Ross Mitchell W, Mitchell David J, Cain John C, Blasier Kiev R, Pfister K Kevin
Department of Cell Biology, University of Virginia, Charlottesville, VA, USA.
Methods Cell Biol. 2016;131:253-67. doi: 10.1016/bs.mcb.2015.06.020. Epub 2015 Sep 2.
Live cell imaging of the movement of various membrane-bounded organelle cargos has enhanced our understanding of their function. Eukaryotic cells utilize microtubules and two classes of microtubule-based motor proteins, cytoplasmic dynein and members of the kinesin family, to deliver a variety of membrane-bounded organelles and other cargos to their appropriate locations. In order to better understand the functions and regulation of cytoplasmic dynein, we developed a method to study its location and motility in living cells. The technique takes advantage of the long thin axons of cultured hippocampal neurons. We use calcium phosphate to transfect fluorescent-tagged dynein intermediate chain (IC) subunits (DYNC1I) into cultured neurons. When the ICs are expressed at low levels, they are effective probes for the location of the cytoplasmic dynein complex in axons when living cells are imaged with fluorescence microscopy. The fluorescent subunit probes can be used to identify specific cargos of dynein complexes with different IC isoforms as well as the kinetic properties of cytoplasmic dynein.
对各种膜结合细胞器货物运动的活细胞成像增进了我们对其功能的理解。真核细胞利用微管以及两类基于微管的运动蛋白,即胞质动力蛋白和驱动蛋白家族成员,将各种膜结合细胞器和其他货物运输到其适当位置。为了更好地理解胞质动力蛋白的功能和调控,我们开发了一种研究其在活细胞中的定位和运动性的方法。该技术利用了培养的海马神经元的细长轴突。我们使用磷酸钙将荧光标记的动力蛋白中间链(IC)亚基(DYNC1I)转染到培养的神经元中。当ICs以低水平表达时,在用荧光显微镜对活细胞进行成像时,它们是轴突中胞质动力蛋白复合体定位的有效探针。荧光亚基探针可用于识别具有不同IC同工型的动力蛋白复合体的特定货物以及胞质动力蛋白的动力学特性。