Send to:

Choose Destination
See comment in PubMed Commons below
Nature. 1995 Nov 9;378(6553):209-12.

Movement and force produced by a single myosin head.

Author information

  • 1Department of Biology, University of York, UK.


Muscle contraction is driven by the cyclical interaction of myosin with actin, coupled to the breakdown of ATP. Studies of the interaction of filamentous myosin and of a double-headed proteolytic fragment, heavy meromyosin (HMM), with actin have demonstrated discrete mechanical events, arising from stochastic interaction of single myosin molecules with actin. Here we show, using an optical-tweezers transducer, that a single myosin subfragment-1 (S1), which is a single myosin head, can act as an independent generator of force and movement. Our analysis accounts for the broad distribution of displacement amplitudes observed, and indicates that the underlying movement (working stroke) produced by a single acto-S1 interaction is approximately 4 nm, considerably shorter than previous estimates but consistent with structural data. We measure the average force generated by S1 or HMM to be at least 1.7 pN under isometric conditions.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Nature Publishing Group
    Loading ...
    Write to the Help Desk