Don Hilgemann (University of Texas Southwestern Medical Center): From Adapter-Free Endocytosis to Plasma Membrane Expansion without Exocytosis: A physiological tango between TMEM16F and dynamin2
From Adapter-Free Endocytosis to Plasma Membrane Expansion without Exocytosis: A physiological tango between TMEM16F and dynamin2
Speakers: Don Hilgemann & Michael Fine
Institute: University of Texas Southwestern Medical Center
Seminar abstract: Cells can expand their plasma membrane (PM) laterally by unfolding membrane undulations and by exocytosis. We now describe a third mechanism involving invaginations held shut by the adapter protein, dynamin2. In multiple cell types, one-half of the PM can be sequestered in this fashion. Then, when Ca activates the lipid scramblase, TMEM16F, compartments open as anionic phospholipids escape from the cytoplasmic monolayer, neutral phospholipids enter the inner monolayer, and dynamins relax. Ca influx via mechanosensitive cation channels triggers local phospholipid scrambling and compartment opening during cell swelling.
host: Gucan Dai (daig@uw.edu) and William N. Zagotta (zagotta@uw.edu)
Recent Paper: Bricogne, C. et al. TMEM16F activation by Ca(2+) triggers plasma membrane expansion and directs PD-1 trafficking. Scientific reports 9, 619, doi:10.1038/s41598-018-37056-x (2019).