Alpha spectrin is essential for morphogenesis and body wall muscle formation in Caenorhabditis elegans.
Alpha spectrin is essential for morphogenesis and body wall muscle formation in Caenorhabditis elegans.
复制标题
alpha谱对于秀丽隐杆线虫的形态发生和身体壁肌的形成至关重要。
DOI：
10.1083/jcb.200111051
复制
发表时间：
2002-05-13
影响因子：
7.8
通讯作者：
Moerman, Donald G
中科院分区：
文献类型：
--
作者：
Norman, Kenneth R;Moerman, Donald G
多细胞动物的一个共同特征是细胞骨架谱的普遍存在。虽然在30多年前就发现了spectrin在非红细胞中的功能，但它的功能仍然是难以捉摸的。我们发现spc-1基因编码秀丽隐杆线虫基因组中唯一的α谱蛋白基因。在胚胎发生过程中，α谱蛋白在大多数细胞（如果不是所有细胞）的细胞膜上定位，开始于细胞的第一个阶段。有趣的是，这种定位依赖于β谱蛋白而不是β重谱蛋白。此外，对spc-1突变体的分析表明，β谱蛋白需要α谱蛋白才能稳定地募集到细胞膜上。缺乏功能性α谱蛋白的动物不能完成胚胎延伸，在孵化后即死亡。这些突变动物在皮下顶端肌动蛋白细胞骨架的组织中有缺陷，这是延长所必需的。此外，我们发现延伸的过程是体壁肌肉适当分化所必需的。具体而言，与野生型动物的肌丝相比，突变动物的体壁肌肌丝相对于胚胎的纵轴定向异常，体壁肌细胞没有发生正常的细胞形状变化。
Acommon feature of multicellular animals is the ubiquitous presence of the spectrin cytoskeleton. Although discovered over 30 yr ago, the function of spectrin in nonerythrocytes has remained elusive. We have found that the spc-1 gene encodes the only α spectrin gene in the Caenorhabditis elegans genome. During embryogenesis, α spectrin localizes to the cell membrane in most if not all cells, starting at the first cell stage. Interestingly, this localization is dependent on β spectrin but not βHeavy spectrin. Furthermore, analysis of spc-1 mutants indicates that β spectrin requires α spectrin to be stably recruited to the cell membrane. Animals lacking functional α spectrin fail to complete embryonic elongation and die just after hatching. These mutant animals have defects in the organization of the hypodermal apical actin cytoskeleton that is required for elongation. In addition, we find that the process of elongation is required for the proper differentiation of the body wall muscle. Specifically, when compared with myofilaments in wild-type animals the myofilaments of the body wall muscle in mutant animals are abnormally oriented relative to the longitudinal axis of the embryo, and the body wall muscle cells do not undergo normal cell shape changes.