Speaker Professor Kenneth Taylor, Department of Biological Sciences, Florida State University

Title Near Atomic Resolution cryoEM Structure of a Striated Muscle Thick Filament and its Implications for Myosin Filament Structure Across Species

Host Malcolm Irving

 

Abstract Although models for the myosin tail arrangement in striated muscle thick filaments were first proposed in the 1970's an experimental test was not possible until the "resolution revolution" in cryoEM. The first subnanometer striated muscle thick filament structure, from the large waterbug Lethocerus indicus, showed that the myosin tails were arranged in the "curved molecular crystalline layers" first proposed by John Squire in 1973. Further work has showed that the same tail arrangement with little variation occurs in two other insect species having the same type of flight muscle. Several novel features not previously described were also observed including several non-myosin proteins threaded between the myosin tails and unexpected structures at the skip residues. This lecture will attempt to tie some of this information together into some testable ideas about the role of the thick filament in muscle contraction.