Mechanical and functional properties of single motor molecules.

Abstract

We sumrnarize the mechanical and functional properties of a motormolecule of muscle studied with a new type of an in vitro motility assay system and a multi-imaging microscope system. First, supercoiling of an actin filament is shown, suggesting that the filament moves forward like a right-handed screw. Second, we describe the unbinding force and the lifetime of a rigor bond between a single myosin molecule and an actin filament measured by using optical tweezers. From these results, the mechanism of sliding and force generation of the motor molecule is discussed.