Abstract

Leucine Rich Repeat Kinase 2 (LRRK2) is the most commonly mutated gene in familial Parkinsons disease. LRRK2 is proposed to function in membrane trafficking and co-localizes with microtubules. We report the 3.5[A] structure of the catalytic half of LRRK2, and an atomic model of microtubule-associated LRRK2 built using a reported 14[A] cryo-electron tomography in situ structure. We propose that the conformation of LRRK2s kinase domain regulates its microtubule interaction, with a closed conformation favoring binding. We show that the catalytic half of LRRK2 is sufficient for microtubule binding and blocks the motility of the microtubule-based motors kinesin and dynein in vitro. Kinase inhibitors that stabilize an open conformation relieve this interference and reduce LRRK2 filament formation in cells, while those that stabilize a closed conformation do not. Our findings suggest that LRRK2 is a roadblock for microtubule-based motors and have implications for the design of therapeutic LRRK2 kinase inhibitors.