Regulation of nuclear migration

描述（由申请人提供）： 典型的真核细胞的细胞核位于一个确定的区域，并通过活跃的过程维持在那里。因此，核位置的变化通常受到高度调节，并在发育和细胞中发挥重要作用。尽管核迁移的普遍性，相对较少的是知道在高等真核生物的遗传学和细胞生物学的这一过程。本研究的长期目标是确定核迁移的机制，并了解其在发育过程中的调节，使用果蝇作为模型系统。核迁移涉及一个进化上保守的途径，通过微管运动细胞质动力蛋白。果蝇nudC（DnudC）和果蝇Lisl（DLisl）基因在这一过程中具有重要的调节作用，而动力蛋白对于卵母细胞核的运动和锚定是必不可少的。我们建议使用分子和生物化学的方法来研究动力蛋白功能受核迁移途径中的基因调控的机制。这些研究将提供重要的见解如何在高等真核生物的核迁移的调节，并帮助了解动力蛋白，一个关键的微管依赖电机的活性和特异性可以调制。人类LIS 1的突变导致胚胎发育过程中神经元迁移失败，导致严重的智力迟钝和过早死亡。此外，动力蛋白运动成分的错义突变导致人类运动神经元疾病和进行性运动神经元变性，强调了确定这些无处不在的运动复合体如何调节的临床相关性。这项建议的三个具体目标是：1.为了研究DLisl在调节动力蛋白运动活性中的作用：我们将研究DLisl如何使用分子，遗传和生物化学方法以及直接测量体内运动活性的灵敏测定来影响动力蛋白功能。2.为了确定DnudC的生物学功能：我们将研究DnudC的作用，DnudC是DLisl的潜在调节剂，并对我们在DnudC中分离的突变体进行表型分析。3.为了理解DnudC功能的机制基础：将使用遗传和结构/功能分析来检查DLisl/DnudC与DnudC作用的机制基础之间的调节相互作用。

DESCRIPTION (provided by applicant): The nucleus of the typical eukaryotic cell is located at a defined region and maintained there through active processes. Consequently changes in nuclear position are often highly regulated and play important developmental and cellular roles. Despite the ubiquity of nuclear migration, relatively little is known about the genetics and cell biology of this process in higher eukaryotes. The long-term objective of this research is to determine the mechanisms underlying nuclear migration and to understand its regulation during development, using Drosophila as a model system. Nuclear migration involves an evolutionarily conserved pathway that acts through the microtubule motor cytoplasmic dynein. The Drosophila nudC (DnudC) and Drosophila Lisl (DLisl) genes have important regulatory roles in this process and dynein is essential for movement and anchoring of the oocyte nucleus. We propose to study the mechanism by which dynein function is regulated by genes in the nuclear migration pathway using molecular and biochemical approaches. These studies will provide significant insights into how nuclear migration is regulated in a higher eukaryote and help in understanding how the activity and specificity of dynein, a key microtubule dependent motor can be modulated. Mutations in human LIS1 result in failure of neuronal migration during embryogenesis causing severe mental retardation and premature death. In addition, missense mutations in dynein motor components cause human motor neuron disease and progressive motor neuron degeneration, underscoring the clinical relevance of determining how these ubiquitous motor complexes are regulated. The three specific aims of this proposal are: 1. To investigate the role of DLisl in regulating dynein motor activity: We will examine how DLisl affects dynein function using molecular, genetic and biochemical approaches as well as a sensitive assay that directly measures motor activity in vivo. 2. To determine the biological function of DnudC: We will investigate the role of DnudC, a potential regulator of DLisl and carry out a phenotypic analysis of mutants we have isolated in DnudC. 3. To understand the mechanistic basis of DnudC function: Genetic and structure/function analysis will be used to examine regulatory interactions between DLisl/DnudC and the mechanistic basis of DnudC action.