Gunning Peter W, Schevzov Galina, Kee Anthony J, Hardeman Edna C
Oncology Research Unit, The Children's Hospital at Westmead, Locked Bag 4001, Westmead NSW 2145, Australia.
Trends Cell Biol. 2005 Jun;15(6):333-41. doi: 10.1016/j.tcb.2005.04.007.
Actin filament functional diversity is paralleled by variation in the composition of isoforms of tropomyosin in these filaments. Although the role of tropomyosin is well understood in skeletal muscle, where it regulates the actin-myosin interaction, its role in the cytoskeleton has been obscure. The intracellular sorting of tropomyosin isoforms indicated a role in spatial specialization of actin filament function. Genetic manipulation and protein chemistry studies have confirmed that these isoforms are functionally distinct. Tropomyosins differ in their recruitment of myosin motors and their interaction with actin filament regulators such as ADF-cofilin. Tropomyosin isoforms have therefore provided a powerful mechanism to diversify actin filament function in different intracellular compartments.
肌动蛋白丝的功能多样性与这些丝中肌钙蛋白异构体组成的变化相对应。尽管肌钙蛋白在骨骼肌中调节肌动蛋白-肌球蛋白相互作用的作用已得到充分理解，但其在细胞骨架中的作用一直不清楚。肌钙蛋白异构体的细胞内分选表明其在肌动蛋白丝功能的空间特化中起作用。基因操作和蛋白质化学研究证实这些异构体在功能上是不同的。肌钙蛋白在募集肌球蛋白马达以及与肌动蛋白丝调节因子（如ADF-丝切蛋白）的相互作用方面存在差异。因此，肌钙蛋白异构体为不同细胞内区室中肌动蛋白丝功能的多样化提供了一种强大的机制。
