In vivo regulation of bi-directional transport

双向运输的体内调节

• 批准号: 6760049
• 负责人: STEVEN P GROSS
• 金额: $ 33.12万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6760049
• 关键词: Drosophilidae; biological transport; biophysics; dynein ATPase; gene mutation; immunoprecipitation; intermolecular interaction; lipid transport; mass spectrometry; microtubules; protein protein interaction; protein structure function; technology /technique development; western blottings; yeast two hybrid system

DESCRIPTION (provided by applicant): Recent biophysical studies have made great progress in clarifying the function of single molecular motors in vitro. However, in vivo molecular function is far more complicated than these in vitro studies predict: contrary to the uni-directional motion observed in vitro, many vesicles or other cargos move bidirectionally along microtubules, frequently reversing their direction of travel. Nonetheless, transport can be regulated, so that the cargo moves-on average-to the right place. To understand how such transport is regulated requires the development of new tools capable of quantifying-in vivo-the motion of individual cargos with high temporal and spatial resolution. The research develops such biophysical tools, and combines them with genetics and biochemistry to investigate the function of motors or motor complexes in vivo. Specifically, bi-directional motion of lipid droplets in early Drosophila embryos is investigated. The work can be conceptually divided into two complimentary approaches. The first, the biophysical characterization of the effects of mutations, uses optical tweezers and particle tracking and analysis to determine the specific physical role of proteins in the transport pathway. One goal is to test a theoretical framework hypothesizing the existence of a complex with certain functions, and place each protein within this framework. The second approach employs biochemical techniques to identify additional proteins involved in the regulation of transport, and determine relevant interactions between the different proteins. This information will clarify at the molecular level how the biophysically determined functions come about, and will directly investigate the hypothesized complex. The function of the proteins identified in the biochemical approaches will be directly investigated using the biophysical assays. Bi-directional transport is directly related to public health: viruses such as herpes spread through cells in a bi-directional manner; many important cargos like mitochondria and endosomes move bi-directionally. Further, mutation in some of the genes investigated here, such as Lisi, lead to human birth defects. Finally, a better understanding of transport might allow the design of new drug delivery systems.

描述（由申请人提供）：最近的生物物理研究在阐明单分子电机在体外的功能方面取得了重大进展。然而，体内分子功能比这些体外研究预测的要复杂得多：与在体外观察到的单向运动相反，许多囊泡或其他cargos沿微管上双向移动，经常逆转其旅行方向。但是，可以调节运输，以使货物平均移动到正确的位置。为了了解如何调节这种运输，需要开发能够量化体内运动的新工具 - 具有高时空和空间分辨率的单个货物的运动。该研究开发了这种生物物理工具，并将它们与遗传学和生物化学结合在一起，以研究体内电动机或运动复合物的功能。 具体而言，研究了早期果蝇胚胎中脂质液滴的双向运动。这项工作可以从概念上分为两种免费的方法。首先，使用光学镊子和粒子跟踪和分析来确定蛋白质在传输途径中的特定物理作用。一个目标是测试一个理论框架，假设具有某些功能的复合物的存在，并将每个蛋白质放置在此框架内。第二种方法采用生化技术来鉴定参与转运调节的其他蛋白质，并确定不同蛋白质之间的相关相互作用。该信息将在分子水平上阐明生物物理确定的功能如何产生，并将直接研究假设的复合物。在生化方法中确定的蛋白质的功能将直接使用生物物理测定法直接研究。 双向运输与公共卫生直接相关：诸如疱疹之类的病毒以双向方式通过细胞传播；线粒体和内体等许多重要的符号在双向上移动。此外，这里研究的一些基因（例如LISI）的突变导致人类的先天缺陷。最后，对运输的更好理解可能允许设计新药输送系统。