GENETIC AND MOLECULAR STUDIES OF SUPPRESSOR OF SEVENLESS

果蝇眼内神经元发育遵循非克隆机制 在那里，细胞受到微环境的指示，承担起命运 识别出的神经元。Seven less基因参与了这一过程 并调节R7感光神经元的发育。我们有 分离到一个显性的Seven less表型的第二位点抑制因子。它 被称为无七(SOS)的抑制者。我们已经绘制了这种突变的图谱， 表明这种抑制是Seven less的E4等位基因所特有的， 制造全尺寸的蛋白质产品。我们提出，突变产物 SOS基因是对sevE4蛋白缺陷的补偿， 在野生型果蝇中，Seven less基因的产物具有功能 与七分之路有关。果蝇遗传学技术 分子生物学将被用来详细描述 SOS基因。抑制者相互作用的七次函数的方面 将通过对SEVENSS等位基因的分子分析来确定 是被压制的。遗传马赛克研究将确定细胞(S) 负责抑制功能。SOS基因将被克隆并 特色化的。通过对抑制者的详细研究，我们希望获得 更好地理解通向神经元的途径 差异化。

Neuronal development in the Drosophila eye follows a non-clonal mechanism where cells are instructed by their microenvironment to take on the fate of identified neurons. The sevenless gene participates in this process and mediates the development of the R7 photoreceptor neuron. We have isolated a dominant second site suppressor of the sevenless phenotype. It is called Suppressor of sevenless (Sos). We have mapped this mutation and shown that the suppression is specific to the E4 allele of sevenless, that makes a full sized protein product. We propose that the mutant product of the Sos gene is compensating for the defect in the sevE4 protein, and that in wild type flies, the product of the sevenless gene has a function relevant to the sevenless pathway. Techniques from Drosophila genetics and molecular biology will be used for detailed characterization of the Sos gene. The aspect of sevenless function that the suppressor interacts with will be determined by molecular analysis of the sevenless allele that is suppressed. Genetic mosaic studies will identify the cell(s) responsible for the suppressor function. The Sos gene will be cloned and characterized. From a detailed study of the suppressor, we hope to obtain a better understanding of a pathway that leads to neuronal differentiation.