ANALYSIS OF NEMATODE SEX DETERMINATION

一个生物体如何决定两种不同的性途径中的哪一种 遵循差异化是发展的根本问题。 in C. 线虫，一种自由生活的土壤线虫，X染色体与 常染色体决定了生物体是否发育成一个自我复制体， 雌雄同体（2A：2X）或雄性（2A：1X）。 此外，一组常染色体 对染色体平衡有反应的基因被认为是 雌雄同体或雄性的发育。 1.我们的目标之一是确定C。elegans评估了X 染色体到常染色体以及这种测量如何影响 性别决定基因和剂量补偿基因下游， 通路 一种方法是从遗传学角度，将男性和两性人隔离开来 已知与剂量有关的基因的致命突变和抑制因子 赔偿 第二种方法是进行描述性分析， 细胞水平，中间性动物，由突变或 通过改变X剂量 本说明将提供一个更广泛的框架， 考虑改变正确评估的后果 X：A的比例。 因为性别分化是由染色体决定的， 组成，通常需要施加进一步的机制以确保 性染色体上的基因表达在不同的 性别 2.另一个目的是了解剂量机制 赔偿 我们的方法是从基因和生化角度分析 已知影响X连锁基因表达并识别新基因的基因座 这一过程中所涉及的基因座。 生化分析包括化验 X连锁基因在动物中的表达与怀疑改变 剂量补偿，以确定是否，事实上，他们做的。 在 此外，该分析还涉及涉及以下基因座的分子克隆： 剂量补偿

How an organism determines which of two alternative pathways of sexual differentiation to follow is a fundamental problem in development. In C. elegans, a free-living soil nematode, the ratio of X chromosomes to sets of autosomes determines whether the organism develops into a self-fertilizing hermaphrodite (2A:2X) or a male (2A:1X). In addition, a set of autosomal genes responsive to the chromosome balance has been identified as essential for either hermaphrodite development or male development. 1. One of our aims is to determine how C. elegans assesses the ratio of X chromosomes to autosomes and how this measurement affects the expression of sex-determining genes and dosage-compensating genes downstream in the pathway. One approach is a genetical one, isolating male and hermaphrodite lethal mutations and suppressors of genes known to be involved in dosage compensation. A second approach is to perform a descriptive analysis at the cellular level, of intersexual animals, induced either by mutation or by altering X dosage. This description will provide a broader framework in which to think about the consequences of altering the correct assessment of the X:A ratio. Because sexual differentiation is determined by the chromosomal composition, it is often necessary to impose a further mechanism to insure that expression of genes on sex chromosomes is kept equal in the different sexes. 2. another aim is to gain an understanding of the mechanism of dosage compensation. Our approach is to analyze genetically and biochemically loci known to affect the expression of X-linked genes and to identify new loci involved in this process. The biochemical analysis involves assaying X-linked gene expression in animals with mutations suspected to alter dosage compensation in order to determine if, in fact, they do. In addition, the analysis involves the molecular cloning of loci involved in dosage compensation.