Chen J, Godt D, Gunsalus K, Kiss I, Goldberg M, Laski F A
Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA.
Nat Cell Biol. 2001 Feb;3(2):204-9. doi: 10.1038/35055120.
The driving force behind cell motility is the actin cytoskeleton. Filopodia and lamellipodia are formed by the polymerization and extension of actin filaments towards the cell membrane. This polymerization at the barbed end of the filament is balanced by depolymerization at the pointed end, recycling the actin in a 'treadmilling' process. One protein involved in this process is cofilin/actin-depolymerizing factor (ADF), which can depolymerize actin filaments, allowing treadmilling to occur at an accelerated rate. Cofilin/ADF is an actin-binding protein that is required for actin-filament disassembly, cytokinesis and the organization of muscle actin filaments. There is also evidence that cofilin/ADF enhances cell motility, although a direct requirement in vivo has not yet been shown. Here we show that Drosophila cofilin/ADF, which is encoded by the twinstar (tsr) gene, promotes cell movements during ovary development and oogenesis. During larval development, cofilin/ADF is required for the cell rearrangement needed for formation of terminal filaments, stacks of somatic cells that are important for the initiation of ovarioles. It is also required for the migration of border cells during oogenesis. These results show that cofilin/ADF is an important regulator of actin-based cell motility during Drosophila development.
细胞运动的驱动力是肌动蛋白细胞骨架。丝状伪足和片状伪足是由肌动蛋白丝向细胞膜聚合和延伸形成的。肌动蛋白丝尖端的聚合作用与另一端的解聚作用相平衡，在“踏车行为”过程中实现肌动蛋白的循环利用。参与这一过程的一种蛋白质是丝切蛋白/肌动蛋白解聚因子（ADF），它能使肌动蛋白丝解聚，从而使踏车行为加速发生。丝切蛋白/ADF是一种肌动蛋白结合蛋白，对于肌动蛋白丝的拆卸、胞质分裂以及肌肉肌动蛋白丝的组织是必需的。也有证据表明丝切蛋白/ADF能增强细胞运动性，尽管尚未证明其在体内是直接必需的。在此我们表明，由双星（tsr）基因编码的果蝇丝切蛋白/ADF在卵巢发育和卵子发生过程中促进细胞运动。在幼虫发育期间，丝切蛋白/ADF对于形成终丝所需的细胞重排是必需的，终丝是对卵巢管起始很重要的体细胞堆叠。它对于卵子发生过程中边缘细胞的迁移也是必需的。这些结果表明，丝切蛋白/ADF是果蝇发育过程中基于肌动蛋白的细胞运动的重要调节因子。
