Gabay L, Scholz H, Golembo M, Klaes A, Shilo B Z, Klämbt C
Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
Development. 1996 Nov;122(11):3355-62. doi: 10.1242/dev.122.11.3355.
The induction of different cell fates along the dorsoventral axis of the Drosophila embryo requires a graded activity of the EGF receptor tyrosine kinase (DER). Here we have identified primary and secondary target genes of DER, which mediate the determination of discrete ventral cell fates. High levels of DER activation in the ventralmost cells trigger expression of the transcription factors encoded by ventral nervous system defective (vnd) and pointed P1 (pntPl). Concomitant with the induction of pntP1, high levels of DER activity lead to inactivation of the Yan protein, a transcriptional repressor of Pointed-target genes. These two antagonizing transcription factors subsequently control the expression of secondary target genes such as otd, argos and tartan. The simultaneous effects of the DER pathway on pntP1 induction and Yan inactivation may contribute to the definition of the border of the ventralmost cell fates.
果蝇胚胎背腹轴上不同细胞命运的诱导需要表皮生长因子受体酪氨酸激酶（DER）的梯度活性。在这里，我们鉴定了DER的初级和次级靶基因，它们介导离散腹侧细胞命运的确定。最腹侧细胞中高水平的DER激活触发了由腹侧神经系统缺陷（vnd）和尖状P1（pntPl）编码的转录因子的表达。伴随着pntP1的诱导，高水平的DER活性导致Yan蛋白失活，Yan蛋白是尖状靶基因的转录抑制因子。这两种拮抗转录因子随后控制次级靶基因如otd、argos和格子花纹的表达。DER途径对pntP1诱导和Yan失活的同时作用可能有助于界定最腹侧细胞命运的边界。
