Bennett Richard D, Caride Ariel J, Mauer Amy S, Strehler Emanuel E
Cell Biology and Genetics Program, Mayo Graduate School, Rochester, MN 55905, USA.
FEBS Lett. 2008 Jul 9;582(16):2377-81. doi: 10.1016/j.febslet.2008.05.051. Epub 2008 Jun 18.
Calmodulin-like protein (CLP) is a specific light chain of unconventional myosin-10 (Myo10) and enhances Myo10-dependent filopodial extension. Here we show that phenylalanine-795 in the third IQ domain (IQ3) of Myo10 is critical for CLP binding. Remarkably, mutation of F795 to alanine had little effect on calmodulin binding to IQ3. Fluorescence microscopy and time-lapse video microscopy showed that HeLa cells expressing CLP and transiently transfected with GFP-Myo10-F795A exhibited significantly shorter filopodia and decreased intrafilopodial motility compared to wildtype GFP-Myo10-transfected cells. Thus, F795 represents a unique anchor for CLP and is essential for CLP-mediated Myo10 function in filopodial extension and motility.
类钙调蛋白（CLP）是非常规肌球蛋白-10（Myo10）的特定轻链，并增强Myo10依赖的丝状伪足延伸。在此我们表明，Myo10第三个IQ结构域（IQ3）中的苯丙氨酸-795对于CLP结合至关重要。值得注意的是，F795突变为丙氨酸对钙调蛋白与IQ3的结合影响很小。荧光显微镜和延时视频显微镜显示，与野生型绿色荧光蛋白（GFP）-Myo10转染细胞相比，表达CLP并瞬时转染GFP-Myo10-F795A的HeLa细胞丝状伪足明显更短，丝状伪足内的运动性降低。因此，F795是CLP的独特锚定位点，对于CLP介导的Myo10在丝状伪足延伸和运动中的功能至关重要。
