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Myosin VI walks "wiggly" on actin with large and variable tilting.

ABSTRACT: Myosin VI is an unconventional motor protein with unusual motility properties such as its direction of motion and path on actin and a large stride relative to its short lever arms. To understand these features, the rotational dynamics of the lever arm were studied by single-molecule polarized total internal reflection fluorescence (polTIRF) microscopy during processive motility of myosin VI along actin. The axial angle is distributed in two peaks, consistent with the hand-over-hand model. The changes in lever arm angles during discrete steps suggest that it exhibits large and variable tilting in the plane of actin and to the sides. These motions imply that, in addition to the previously suggested flexible tail domain, there is a compliant region between the motor domain and lever arm that allows myosin VI to accommodate the helical position of binding sites while taking variable step sizes along the actin filament.

SUBMITTER: Sun Y

PROVIDER: S-EPMC2683265 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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Myosin VI walks "wiggly" on actin with large and variable tilting.

Sun Yujie Y Schroeder Harry W HW Beausang John F JF Homma Kazuaki K Ikebe Mitsuo M Goldman Yale E YE

Molecular cell 20071201 6

Myosin VI is an unconventional motor protein with unusual motility properties such as its direction of motion and path on actin and a large stride relative to its short lever arms. To understand these features, the rotational dynamics of the lever arm were studied by single-molecule polarized total internal reflection fluorescence (polTIRF) microscopy during processive motility of myosin VI along actin. The axial angle is distributed in two peaks, consistent with the hand-over-hand model. The ch ...[more]

PMID: 18158894

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