细胞运动、细胞迁移与细胞骨架研究进展

细胞定向运动与细胞骨架的动态循环密切相关。运动细胞在其伪足前沿依靠细胞骨架的不断聚合推动细胞膜的前进，在基部靠近细胞体部位通过细胞骨架的不断解聚收缩拖拉细胞体向前运动，细胞骨架的聚合与解聚通过伪足与支撑表面的吸附与解吸附而偶连。肌动蛋白组成的微丝骨架是大多数运动细胞的主要成分。外界刺激引起微丝细胞骨架动态变化的信号通路已逐步明了。线虫精子细胞的运动行为与阿米巴变形运动相似，但是在线虫精子细胞中没有肌动蛋白，而是以精子主要蛋白为基础形成细胞骨架驱动精子细胞的运动。与肌动蛋白不同，精子主要蛋白没有分子极性、ATP结合位点和马达蛋白。通过比较研究以上两种运动体系将有助于在分子水平上进一步阐明细胞运动的机理。

RECENT PROGRESSES ON THE CELLULAR MOTILITY, CELL MIGRATION AND CYTOSKELETON

Cytoskeleton dynamics is essential for the directional cell motility and migration. Motile cells protrude the leading edge in their lamellipodia by the cytoskeletal assembly and pull the cell body forward by the disassembly and retraction of the cytoskeleton. The protrusion and retraction are coupled through cell attaching to and detaching from the substrate. Actin cytoskeleton is the major player in the cell motility and locomotion in most eukaryotic cells. The signal transduction pathways in the actin cytoskeletal treadmilling have been clarified recently. Acting like actin-based cell motility, the dynamics of nematode major sperm protein (MSP) cytoskeleton propels the worm sperm crawling. However, MSP cytoskeleton has no polarity, ATP binding site and motor protein, which are different from actin. As both systems display identical features of amoeboid locomotion, they may share very similar mechanical principles for cell migration.