F-actin

例句：

1. 1. Actin is a protein that helps cells move and contract.
   肌动蛋白是一种帮助细胞移动和收缩的蛋白质。
2. 2.The actin filaments are the basic units of muscle structure.
   肌动纤维是肌肉结构的基本单位。
3. 3. Actin plays a crucial role in cell division and movement.
   肌动蛋白在细胞分裂和运动中起着关键作用。