MOLECULAR STUDIES OF RETINAL DEGENERATION IN DROSOPHILA

该项目的总体目标是重点关注新产生的 果蝇视网膜变性的插入突变体 黑腹菌实现这一目标的战略包括最近的一项 开发的诱变和筛选程序，利用P-转座 包含载体的元件，称为“增强子陷阱”。具体目标是 研究视网膜变性的细胞和分子基础 使用以下方法。首先，获得含有 P-转座子插入，并筛选细胞系的：1）LacZ表达， 光感受器; 2）ERG对正常视觉生理的破坏 分析; 3）视网膜变性的证据。第二，细胞遗传学 将确定P-转座子插入的位置，并将影响 基因将被克隆并进行详细的分子表征。 为了确保克隆的DNA确实与突变的基因相对应， 将进行与克隆的DNA的遗传互补。我们#W然后 重点是表征由突变定义的基因产物，以及 作为视网膜变性的生物化学和生理学解剖。 最后，将评估基因表达的发育程序， 该基因及其编码产物的系统发育分布 测定这些方法的结合可能会导致 视网膜变性的表征，以及提供重要的 关于感光细胞的组成部分如何发挥作用的信息， 是一体化的。 该项目是遗传性视网膜病变的更大兴趣的一部分， 导致进行性视网膜变性的疾病， 失明视网膜色素变性（RP）是这种疾病的一个例子， 人类然而，由于难以获得人RP眼 组织，许多工作已经在动物模型中进行。的复杂性 人类RP退化表明，每一个可能有不同的遗传 化学基础。因此，预计 这项研究将与至少一种疾病有关。

The overall objective of this project is to focus on newly generated insertional mutants which display retinal degeneration in Drosophila melanogaster. The strategy for accomplishing this goal involves a recently developed mutagenesis and screening procedure that utilizes P-transposable element containing vectors, called "enhancer trap". The specific aims are to study the cellular and molecular basis for the retinal degeneration using the following approaches. First, obtain lines of flies containing P-transposon insertions, and screen the lines for: 1) LacZ expression in the photoreceptors; 2) disruption of normal visual physiology by ERG analysis; and 3) evidence )f retinal degeneration. Second, the cytogenetic location of the P-transposon insertion will be determined and the effected gene will be cloned and subjected to a detailed molecular characterization. To ensure that the cloned DNA indeed corresponds to the mutated gene, genetic complementation with the cloned DNA will be carried out. We #W then focus on characterizing the gene product defined by the mutation, as well as a biochemical and physiological dissection of the retinal degeneration. Finally, the developmental program for gene expression will )e assessed and the phylogenetic distribution of the gene and its encoded products determined. A combination of these approaches is likely to lead to a characterization of the retinal degeneration, as well as provide important information on how the components of the photoreceptor cells function and are integrated. This project is part of a larger interest in genetically inherited retinal diseases that result in progressive retinal degeneration and eventual blindness. Retinitis pigmentosa (RP) is an example of such a disease in humans. However, due to the difficulty in obtaining human RP ocular tissues, much work has been carried out in animal models. The complexity of human RP degenerations suggest that each one may have a distinct genetic and chemical basis. Therefore, it is expected that results arising from this study will be relevant to at least one of the diseases.