Ouellette Rodney J, Valet Jean-Paul, Côté Serge
Unite d'Ontogénèse et de Génétique Moléculaire, Centre de Recherche du CHUL et Université Laval, 2705, boul. Laurier, G1V 4G2, QC, Québec, Canada.
Rouxs Arch Dev Biol. 1992 May;201(3):157-168. doi: 10.1007/BF00188714.
Segment polarity genes define the cell states that are required for proper organization of each metameric unit of the Drosophila embryo. Among these, the gooseberry locus has been shown to be composed of two closely related genes which are expressed in an overlapping single-segment periodicity. We have used specific antibodies raised against the protein product of the gooseberry proximal (gsb-p) gene to determine the spatial distribution of this antigen in wild type embryos, and to monitor the effects of segment polarity mutants on the pattern of the gsb-p protein distribution. We find that the gsb-p protein accumulates beneath each posterior axonal commissure in the progeny of neuroblasts deriving from the epidermal compartments of wingless (wg) and engrailed (en) expression. The results of this analysis support the idea that gsb-p has a specific role in the control of cell fates during neurogenesis, and indicate that en and wg provide critical positional cues to define the domain in which gsbp will be activated. Furthermore, these data suggest that, in order to be expressed in the embryonic CNS, gsb-p may preliminarily require activity of the gooseberry-distal gene in the epidermis.
体节极性基因定义了果蝇胚胎每个体节单位正确组织所需的细胞状态。其中，醋栗基因座已被证明由两个密切相关的基因组成，它们以重叠的单节段周期性表达。我们使用针对醋栗近端（gsb-p）基因的蛋白质产物产生的特异性抗体，来确定这种抗原在野生型胚胎中的空间分布，并监测体节极性突变体对gsb-p蛋白分布模式的影响。我们发现，gsb-p蛋白在源自无翅（wg）和 engrailed（en）表达的表皮区室的神经母细胞后代的每个后轴突连合下方积累。该分析结果支持了gsb-p在神经发生过程中对细胞命运控制具有特定作用的观点，并表明en和wg提供了关键的位置线索来定义gsb-p将被激活的区域。此外，这些数据表明，为了在胚胎中枢神经系统中表达，gsb-p可能初步需要表皮中醋栗远端基因的活性。
