Characterizing the calcium dependent regulation of plant myosins
Our lab is primarily interested in understanding how plants use calcium signal transduction to regulate various cellular events. In animal cells, links between calcium signalling and cytoskeletal activity have been well documented. For example, a major component of the animal cytoskeleton is the acto-myosin complex, where myosin motor-domain proteins “walk” processively along actin filaments and function in a range of important events including muscle contraction, chromosomal rearrangements, and many other processes. Calcium signalling is linked to animal myosin function through the binding of the canonical calcium sensor, calmodulin, to myosin neck regions where it functions as part of the ‘lever’ mechanism in myosin walking. In plants, much less in known about the biochemical properties and physiological roles of myosins. Arabidopsis possesses 17 myosin isoforms divisible into two classes based upon predicted structural differences; class VIII and XI. Although these plant myosins have not been well studied, emerging evidence suggests roles in events such as organelle remodeling and movement, gravotropic response, immune response, and cell expansion. Thus, myosins represent an interesting link between cytoskeletal activity and calcium signal transduction in plants. Surprisingly, evidence for an interaction between calmodulin and myosins in plants is not well established. My project aims to explore questions addressing how plant myosins use calcium sensors to regulate their activity. I will outline my research plan and progress to date drawn from a variety of biochemical, genetic, and physiological approaches.
11:30-12:30 BioSci Rm. 3110