RT Journal Article SR Electronic T1 Pac1/LIS1 promotes an uninhibited conformation of dynein that coordinates its localization and activity JF bioRxiv FD Cold Spring Harbor Laboratory SP 684290 DO 10.1101/684290 A1 Matthew G. Marzo A1 Jacqueline M. Griswold A1 Steven M. Markus YR 2019 UL http://biorxiv.org/content/early/2019/06/27/684290.abstract AB Cytoplasmic dynein is a minus end-directed microtubule motor that transports myriad cargos in various cell types and contexts. How dynein is regulated to perform all these activities with a high degree of spatial and temporal precision is unclear. Recent studies have revealed that human dynein-1 and dynein-2 can be regulated by a mechanism of autoinhibition, whereby intermolecular contacts limit motor activity. Whether this autoinhibitory mechanism is conserved throughout evolution, whether it can be affected by extrinsic factors, and its precise role in regulating cellular dynein activity remain unknown. Here, we use a combination of negative stain EM, single molecule motility assays, genetic, and cell biological techniques to show that the autoinhibitory conformation is conserved in budding yeast, and it plays an important role in coordinating dynein localization and function in cells. Moreover, we find that the Lissencephaly-related protein, LIS1 (Pac1 in yeast) plays an important role in regulating this autoinhibitory conformation of dynein. Specifically, our studies demonstrate that rather than inhibiting dynein motility, Pac1/LIS1 promotes dynein activity by stabilizing the uninhibited conformation, which ensures appropriate localization and activity of dynein in cells.