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Stiffness of Cargo-Motor Linkage Tunes Myosin VI Motility and Response to Load.

ABSTRACT: We examine the effect of cargo-motor linkage stiffness on the mechanobiological properties of the molecular motor myosin VI. We use the programmability of DNA nanostructures to modulate cargo-motor linkage stiffness and combine it with high-precision optical trapping measurements to measure the effect of linkage stiffness on the motile properties of myosin VI. Our results reveal that a stiff cargo-motor linkage leads to shorter step sizes and load-induced anchoring of myosin VI, while a flexible linkage results in longer steps with frequent detachments from the actin filament under load. Our findings suggest a novel regulatory mechanism for tuning the dual cellular roles of the anchor and transporter ascribed to myosin VI.

SUBMITTER: Shrivastava R

PROVIDER: S-EPMC7055456 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Stiffness of Cargo-Motor Linkage Tunes Myosin VI Motility and Response to Load.

Shrivastava Rachit R Rai Ashim A Salapaka Murti M Sivaramakrishnan Sivaraj S

Biochemistry 20190920 47

We examine the effect of cargo-motor linkage stiffness on the mechanobiological properties of the molecular motor myosin VI. We use the programmability of DNA nanostructures to modulate cargo-motor linkage stiffness and combine it with high-precision optical trapping measurements to measure the effect of linkage stiffness on the motile properties of myosin VI. Our results reveal that a stiff cargo-motor linkage leads to shorter step sizes and load-induced anchoring of myosin VI, while a flexible ...[more]

PMID: 31508940

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