Baker JE, Krementsova EB, Kennedy GG, Armstrong A, Trybus KM, Warshaw DM. Myosin V processivity: multiple kinetic pathways for head-to-head coordination.
Proc Natl Acad Sci U S A 2004;
101:5542-6. [PMID:
15056760 PMCID:
PMC397419 DOI:
10.1073/pnas.0307247101]
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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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