The force generated by a single kinesin molecule against an elastic load - PubMed (original) (raw)

The force generated by a single kinesin molecule against an elastic load

E Meyhöfer et al. Proc Natl Acad Sci U S A. 1995.

Abstract

To probe the mechanism by which the motor protein kinesin moves along microtubules, we have developed a highly sensitive technique for measuring the force exerted by a single motor molecule. In this technique, one end of a microtubule is attached to the tip of a flexible glass fiber of calibrated stiffness. The other end of the microtubule makes contact with a surface sparsely coated with kinesin. By imaging the tip of the glass fiber on a photodiode detector, displacement of the microtubule by kinesin through as little as 1 nm can be detected and forces as small as 1 pN resolved. Using this force-fiber apparatus we have characterized the mechanical output of this molecular motor. The speed at which a molecule of kinesin moved along the surface of a microtubule decreased linearly as the elastic force was increased. The force required to stop a single kinesin molecule was 5.4 +/- 1.0 pN (mean +/- SD; n = 16), independent of the stiffness of the fiber, the damping from the fluid, and whether the ATP concentration was high or low.

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References

    1. Proc Natl Acad Sci U S A. 1993 Dec 15;90(24):11653-7 - PubMed
    1. Nature. 1993 Jul 29;364(6436):457-9 - PubMed
    1. Nature. 1994 Mar 10;368(6467):113-9 - PubMed
    1. Cell. 1994 Jun 3;77(5):773-84 - PubMed
    1. J Biol Chem. 1994 Jun 10;269(23):16493-501 - PubMed

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