Controlling kinesin motor proteins in nanoengineered systems through a metal-binding on/off switch.
A significant challenge in utilizing kinesin biomolecular motors in integrated nanoscale systems is the ability to regulate motor function in vitro. Here we report a versatile mechanism for reversibly controlling the function of kinesin biomolecular motors independent of the fuel supply (ATP). Our approach relied on inhibiting conformational changes in the neck-linker region of kinesin, a process necessary for microtubule transport. We introduced a chemical switch into the neck-linker of kinesin by genetically engineering three histidine residues to create a Zn(2+)-binding site. Gliding motility of microtubules by the mutant kinesin was successfully inhibited by >/=10 microM Zn(2+), as well as other divalent metals. Motility was successfully restored by removal of Zn(2+) using a number of different chelators. Lastly, we demonstrated the robust and cyclic nature of the switch using sequential Zn(2+)/chelator additions. Overall, this approach to controlling motor function is highly advantageous as it enables control of individual classes of biomolecular motors while maintaining a consistent level of fuel for all motors in a given system or device.
Greene
Adrienne C
AC
Biomolecular Interfaces and Systems Department, Sandia National Laboratories, PO Box 5800, MS 1413, Albuquerque, New Mexico 87111, USA.
Trent
Amanda M
AM
Bachand
George D
GD
D000818:Animals; D002413:Cations, Divalent / Q000378:metabolism; D004331:Drosophila melanogaster; D019476:Insect Proteins / Q000378:metabolism*; D016547:Kinesins / Q000378:metabolism*; D009068:Movement; D036103:Nanotechnology; D011485:Protein Binding; D015032:Zinc / Q000378:metabolism*
D002413:Cations, Divalent; D019476:Insect Proteins; D016547:Kinesins; D015032:Zinc