Structural and Calcium Regulatory Proteins in Sarcopenia

描述：(来自应用程序的逐字)我们的长期目标是确定 肌力下降的分子机制与ARE有关。 我们的总体假设是，与年龄相关的肌肉性能下降是 由于关键肌肉蛋白的细胞和分子变化。这件事的重点是 建议是肌球蛋白，肌肉中的主要收缩蛋白。我们的假设是 力量产生能力随着年龄的增长而下降是由于特定的 肌球蛋白的结构变化，由肌球蛋白的积聚引起 翻译后修饰。我们将通过执行以下操作来验证这一假设 大鼠肌球蛋白的生理、生物物理和生化研究 不同年龄的人。以下目标将使用后肢肌肉来实现 10、22周龄的大鼠。24.26.还有28个月。 目的1.确定单纤维力量产生的年龄相关差异 能力。将确定单根纤维的发力能力。 使用渗透性纤维制剂。一种敏感的微凝胶技术将是 用于鉴定肌球蛋白重链异构体的纤维含量 肌纤维型。我们假设美国的经济将会下降。 单根I型和II型纤维的发力能力随年龄的变化。目标 2.使用定点EPR波谱来确定与年龄相关的变化 肌球蛋白结构。自旋标签将被粘贴到肌球蛋白上的选定位置 头内肌肉纤维，然后EPR将被用来检测与年龄相关的 收缩过程中肌球蛋白结构的变化。EPR的优势在于它 分辨率高，可探测和量化构造展布 与肌球蛋白的弱结合和强结合中间体相对应的状态。我们 假设与年龄相关的力量生成下降是由于 肌球蛋白的强结合结构状态减少。目标3.确定 肌球蛋白中与年龄相关的翻译后化学修饰。级别 肌球蛋白中的硝基酪氨酸、巯基和羰基将被测定。我们 假设有翻译后化学物质的增加 肌球蛋白的修饰引起肌球蛋白结构的改变 导致部队产量下降。这一结果将对 了解细胞衰老的分子机制。

DESCRIPTION: (Verbatim from application) Our long-term goal is to determine the molecular mechanisms underlying the diminished performance of muscle with are. Our overall hypothesis is that the age-related decline in muscle performance is due to cellular and molecular changes in key muscle proteins. The focus of this proposal is myosin, the major contractile protein in muscle. Our hypothesis is that the decline in force-generating capacity with age is due to specific structural alterations in myosin, resulting from accumulation of post-translational modifications. We will test this hypothesis by performing physiological, biophysical and biochemical investigations of myosin from rats of different ages. The following aims will be pursued using hindlimb muscles of rats aged 10, 22. 24. 26. and 28 months. AIM 1. Determine age-related differences in single fiber force-generating capabilities. The force-generating capacity of single fibers will be determined using a permeabilized fiber preparation. A sensitive microgel technique will be used to identify myosin heavy chain isoform content of the fibers to determine muscle fiber type. We hypothesize that there will be a decline in the force-generating capacity of individual type I and type II fibers with age. AIM 2. Use site-directed EPR spectroscopy to determine age-related changes in myosin structure. Spin labels will be attached to a selected site on the myosin head within muscle fibers and then EPR will be used to detect age-related changes in myosin structure during contraction. The advantage of EPR is its high resolution, which can detect and quantitate the distribution of structural states corresponding to the weak-and strong-binding intermediates of myosin. We hypothesize that the age-related decline in force generation is a result of a decrease in the strong-binding structural state of myosin. AIM 3. Determine age-related post-translational chemical modifications in myosin. Levels of nitrotyrosine, sulfhydryls, and carbonyls in myosin will be determined. We hypothesize that there are increases in post-translational chemical modifications in myosin causing alterations in myosin protein structure resulting in decreased force production. The results will be invaluable for understanding the molecular mechanisms of cellular aging.