@article{92e07156ccdc4c8aaa75ccf46266160b,
title = "A posttranslational modification of the mitotic kinesin Eg5 that enhances its mechanochemical coupling and alters its mitotic function",
abstract = "Numerous posttranslational modifications have been described in kinesins, but their consequences on motor mechanics are largely unknown. We investigated one of these—acetylation of lysine 146 in Eg5—by creating an acetylation mimetic lysine to glutamine substitution (K146Q). Lysine 146 is located in the α2 helix of the motor domain, where it makes an ionic bond with aspartate 91 on the neighboring α1 helix. Molecular dynamics simulations predict that disrupting this bond enhances catalytic site–neck linker coupling. We tested this using structural kinetics and single-molecule mechanics and found that the K146Q mutation increases motor performance under load and coupling of the neck linker to catalytic site. These changes convert Eg5 from a motor that dissociates from the microtubule at low load into one that is more tightly coupled and dissociation resistant—features shared by kinesin 1. These features combined with the increased propensity to stall predict that the K146Q Eg5 acetylation mimetic should act in the cell as a “brake” that slows spindle pole separation, and we have confirmed this by expressing this modified motor in mitotically active cells. Thus, our results illustrate how a posttranslational modification of a kinesin can be used to fine tune motor behavior to meet specific physiological needs.",
keywords = "Acetylation, Kinesin, Mitosis, Molecular motor",
author = "Muretta, {Joseph M.} and Reddy, {Babu J.N.} and Guido Scarabelli and Thompson, {Alex F.} and Shashank Jariwala and Jennifer Major and Monica Venere and Rich, {Jeremy N.} and Belinda Willard and Thomas, {David D.} and Jason Stumpff and Grant, {Barry J.} and Gross, {Steven P.} and Rosenfeld, {Steven S.}",
note = "Funding Information: ACKNOWLEDGMENTS. We thank Dr. Xin-Qiu Yao (University of Michigan) for valuable discussions and simulation analysis assistance. This work was supported by American Heart Association Grant 14SDG20480032 (to J.M.M.); NIH Grants AR032961 (to D.D.T.), GM121491 (to J.S.), GM070862 (to B.J.G.), GM123068 (to S.P.G.), GM102875 (to S.S.R.), and NS073610 (to S.S.R.); and Susan G. Komen Grant CCR16377648 (to J.S.). The Orbitrap Elite instrument used in this study was purchased via NIH Shared Instrument Grant 1S10RR031537-01. Funding Information: We thank Dr. Xin-Qiu Yao (University of Michigan) for valuable discussions and simulation analysis assistance. This work was supported by American Heart Association Grant 14SDG20480032 (to J.M.M.); NIH Grants AR032961 (to D.D.T.), GM121491 (to J.S.), GM070862 (to B.J.G.), GM123068 (to S.P.G.), GM102875 (to S.S.R.), and NS073610 (to S.S.R.); and Susan G. Komen Grant CCR16377648 (to J.S.). The Orbitrap Elite instrument used in this study was purchased via NIH Shared Instrument Grant 1S10RR031537-01.",
year = "2018",
month = feb,
day = "20",
doi = "10.1073/pnas.1718290115",
language = "English (US)",
volume = "115",
pages = "E1779--E1788",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
publisher = "National Academy of Sciences",
number = "8",
}