Tautz D
Max-Planck Institut für Entwicklungsbiologie, Arbeitsgruppe Jäckle, Tübingen, FRG.
Nature. 1988 Mar 17;332(6161):281-4. doi: 10.1038/332281a0.
Segmentation in the inset embryo is initiated by maternally provided information, which is stored in the developing oocyte. In Drosophila, the genes necessary for this process have been genetically characterized. The anterior segmented region is organized by the bicoid (bcd) gene product. The posterior segmented region is organized by several interacting gene products, among them the oskar (osk) gene product. The first zygotic group of genes, which are thought to respond to the spatial cues provided by the maternal genes, are the gap genes, whose members include hunchback (hb), Krüppel (Kr) and knirps (kni). To elucidate the role played by the maternal genes in expression of the gap gene hb, antibodies were raised against a fusion protein and were used for the cytological localization of the hb gene product in wild-type and mutant embryos. The hb protein is predominantly located in the nucleus. Its spatial expression includes the formation of an anterior-posterior gradient during the early cleavage stages and a strong zygotic expression in the anterior half of the embryo. Analysis of embryos mutant for the maternal genes affecting the anterior-posterior segmentation pattern shows that the formation of the early gradient is controlled by the osk group of genes, whereas efficient activation of the zygotic anterior expression domain is dependent on bcd activity.
胚胎切片中的分割是由母体提供的信息启动的，这些信息存储在发育中的卵母细胞中。在果蝇中，这一过程所需的基因已通过遗传学方法进行了表征。前部的分割区域由双胸（bcd）基因产物组织。后部的分割区域由几种相互作用的基因产物组织，其中包括 Oskar（osk）基因产物。第一组合子基因被认为是对母体基因提供的空间线索做出反应，它们是裂隙基因，其成员包括驼背（hb）、克虏伯（Kr）和 knirps（kni）。为了阐明母体基因在裂隙基因 hb 表达中所起的作用，制备了针对融合蛋白的抗体，并将其用于在野生型和突变胚胎中对 hb 基因产物进行细胞学定位。hb 蛋白主要位于细胞核中。其空间表达包括在早期卵裂阶段形成前后梯度，以及在胚胎前半部分有强烈的合子表达。对影响前后分割模式的母体基因发生突变的胚胎进行分析表明，早期梯度的形成受 osk 基因群控制，而合子前表达域的有效激活则依赖于 bcd 活性。
