Gutjahr T, Frei E, Noll M
Institute of Molecular Biology II, University of Zürich, Switzerland.
Development. 1993 Feb;117(2):609-23. doi: 10.1242/dev.117.2.609.
The paired gene is one of approximately 30 zygotic segmentation genes responsible for establishing the segmented body plan of Drosophila melanogaster. To gain insight into the mechanism by which the paired gene is expressed in a complex temporal and spatial pattern, we have examined paired protein expression in wild-type and mutant embryos. In wild-type embryos, paired protein is expressed in several phases. Initial expression in broad domains evolves into a pair-rule pattern of eight stripes during cellularization. Subsequently, a segment-polarity-like pattern of fourteen stripes emerges. Later, at mid-embryogenesis, paired is expressed in specific regions of the head and in specific cells of the central nervous system. Analysis of the initial paired expression in the primary pair-rule mutants even-skipped, runt and hairy, and in all gap mutants suggests that the products of the gap genes hunchback, Krüppel, knirps and giant activate paired expression in stripes. With the exception of stripe 1, which is activated by even-skipped, and stripe 8, which depends upon runt, the primary pair-rule proteins are required for subsequent modulation rather than activation of the paired stripes. The factors activating paired expression in the pair-rule mode appear to interact with those activating it along the dorsoventral axis.
配对基因是大约30个合子体节基因之一，负责建立黑腹果蝇的体节模式。为了深入了解配对基因以复杂的时间和空间模式表达的机制，我们研究了野生型和突变型胚胎中配对蛋白的表达。在野生型胚胎中，配对蛋白在几个阶段表达。在细胞化过程中，广泛区域的初始表达演变成八条条纹的成对规则模式。随后，出现了十四条条纹的类似体节极性的模式。后来，在胚胎发育中期，配对基因在头部的特定区域和中枢神经系统的特定细胞中表达。对主要成对规则突变体偶数缺失、矮胖和多毛，以及所有间隙突变体中配对基因初始表达的分析表明，间隙基因驼背、克鲁佩尔、克尼普斯和巨人的产物激活了条纹中的配对基因表达。除了由偶数缺失激活的条纹1和依赖于矮胖的条纹8外，主要的成对规则蛋白是后续调节配对条纹所必需的，而不是激活配对条纹。以成对规则模式激活配对基因表达的因子似乎与沿背腹轴激活它的因子相互作用。
