ELLIPSOMETRY STUDIES OF CROSSBRIDGE MECHANISMS IN MUSCLE

肌肉跨桥机制的椭圆测量研究

• 批准号: 3155451
• 负责人: YIN YEH
• 金额: $ 12.37万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 1980
• 资助国家: 美国
• 起止时间: 1980-04-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3155451
• 关键词: birefringences; conformation; electron microscopy; laser spectrometry; muscle; muscle contraction; muscle proteins; myofibrils; sarcomeres; striated muscles

The studies outline in this proposal are directed towards providing additional insights into the mechanism of cross-bridge force generation in muscle cells. Non-invasive laser diffraction methods, with an emphasis on the changes of the optical polarization properties upon the interaction of light with the muscle fiber, is the technique chosen. The complete characterization of the optical polarization property known as the technique of ellipsometry, provides for the determination of both the phase and the amplitudes of the electric field components after its interaction. The amplitude information specifically singles out the intrinsically anisotropic elements of the basic muscle structural unit, the sarcomere. As such, time evolution studies of the changes in amplitudes monitor the orientational and intrinsic dynamics of anisotropic elements within the sarcomere. Predominently, these are the myosin rods: light meromyosin and subfragment 2. Since this region of the sarcomeric structure is undetected by x-ray diffraction methods and unable to a labelled by extrinsic probes, the ellipsometry technique provides an important complementary link. The phase information provides additional information about the contractile apparatus. Here, the phase shift measured in ellipsometry experiments contains both intrinsic as well as form contributions. In this proposal, the method of separation of intrinsic and form information, using simultaneously obtained amplitude data, is outlined. This additional separation of contributing parts gives this method added advantage over the technique of transmission birefringence, which also contain both anisotropic and phase information, but is inseparable. The sequence of activity outlined in this proposal will focus on: skinned fibers studies; myosin extracted, subfragment I reconstituted systems; and intact fibers under isometric tetanus and quick release conditions.

本提案中概述的研究旨在提供 对跨桥力产生机制的进一步认识， 肌肉细胞 非侵入式激光衍射方法，重点是 光偏振特性的变化 光与肌肉纤维，是技术的选择。 完整的 光学偏振特性的表征被称为 椭圆偏振技术，提供了确定相位 以及在其相互作用之后的电场分量的幅度。 振幅信息具体地挑出固有的 基本肌肉结构单位肌节的各向异性成分。 因此，对振幅变化的时间演化研究监测 内各向异性元素的取向和内在动力学 肌节 主要是肌球蛋白杆：轻肌球蛋白和 亚片段2. 由于这一区域的肌节结构未被发现 通过X-射线衍射方法并且不能被外来探针标记， 椭圆偏振技术提供了一个重要的补充环节。 的 相位信息提供了关于收缩的附加信息， 设备. 这里，在椭圆偏振实验中测量的相移 既有内在的贡献，也有形式的贡献。 在这项提案中， 分离内在信息和形式信息的方法，使用 同时获得的振幅数据，概述。 该附加 贡献部分的分离使这种方法比传统方法具有更多的优点。 透射双折射技术，它也包含了 各向异性和相位信息，但不可分割。 的序列 本提案中概述的活动将侧重于：结皮纤维研究; 肌球蛋白提取，亚片段I重建系统;和完整的纤维 在等长破伤风和快速释放条件下。