughlin Research Institute, Great Falls, MT 59405, USA.
Proc Natl Acad Sci U S A. 2004 Feb 17;101(7):1868-73. doi: 10.1073/pnas.0305895101. Epub 2004 Feb 6.
Selective, in situ inhibition of individual unconventional myosins is a powerful approach to determine their specific physiological functions. Here, we report the engineering of a myosin Vb mutant that still hydrolyzes ATP, yet is selectively sensitized to an N(6)-substituted ADP analog that inhibits its activity, causing it to remain tightly bound to actin. Inhibition of the sensitized mutant causes inhibition of accumulation of transferrin in the cytoplasm and increases levels of plasma-membrane transferrin receptor, suggesting that myosin Vb functions in traffic between peripheral and pericentrosomal compartments.
对单个非常规肌球蛋白进行选择性原位抑制是确定其特定生理功能的有力方法。在此，我们报告了一种肌球蛋白Vb突变体的构建，该突变体仍能水解ATP，但对一种抑制其活性的N(6)-取代ADP类似物具有选择性敏感性，导致其与肌动蛋白紧密结合。对这种敏感突变体的抑制会导致细胞质中转铁蛋白积累的抑制，并增加质膜转铁蛋白受体的水平，这表明肌球蛋白Vb在周边和中心体周围区室之间的运输中发挥作用。
