Eye Development: Molecular Genetics of Nuclear Migration

拟对果蝇复眼感光细胞中发育调节的核迁移所需的基因和基因产物进行表征。核迁移在动物发育中具有普遍重要性。例如，人类大脑的障碍，Lissephy，是神经核团在大脑发育过程中未能适当迁移的结果。此外，果蝇对果蝇的光感受器核迁移是必不可少的。因此，将被识别和研究的基因和蛋白质与人类发育和疾病直接相关。核迁移也是一个需要理解的重要现象，因为它与真核发育中的其他关键过程有关系。许多对核迁移很重要的蛋白质也是运输其他细胞器、确定细胞极性和细胞内形态发生定位所必需的。这项研究提出了四个具体目标。首先是对Klarsicht的结构/功能分析，Klarsicht是一种光感受器核迁移所需的蛋白质。表达部分Klarsicht蛋白的转基因果蝇将被用于将亚细胞定位、蛋白质结合和细胞器迁移功能与蛋白质结构相关联。第二个目标是克隆和鉴定egk1基因，它和klarsicht一样，是光感受器核迁移所必需的。第三，针对各种蛋白质的抗体将被用来将四个核迁移基因klarsicht、egk1、BicD和DLIS-1排序到一个途径中。此外，Klarsicht和Egk1蛋白之间的物理相互作用的可能性将通过体内和体外测试进行探索。最后，将使用各种不同的遗传筛选方法来确定klarsicht/egk1途径中的其他基因。

It is proposed to characterize the genes and gene products required for developmentally regulated nuclear migrations in photoreceptors of the Drosophila compound eye. Nuclear migration is of universal importance in animal development. For example, the human brain disorder, Lissencephaly, is the result of neural nuclei failing to migrate appropriately during brain development. Moreover, the Drosophila homolog of the human Lissencephaly gene, Lis1, is essential for photoreceptor nuclear migrations in Drosophila. Thus, the genes and proteins that will be identified and studied are directly relevant to human development and disease. Nuclear migration is an important phenomenon to understand also because of its relationship to other critical processes in eukaryotic development. Many of the proteins important for nuclear migration are also required for the transport of other organelles, establishment of cell polarity, and morphogen localization within the cell. There are four specific goals of the research proposed. The first is a structure/function analysis of Klarsicht, a protein required for photoreceptor nuclear migration. Transgenic flies expressing partial Klarsicht proteins will be used to correlate subcellular localization, protein binding, and organelle migration functions with protein structure. The second aim is to clone and characterize the egk1 gene, which like klarsicht, is essential for photoreceptor nuclear migration. Thirdly, antibodies to a variety of proteins will be used to order four nuclear migration genes, klarsicht, egk1, BicD and DLis-1, into a pathway. In addition, the possibility of physical interactions between Klarsicht and Egk1 proteins will be explored using in vivo and in vitro assays. Finally, a variety of different genetic screening approaches will be used to identify additional genes in the klarsicht/egk1 pathway.