Italiano J E, Roberts T M, Stewart M, Fontana C A
Department of Biological Science, Florida State University, Tallahassee 32306, USA.
Cell. 1996 Jan 12;84(1):105-14. doi: 10.1016/s0092-8674(00)80997-6.
We have developed an in vitro motility system from Ascaris sperm, unique amoeboid cells that use filament arrays composed of major sperm protein (MSP) instead of an actin-based apparatus for locomotion. Addition of ATP to sperm extracts induces formation of fibers approximately 2 microns in diameter. These fibers display the key features of the MSP cytoskeleton in vivo. Each fiber consists of a meshwork of MSP filaments and has at one end a vesicle derived from the plasma membrane at the leading edge of the cell. Fiber growth is due to filament assembly at the vesicle; thus, fiber elongation results in vesicle translocation. This in vitro system demonstrates directly that localized polymerization and bundling of filaments can move membranes and provides a powerful assay for evaluating the molecular mechanism of amoeboid cell motility.
我们从蛔虫精子中开发了一种体外运动系统，蛔虫精子是独特的变形细胞，其利用由主要精子蛋白（MSP）组成的丝状阵列，而非基于肌动蛋白的装置进行运动。向精子提取物中添加ATP会诱导形成直径约2微米的纤维。这些纤维展现出体内MSP细胞骨架的关键特征。每根纤维由MSP细丝网络组成，并且在一端有一个源自细胞前缘质膜的囊泡。纤维生长归因于囊泡处的细丝组装；因此，纤维伸长导致囊泡移位。这个体外系统直接证明了细丝的局部聚合和成束能够移动膜，并为评估变形细胞运动的分子机制提供了一个强大的检测方法。
