Thummel C S
Howard Hughes Medical Institute, Department of Human Genetics, University of Utah Medical Center, Salt Lake City 84132.
Bioessays. 1990 Dec;12(12):561-8. doi: 10.1002/bies.950121202.
Sixteen years ago, Michael Ashburner and his colleagues proposed a hierarchical model for the genetic control of polytene chromosome puffing by the steroid hormone ecdysone. The recent molecular isolation and characterization of three early ecdysone-inducible genes has confirmed many aspects of this model--these genes are directly induced by ecdysone, repressed by ecdysone-induced proteins, and appear to encode DNA binding regulatory proteins. The three early genes are also remarkably similar in structure. They are all unusually long and complex, with multiple transcripts that direct the synthesis of several related proteins from each locus. Proteins encoded by two of the early genes bind to both early and late ecdysone-induced puffs, implying that they are key regulators in the hierarchy.
16年前，迈克尔·阿什伯纳及其同事提出了一种层级模型，用于解释类固醇激素蜕皮激素对多线染色体胀泡的基因控制。近期对三个早期蜕皮激素诱导基因的分子分离和特性分析证实了该模型的诸多方面——这些基因直接由蜕皮激素诱导，被蜕皮激素诱导蛋白所抑制，并且似乎编码DNA结合调节蛋白。这三个早期基因在结构上也极为相似。它们都异常长且复杂，有多个转录本，这些转录本指导着每个基因座合成几种相关蛋白质。两个早期基因编码的蛋白质与早期和晚期蜕皮激素诱导的胀泡都能结合，这表明它们是该层级中的关键调节因子。
