Single Molecule Mechanical Studies of Actomyosin

肌动球蛋白的单分子力学研究

• 批准号: 6340386
• 负责人: HOWARD D. WHITE
• 金额: $ 4.77万
• 依托单位: EASTERN VIRGINIA MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6340386
• 关键词: British Isles; actins; adenosine triphosphate; bioenergetics; biomechanics; charge coupled device camera; chemical association; chemical chain length; chemical kinetics; electrical measurement; enzyme substrate analog; fluorescence microscopy; fluorescent dye /probe; hydrolysis; intermolecular interaction; lasers; molecular site; muscle contraction; myosins; nucleotide analog; protein structure function

Description (provided by applicant): The long term goals of this proposal are to use single molecule mechanical and fluorescence methods to study the mechanism by which the energy from ATP is converted to mechanical work by the molecular motor proteins, actin and myosin. Single molecule mechanical measurements have the advantage over traditional measurements with muscle fibers in that force, working stoke and kinetics of the interaction of a single cross-bridge with actin can be measured directly. A better understanding of the mechanism of contraction is an important step towards understanding and ameliorating the changes that occur in pathological conditions, resulting from defective contractility. Mutations in myosin are responsible for familial hypertropic cardiomyopathy, which is a major cause of cardiovascular death at ages under 40 and for the most common cause of congenital deaf-blind-ness in humans. Specific aims of the proposal are to: 1) determine the mechanical properties of cross-bridges by utilizing a series of ATP analogues that alter the rates of the hydrolysis mechanism; (2) utilize long-lived weakly-bound acto-myosin intermediates to characterize the prepower-stoke states; (3) combine single molecule mechanical and fluorescence methods to determine the temporal relationship between product release and force production.

描述（申请人提供）：本提案的长期目标是 利用单分子力学和荧光方法研究 ATP的能量被转化为机械功的机制。 分子马达蛋白，肌动蛋白和肌球蛋白。单分子力学 与传统的肌肉测量相比， 纤维在该力，工作斯托克和动力学的相互作用，一个单一的 可以直接测量与肌动蛋白的交叉桥。更好地理解 收缩机制是理解和 改善病理状况中发生的变化， 收缩性缺陷肌球蛋白的突变是导致家族性 肥厚性心肌病，这是心血管死亡的主要原因， 年龄在40岁以下，最常见的原因是先天性失明， 人类该提案的具体目标是：1）确定机械 通过利用一系列ATP类似物改变交叉桥的性质， 水解机制的速率;（2）利用长寿命的弱结合 肌动蛋白-肌球蛋白中间体，以表征前功率-冲程状态;（3） 联合收割机单分子机械和荧光方法测定 产品释放和力产生之间的时间关系。