Topic Overview:
The dynamin-related proteins (DRPs) are a conserved family of large multi-domain GTPases that are involved in membrane remodeling events throughout the cell. Despite sharing similar domain organizations, members of the family have distinct cellular localizations and have customized roles in membrane remodeling, ranging from fusion to fission. Disruption of DRP function is associated with a wide range of pathologies, including diabetes, neurodegeneration, epilepsy, mitochondrial disorders, and aging. Ford’s laboratory is interested in structural and functional characterization of DRPs in general.
Ford and his colleagues’ recent work on Vps1, a poorly characterized member of the DRP family, revealed an unexpected role for DRPs in autophagy-related membrane remodeling. Specifically, Vps1 is required for microautophagy, which is defined by direct vacuolar/lysosomal uptake of autophagic cargoes by invagination of the vacuolar/lysosomal membrane. Microautophagy is needed for cell survival under conditions of stress and subsequent recovery. Ford shows that microautophagy is also a key regulator of TOR signaling, which plays well-established roles in growth, survival, and lifespan control. Hence, Ford and his colleagues’ findings extend the repertoire of DRP-mediated membrane remodeling into regulation of TOR signaling and cell survival.