Structure/ function analyses of sarco(endo)plasmic reticulum CA2+ - ATPases : effects of oxidative stress , redox signaling and protein-protein interactions

肌（内）质网 CA2 - ATP 酶的结构/功能分析：氧化应激、氧化还原信号传导和蛋白质-蛋白质相互作用的影响

• 批准号: 311922-2010
• 负责人: Tupling, Allan
• 金额: $ 2.55万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=548558
• 关键词: Structure; function; analyses; sarco; endo

Muscle cells in our body are often exposed to a variety of stressful conditions such as heat stress or intense exercise or in association with a variety of diseases. When muscle cells are exposed to stress the calcium level inside the cells increases and it is believed that cell damage and even cell death will occur as a result of the increased cellular calcium. One major reason for the increase in calcium with stress is that the enzyme responsible for maintaining normal calcium levels in muscle, namely the Ca2+ pump, becomes damaged with stress. Therefore, it would be expected that cell damage would be reduced and survival would be increased after stress if the calcium pump could somehow be protected. We have recently shown that a protein called heat shock protein 70 (Hsp70) can protect the calcium pump in muscle during heat stress but we haven't figured out exactly how this works yet or whether other proteins in muscle might also protect the calcium pump. The goal of this project is to examine specifically how Hsp70 and two other proteins called phospholamban and sarcolipin, protect the Ca2+ pump under a wide range of stress conditions. We will manipulate the levels of the Ca2+ pump, Hsp70, phospholamban and sarcolipin in living cells using recombinant DNA technology and then expose the cells to various types of stress (i.e. heat, reactive oxygen species, etc.) followed by assessment of structural and functional damage to the Ca2+ pump. Another goal of our research is to understand what controls the amount of Hsp70 that is normally found in muscle under resting and exercise conditions. We will recruit young (<30 years) and old (>70 years) men and women for our experiments to investigate potential sex and age differences in the Hsp70 response to exercise in human skeletal muscle. This work could have important implications that extend into a number of fields (i.e. cancer and heart disease research) because protecting the Ca2+ pump could prevent increases in calcium and improve cell survival following stress.

我们体内的肌肉细胞经常暴露于各种压力条件下，例如热应激或剧烈运动或与各种疾病相关。当肌肉细胞受到压力时，细胞内的钙水平会增加，并且据信由于细胞钙增加会导致细胞损伤甚至细胞死亡。压力导致钙含量增加的一个主要原因是，负责维持肌肉中正常钙水平的酶（即 Ca2+ 泵）会因压力而受损。因此，如果钙泵能够以某种方式得到保护，预计应激后细胞损伤将会减少，存活率将会增加。我们最近证明，一种名为热休克蛋白 70 (Hsp70) 的蛋白质可以在热应激期间保护肌肉中的钙泵，但我们尚未弄清楚其具体工作原理，也不清楚肌肉中的其他蛋白质是否也可以保护钙泵。该项目的目标是专门研究 Hsp70 和另外两种蛋白质（受磷蛋白和肌磷脂）如何在各种应激条件下保护 Ca2+ 泵。我们将使用重组 DNA 技术操纵活细胞中 Ca2+ 泵、Hsp70、受磷蛋白和肌磷脂的水平，然后将细胞暴露于各种类型的应激（即热、活性氧等），然后评估 Ca2+ 泵的结构和功能损伤。我们研究的另一个目标是了解是什么控制着静息和运动条件下肌肉中通常存在的 Hsp70 的量。我们将招募年轻（<30 岁）和老年（>70 岁）的男性和女性进行实验，以研究人类骨骼肌运动中 Hsp70 反应的潜在性别和年龄差异。这项工作可能具有重要的意义，可以扩展到许多领域（即癌症和心脏病研究），因为保护 Ca2+ 泵可以防止钙的增加并提高细胞在压力后的存活率。