Molly S.C. Gravett, David P. Klebl, Oliver G. Harlen, Daniel J. Read, Stephen P. Muench, Sarah A. Harris, Michelle Peckham
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引用次数: 0
Abstract
Myosin 5a (Myo5a) is a dimeric processive motor protein that transports cellular cargos along filamentous actin (F-actin). Its long lever is responsible for its large power-stroke, step size, and load-bearing ability. Little is known about the levers’ structure and physical properties, and how they contribute to walking mechanics. Using cryoelectron microscopy (cryo-EM) and molecular dynamics (MD) simulations, we resolved the structure of monomeric Myo5a, comprising the motor domain and full-length lever, bound to F-actin. The range of its lever conformations revealed its physical properties, how stiffness varies along its length and predicts a large, 35 nm, working stroke. Thus, the newly released trail head in a dimeric Myo5a would only need to perform a small diffusive search for its new binding site on F-actin, and stress would only be generated across the dimer once phosphate is released from the lead head, revealing new insight into the walking behavior of Myo5a.
期刊介绍:
Structure aims to publish papers of exceptional interest in the field of structural biology. The journal strives to be essential reading for structural biologists, as well as biologists and biochemists that are interested in macromolecular structure and function. Structure strongly encourages the submission of manuscripts that present structural and molecular insights into biological function and mechanism. Other reports that address fundamental questions in structural biology, such as structure-based examinations of protein evolution, folding, and/or design, will also be considered. We will consider the application of any method, experimental or computational, at high or low resolution, to conduct structural investigations, as long as the method is appropriate for the biological, functional, and mechanistic question(s) being addressed. Likewise, reports describing single-molecule analysis of biological mechanisms are welcome.
In general, the editors encourage submission of experimental structural studies that are enriched by an analysis of structure-activity relationships and will not consider studies that solely report structural information unless the structure or analysis is of exceptional and broad interest. Studies reporting only homology models, de novo models, or molecular dynamics simulations are also discouraged unless the models are informed by or validated by novel experimental data; rationalization of a large body of existing experimental evidence and making testable predictions based on a model or simulation is often not considered sufficient.