Grant: Discovery Grants Program - Individual

This research proposal is designed to continue our ongoing work in investigating the adaptations that take place in muscle as a result of regularly performed exercise. We use cell biology, biochemical and molecular approaches to understanding this process. A major adaptation that is well established in muscle in response to exercise is its improved ability to produce energy (ATP) within the cellular compartment called the mitochondrion. The mitochondrion is called the ""powerhouse"" of the cell, because it generates the energy required for muscle to contract, and it is important for the maintenance of good muscle metabolic health. Regularly performed physical activity (i.e. exercise) produces an increase in the mitochondrial content of muscle cells, an adaptation that results in reduced fatigue and improved metabolism at all levels of physical activity. This adaptation is known to occur across a wide range of animal species, including humans. How this takes place is not fully understood. This purpose of this proposal is to investigate what we feel are the most important, cutting-edge research questions that are currently unresolved in the process of exercise-induced mitochondrial synthesis and turnover in muscle. We investigate this at the level of gene transcription, protein translocation and the movement and assembly of mitochondria in muscle responding to either acute or chronic exercise, using animal models or muscle cells in culture. The results of our research program will have a significant impact on how we view the importance of mitochondria within the context of the muscle cell, and will allow us to revise our thinking about the cellular benefits of exercise and the role of mitochondrial turnover in muscle health.