Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.4.4 (kinesin)
 5,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Kinesin is a molecular motor that transports organelles along microtubules. This enzyme has two identical 7-nm-long motor domains, which it uses to move between consecutive tubulin binding sites spaced 8 nm apart along a microtubular protofilament. The molecular mechanism of this movement, which remains to be elucidated, may be common to all families of motor proteins. In this study, a high-resolution optical-trap microscope was used to measure directly the magnitude of abrupt displacements produced by a single kinesin molecule transporting a microscopic bead. The distribution of magnitudes reveals that kinesin not only undergoes discrete 8-nm movements, in agreement with previous work [Svoboda, K., Schmidt, C. F., Schnapp, B. J. & Block, S.M. (1993) Nature (London) 365, 721-727], but also frequently exhibits smaller movements of about 5 nm. A possible explanation for these unexpected smaller movements is that kinesin's movement from one dimer to the next along a protofilament involves at least two distinct events in the mechanical cycle.
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PMID:Detection of sub-8-nm movements of kinesin by high-resolution optical-trap microscopy. 870 Aug 58

Kinesin-5 family members cross-link and slide parallel microtubules of opposite polarity, an activity that is essential for the formation of a bipolar spindle during mitosis. In this issue, Kapitein et al. (Kapitein, L.C., B.H. Kwok, J.S. Weinger, C.F. Schmidt, T.M. Kapoor, and E.J.G. Peterman. 2008. J. Cell Biol. 182:421-428) demonstrate that microtubule cross-linking triggers the conversion of kinesin-5 motility from a diffusive mode to a directional mode, initiating antiparallel microtubule sliding.
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PMID:Activation of mitotic kinesin by microtubule bundling. 1867 12