Myosin V processivity: multiple kinetic pathways for head-to-head coordination.

Josh E Baker; Elena B Krementsova; Guy G Kennedy; Amy Armstrong; Kathleen M Trybus; David M Warshaw

doi:10.1073/pnas.0307247101

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Myosin V processivity: multiple kinetic pathways for head-to-head coordination.

Josh E Baker·Elena B Krementsova·Guy G Kennedy·Amy Armstrong·Kathleen M Trybus·David M Warshaw

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Abstract

Myosin V, a double-headed molecular motor, transports organelles within cells by walking processively along actin, a process that requires coordination between the heads. To understand the mechanism underlying this coordination, processive runs of single myosin V molecules were perturbed by varying nucleotide content. Contrary to current views, our results show that the two heads of a myosin V molecule communicate, not through any one mechanism but through an elaborate system of cooperative mechanisms involving multiple kinetic pathways. These mechanisms introduce redundancy and safeguards that ensure robust processivity under differing physiologic demands.

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Adenosine Diphosphate Adenosine Triphosphate Animals Cell Line Kinetics Luminescent Proteins Mice Microscopy, Fluorescence Models, Molecular Molecular Motor Proteins Myosin Type V Recombinant Proteins Spodoptera Journal Article Research Support, U.S. Gov't, P.H.S.

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Josh E Baker, Elena B Krementsova, Guy G Kennedy, Amy Armstrong, Kathleen M Trybus, David M Warshaw. 2004-03-31. Myosin V processivity: multiple kinetic pathways for head-to-head coordination.. https://doi.org/10.1073/pnas.0307247101

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