Friederich E, Pringault E, Arpin M, Louvard D
Département de Biologie Moléculaire, Institut Pasteur, Paris.
Bioessays. 1990 Sep;12(9):403-8. doi: 10.1002/bies.950120902.
Villin, a calcium-regulated actin-binding protein, modulates the structure and assembly of actin filaments in vitro. It is organized into three domains, the first two of which are homologous. Villin is mainly produced in epithelial cells that develop a brush border and which are responsible for nutrient uptake. Expression of the villin structural gene is precisely regulated during mouse embryogenesis and is restricted in adults, to certain epithelia of the gastrointestinal and urogenital tracts. The function of villin has been assessed by transfecting CV1 cells with a human cDNA encoding wild-type villin or mutant villin. Synthesis of large amounts of villin in cells which do not normally produce this protein induces the growth of microvilli on the cell surface and the redistribution of F-actin, concomitant with the disappearance of stress fibers. The complete villin sequence is required for the morphogenic effect. These results suggest that villin plays a key role in the morphogenesis of microvilli.
绒毛蛋白是一种受钙调节的肌动蛋白结合蛋白，在体外可调节肌动蛋白丝的结构和组装。它由三个结构域组成，前两个结构域是同源的。绒毛蛋白主要在上皮细胞中产生，这些上皮细胞形成刷状缘并负责营养物质的吸收。在小鼠胚胎发育过程中，绒毛蛋白结构基因的表达受到精确调控，在成体中则局限于胃肠道和泌尿生殖道的某些上皮细胞。通过用编码野生型绒毛蛋白或突变型绒毛蛋白的人cDNA转染CV1细胞，对绒毛蛋白的功能进行了评估。在通常不产生这种蛋白的细胞中大量合成绒毛蛋白会诱导细胞表面微绒毛的生长以及F-肌动蛋白的重新分布，同时应力纤维消失。形态发生效应需要完整的绒毛蛋白序列。这些结果表明，绒毛蛋白在微绒毛的形态发生中起关键作用。
