MOLECULAR GENETICS OF THE DROSOPHILA ZESTE LOCUS

我们提出了一种遗传和分子生物学方法， 果蝇基因zeste的研究及其与 非连锁基因座白色、双胸和十肢瘫痪，及其 参与突触依赖性基因表达（transvection）。 这些实验将利用克隆的DNA序列分离， 实验室，并显示包含所需的所有信息， 正常的表情。 首先将注意到 完成了结构和核苷酸的详细分析 野生型基因的序列。 接下来，核苷酸序列 zeste转录本的变化和改变 将确定来自野生型Zeste基因座的突变体。 的 这些研究的分辨率将通过采用 克隆DNA体外诱变产生的突变 随后通过生殖系引入果蝇基因组， 转型 这些实验应该有助于 了解zeste突变可能导致 无数的表型结果，也许定义了 与zeste的特定方面有关的基因区域 功能 为了阐明推定的蛋白质在分子中的作用， 产品的zeste轨迹，两个主要的方法将是 就业。 首先，将仔细测量 白色转录物和蛋白质产物的量和性质 zeste突变的存在作为果蝇的功能 发展 这些实验将有助于确定 目的基因zeste功能的表达阶段。 下一个是 抗体将针对抗原决定簇产生 由zeste指定。 这些抗体将用于描述 zeste基因座组织特异性和细胞内分布 产品，并探讨zeste轨迹产品的可能性， 与白色区域附近的序列特异性相互作用 已知zeste表型所需的基因座。 额外 研究将试图确定zeste的过度表达是否 导致确定的表型结果，以研究 修饰zeste表型的非连锁基因，并探索 酵母中与zeste同源的DNA序列的性质。 预计这些实验将产生重要的 与研究后生动物生物体中的基因调控有关， 以及染色体的体细胞配对 可能影响基因表达。

We propose a genetic and molecular biological approach to the study of the Drosophila gene zeste, its interactions with the unlinked loci white, bithorax, and decapentaplegic, and its involvement in synapsis-dependent gene expression (transvection). These experiments will utilize cloned DNA sequences isolated in laboratory and shown to contain all information required for normal zeste expression. Attention will first be given to the completion of a detailed analysis of the structure and nucleotide sequence of the wild-type gene. Next, nucleotide sequence changes and alterations in zeste transcripts differentiating mutant from wild-type zeste loci will be determined. The resolution of these studies will be increased by employing mutations generated by in vitro mutagenesis of cloned DNA subsequently introduced into the Drosophila genome by germ-line transformation. These experiments should aid in the understanding of the manner in which mutations at zeste can lead to a myriad of phenotypic consequences, and perhaps define regions of the gene involved in particular aspects of zeste function. To address the molecular roles played by putative protein products of the zeste locus, two major approaches will be employed. First, careful measurements will be taken of the amount and nature of white transcripts and protein products in the presence of zeste mutations as a function of Drosophila development. These experiments will help establish at which stage of the expression of the target genes zeste functions. Next, antibodies will be generated against antigenic determinants specified by zeste. These antibodies will be utilized to describe the tissue-specific and intracellular distributions of zeste locus products, and to explore the possibility that zeste locus products interact specifically with sequences in the vicinity of the white locus known to be required for the zeste phenotype. Additional studies will attempt to determine whether overexpression of zeste results in defined phenotypic consequences, to study the action of unlinked genes which modify the zeste phenotype, and to explore the nature of DNA sequences in yeast homologous to zeste. It is expected that these experiments will have an important bearing on the study of gene regulation in metozoan organisms, and of the means by which the somatic pairing of chromosomes may influence gene expression.