GENETIC STUDIES OF NON-ERYTHROID SPECTRIN

将在果蝇模型系统中分析血影蛋白功能 黑腹果蝇。 血影蛋白是一种膜相关细胞骨架蛋白 在红细胞形状的确定中起着关键作用。 血影蛋白在非红系细胞中也发挥着未知但重要的作用。 由于我们最近的工作已经确定了 α-血影蛋白 突变体，我们处于能够直接评估的独特位置 血影蛋白在非红系细胞中的功能。 结合生物化学、分子遗传学和经典方法 遗传分析，我们将测试血影蛋白功能的各种假设 在细胞、发育和有机体的非红细胞组织中 水平。 将产生β-血影蛋白突变体，并且这些突变体与 最近发现的α-血影蛋白突变体将被用于 研究血影蛋白在体内的功能。 表型分析将确定 完全缺乏功能性血影蛋白的影响；马赛克 分析将确定血影蛋白缺失对选定的影响 发展阶段。 该表型信息将用于设计 使用血影蛋白 DNA 结构拯救无效突变体的实验 将测试特定方面的细胞或发育作用 血影蛋白组织，例如膜结合或血影蛋白链 长度。 尽管血影蛋白亚型几乎存在于所有人类细胞中， 血影蛋白缺陷的神经和一般健康后果 非红系细胞中的表达才刚刚开始被探索。 的 拟议的实验将提供对血影蛋白的深入了解 在非红细胞中的作用。

Spectrin function will be analyzed in a model system, Drosophila melanogaster. Spectrin is a membrane-associated cytoskeletal protein that plays a key role in the determination of erythrocyte cell shape. spectrin also plays unknown, but essential, roles in non-erythroid cells. As a result of our recent work that has identified alpha-spectrin mutants, we are in the singular position of being able to directly assess the functions of spectrin in non-erythroid cells. Using a combination of biochemical, molecular genetic, and classical genetic analyses, we will test various hypotheses for spectrin function in non-erythroid tissue at the cellular, developmental and organismal level. Beta-spectrin mutants will be produced and these, together with recently identified alpha-spectrin mutants, will be utilized to investigate spectrin function in vivo. Phenotype analysis will determine the effects of the complete absence of functional spectrin; mosaic analysis will determine the effects of spectrin absence at selected developmental stages. This phenotype information will be used to design experiments that rescue null mutants with spectrin-DNA constructs that will test the cellular or developmental role of a specific aspect of spectrin organization, such as membrane binding, or spectrin chain- length. Although spectrin isoforms are present in nearly all human cells, the neurological and general health consequences of defective spectrin expression in non-erythroid cells are only beginning to be explored. The proposed experiments will provide an in-depth understanding of spectrin's role in non-erythroid cells.