1. A metal switch for controlling the activity of molecular motor proteins.
- Author
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Cochran, Jared C, Zhao, Yu Cheng, Wilcox, Dean E, and Kull, F Jon
- Subjects
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KINESIN , *MOLECULAR motor proteins , *METAL ions , *HYDROLYSIS , *MICROTUBULES , *CRYSTAL structure , *CYSTEINE proteinases - Abstract
Kinesins are molecular motors that require a divalent metal ion (for example, Mg2+) to convert the energy of ATP hydrolysis into directed force production along microtubules. Here we present the crystal structure of a recombinant kinesin motor domain bound to Mn2+ and ADP and report on a serine-to-cysteine substitution in the switch 1 motif of kinesin that allows its ATP hydrolysis activity to be controlled by adjusting the ratio of Mn2+ to Mg2+. This mutant kinesin binds ATP similarly in the presence of either metal ion, but its ATP hydrolysis activity is greatly diminished in the presence of Mg2+. In human kinesin-1 and kinesin-5 as well as Drosophila melanogaster kinesin-10 and kinesin-14, this defect is rescued by Mn2+, providing a way to control both the enzymatic activity and force-generating ability of these nanomachines. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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