Treisman J E, Lai Z C, Rubin G M
Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.
Development. 1995 Sep;121(9):2835-45. doi: 10.1242/dev.121.9.2835.
Differentiation in the Drosophila eye imaginal disc traverses the disc as a wave moving from posterior to anterior. The propagation of this wave is driven by hedgehog protein secreted by the differentiated cells in the posterior region of the disc. Hedgehog induces decapentaplegic expression at the front of differentiation, in the morphogenetic furrow. We have identified a gene, shortsighted, which is expressed in a hedgehog-dependent stripe in the undifferentiated cells just anterior to the furrow and which appears to be involved in the transmission of the differentiation-inducing signal; a reduction in shortsighted function leads to a delay in differentiation and to a loss of photoreceptors in the adult. shortsighted is also required for a morphogenetic movement in the brain that reorients the second optic lobe relative to the first. shortsighted encodes a cytoplasmic leucine zipper protein with homology to a mouse gene, TSC-22, which is transcriptionally induced in response to TGF-beta.
果蝇眼成虫盘的分化过程是作为一个从后向前移动的波穿过该成虫盘的。这个波的传播是由成虫盘后部已分化细胞分泌的刺猬蛋白驱动的。刺猬蛋白在分化前沿的形态发生沟中诱导果蝇的“五体不全”蛋白表达。我们鉴定出了一个基因，即“近视”基因，它在沟前方未分化细胞中呈刺猬蛋白依赖的条带形式表达，并且似乎参与了分化诱导信号传递；“近视”基因功能的降低会导致分化延迟以及成虫中光感受器缺失。“近视”基因对于大脑中使第二视叶相对于第一视叶重新定向的形态发生运动也是必需的。“近视”基因编码一种细胞质亮氨酸拉链蛋白，与小鼠基因TSC - 22具有同源性，TSC - 22在对转化生长因子β的应答中被转录诱导。
