Rapid Glucose Depletion Immobilizes Active Myosin V on Stabilized Actin Cables

SummaryPolarization of eukaryotic cells requires organelles and protein complexes to be transported to their proper destinations along the cytoskeleton [1]. When nutrients are abundant, budding yeast grows rapidly transporting secretory vesicles for localized growth and actively segregating organelles [2, 3]. This is mediated by myosin Vs transporting cargos along F-actin bundles known as actin cables [4]. Actin cables are dynamic structures regulated by assembly, stabilization, and disassembly [5]. Polarized growth and actin filament dynamics consume energy. For most organisms, glucose is the preferred energy source and generally represses alternative carbon source usage [6]. Thus, upon abrupt glucose depletion, yeast shuts down pathways consuming large amounts of energy, including the vacuolar-ATPase [7, 8], translation [9], and phosphoinositide metabolism [10]. Here we show that glucose withdrawal rapidly (