Intellectual Merit. Light-dependent chloroplast movements are observed in most green plants. These chloroplast movements serve as a rapid mechanism for fine-tuning photosynthetic productivity in response to changes in light intensity. For example, movement of chloroplasts to the upper and lower surfaces of leaf cells in dim light can improve light capture, whereas chloroplast movement to the sides of cells when the light intensity is high can protect them from photodamage. The project is focused on the function of several novel genes that this investigator recently identified as essential for the chloroplast movements to occur. Genetic, molecular and physiological approaches are being used to understand the molecular mechanism of chloroplast movements. The research is expected to elucidate details of the motility mechanisms responsible for chloroplast movement and provide new insight into the nature of the light signal transduction pathway involved. The findings will also reveal new insights into the basic cell biology of the complex activities of the actin cytoskeleton.
Broader Impacts. This project will provide training to the graduate and postgraduate students doing the research and to undergraduates seeking research opportunities in the lab. Because light-induced chloroplast movements can impact photosynthetic potential, knowledge gained from this research has the potential to help in development of plants with improved yield and biomass accumulation. Research findings from the work will be used in outreach activities to teach about plant science to public audiences. These include museum exhibits, public lectures, and web-based content (e.g., see http://plantsinmotion.bio.indiana.edu ).
