Clark H F, Brentrup D, Schneitz K, Bieber A, Goodman C, Noll M
Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley 94720, USA.
Genes Dev. 1995 Jun 15;9(12):1530-42. doi: 10.1101/gad.9.12.1530.
Mutations in the dachsous gene of Drosophila lead to striking defects in the morphogenesis of the thorax, legs, and wings. The dachsous gene has been cloned and shown to encode a huge transmembrane protein that is a member of the cadherin superfamily, similar to the fat gene reported previously. Both the Dachsous and Fat proteins contain large tandem arrays of cadherin domains--27 and 34, respectively--as compared with 4 cadherin domains in classic vertebrate cadherins. In addition, Dachsous and Fat each has a cytoplasmic domain with sequence similarity to the cytoplasmic beta-catenin-binding domain of classic vertebrate cadherins. The dachsous gene is expressed in the ectoderm of embryos, whereas its expression in larvae is restricted to imaginal discs and specific regions of the brain. The phenotypes of, and genetic interactions between dachsous and fat are consistent with a model in which cell proliferation and morphogenesis of imaginal structures depends on the coupled equilibria between homo- and heterophilic interactions of the Dachsous and Fat cadherin proteins.
果蝇中dachsous基因的突变会导致胸部、腿部和翅膀形态发生显著缺陷。dachsous基因已被克隆，并显示编码一种巨大的跨膜蛋白，它是钙黏蛋白超家族的成员，与先前报道的fat基因相似。与经典脊椎动物钙黏蛋白中的4个钙黏蛋白结构域相比，Dachsous和Fat蛋白分别含有27个和34个钙黏蛋白结构域的大串联阵列。此外，Dachsous和Fat各自具有一个细胞质结构域，其序列与经典脊椎动物钙黏蛋白的细胞质β-连环蛋白结合结构域相似。dachsous基因在胚胎的外胚层中表达，而其在幼虫中的表达仅限于成虫盘和大脑的特定区域。dachsous和fat之间的表型及遗传相互作用与一种模型一致，即成虫结构的细胞增殖和形态发生取决于Dachsous和Fat钙黏蛋白同嗜性和异嗜性相互作用之间的耦合平衡。
