Gary C. Sieck, Ph.D., studies the neural control of breathing muscles, including the diaphragm and airway smooth muscle.
Dr. Sieck has developed an extensive array of state-of-the-art physiological and biomedical engineering techniques to explore the interaction between motor neurons in the nervous system and the muscle fibers they innervate.
These techniques include real-time confocal microscopy to image changes in intracellular calcium in response to stimulation, and uses confocal microscopy and three-dimensional reconstruction to evaluate structural remodeling and localize protein expression. Sieck and his colleagues are using laser capture microdissection and single cell RT-PCR techniques to examine changes in phrenic motor neuron mRNA expression. His group has also developed quantitative electrophoretic techniques to explore changes in contractile protein expression in single muscle fibers and the relationship between contractile protein content and both mechanical and energetic properties of muscle fibers. In particular, he has examined the expression of different isoforms of myosin heavy chain, which form cross-bridges with actin during force generation and contraction, and are the site of ATP hydrolysis. Thus, plasticity in the essential linkages between structure, intracellular calcium regulation, mechanical and energetic properties of muscle fibers is being comprehensively explored.
Dr. Sieck's research has been continuously funded by multiple grants from the National Institutes of Health for more than 30 years.