Conformation and dynamics of the kinase domain drive subcellular location and activation of LRRK2

Schmidt, S. H.; Weng, J.-H.; Aoto, P. C.; Boassa, D.; Mathea, S.; Silletti, S.; Hu, J.; Wallbott, M.; Komives, E. A.; Knapp, S.; Herberg, F. W.; Taylor, S. S.

doi:10.1101/2020.07.13.198069

bioRxiv · 10.1101/2020.07.13.198069

Conformation and dynamics of the kinase domain drive subcellular location and activation of LRRK2

Schmidt, S. H.·Weng, J.-H.·Aoto, P. C.·Boassa, D.·Mathea, S.·Silletti, S.·Hu, J.·Wallbott, M.·Komives, E. A.·Knapp, S.·Herberg, F. W.·Taylor, S. S.

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Abstract

In a multi-tiered approach, we explored how Parkinsons Disease-related mutations hijack the finely tuned activation process of Leucine-Rich Repeat Kinase 2 (LRRK2) using a construct containing the ROC, Cor, Kinase and WD40 domains (LRRK2RCKW). We hypothesized that the N-terminal domains shield the catalytic domains in an inactive state. PD mutations, type-I LRRK2 inhibitors, or physiological Rab GTPases can unleash the catalytic domains while the active kinase conformation, but not kinase activity, is essential for docking onto microtubules. Mapping solvent accessible regions of LRRK2RCKW employing hydrogen-deuterium exchange mass spectrometry (HDX-MS) revealed how inhibitor binding is sensed by the entire protein. Molecular Dynamics simulations of the kinase domain elucidated differences in conformational dynamics between wt and mutants of the DYG{psi} motif. While all domains contribute to regulating kinase activity and spatial distribution, the kinase domain, driven by the DYG{psi} motif, coordinates domain crosstalk and serves as an intrinsic hub for LRRK2 regulation.

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Schmidt, S. H., Weng, J.-H., Aoto, P. C., Boassa, D., Mathea, S., Silletti, S., Hu, J., Wallbott, M., Komives, E. A., Knapp, S., Herberg, F. W., Taylor, S. S.. 2020-07-14. Conformation and dynamics of the kinase domain drive subcellular location and activation of LRRK2. https://doi.org/10.1101/2020.07.13.198069

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