BIOPHYSICS AND ENZYMOLOGY OF KINESIN MOVEMENT

驱动蛋白运动的生物物理学和酶学

• 批准号: 2628344
• 负责人: JEFF GELLES
• 金额: $ 31.39万
• 依托单位: BRANDEIS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2628344
• 关键词: biomechanics; cell motility; chemical conjugate; conformation; enzyme activity; enzyme structure; intracellular transport; kinesin; microtubules; protein structure function; site directed mutagenesis

Kinesin is a mechanoenzyme that drives microtubule-based intracellular organelle transport processes. Kinesin couples a free-energy-liberating chemical reaction (the hydrolysis of ATP) to a cycle of mechanical processes that move the enzyme molecules and attached organelles along microtubules. We want to characterize the cycle of mechanical processes by which kinesin moves and to determine how these processes are coupled to the reactions of ATP hydrolysis. We have developed novel experimental systems that allow us to directly monitor nanometer-scale mechanical processes, domain movements, and chemical steps in single isolated kinesin molecules using light microscope-based instruments. Intracellular organelle transport by kinesin and kinesin homologs plays an essential role in the physiology of eukaryotic cells. Its functions include transport of materials, chromosome and nuclear movements in mitosis/meiosis, and morphogenesis of membranous organelles. To explore these functions at the molecular level we will: Characterize the conformational changes in the kinsin alpha-helical coiled-coil neck domain that are required for processive motility along microtubules. Test the hand-over-hand hypothesis for the kinesin movement mechanism Detect and characterize the power stroke of an isolated kinesin head domain. The experiments will combine single-molecule biophysics techniques with conventional enzymology methods including protein chemical modification, site-directed mutagenesis, and chemical kinetics techniques.

肌动蛋白是一种机械酶，驱动微管为基础的细胞内