Nakagoshi H, Hoshi M, Nabeshima Y, Matsuzaki F
Department of Molecular Genetics, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan.
Genes Dev. 1998 Sep 1;12(17):2724-34. doi: 10.1101/gad.12.17.2724.
Morphogen gradients of secreted molecules play critical roles in the establishment of the spatial pattern of gene expression. During midgut development in Drosophila, secreted molecules of Decapentaplegic (Dpp) and Wingless (Wg) establish unique transcriptional regulation within target cells to specify the resultant cell types. Here we report the identification of a novel homeobox gene, defective proventriculus (dve), which is required for the midgut specification under the control of Dpp and Wg. In dve mutants, two distinct parts of the midgut, the proventriculus and middle midgut, are abnormally organized. The Wg signal regulates dve expression during proventriculus development. On the other hand, dve is a downstream target of Dpp in the middle midgut and defines the functional specificity of copper cells along with another Dpp target gene, labial. Thus, the dve gene acts under the two distinct extracellular signals at distant parts of the midgut primordia.
分泌分子的形态发生素梯度在基因表达空间模式的建立中起着关键作用。在果蝇中肠发育过程中，Decapentaplegic（Dpp）和Wingless（Wg）的分泌分子在靶细胞内建立独特的转录调控，以确定最终的细胞类型。在此，我们报告了一个新的同源框基因——缺陷前胃（dve）的鉴定，它是在Dpp和Wg控制下中肠特化所必需的。在dve突变体中，中肠的两个不同部分，即前胃和中肠中部，组织异常。Wg信号在胃前发育过程中调节dve的表达。另一方面，dve是中肠中部Dpp的下游靶标，并与另一个Dpp靶标基因labial一起定义了铜细胞的功能特异性。因此，dve基因在中肠原基的不同部位在两种不同的细胞外信号作用下起作用。
