What is the process of exocytosis?
Posted December 18, 2020
Exocytosis is the process by which intracellular vesicles fuse with the plasma membrane and release their contents into the extracellular fluid. The steps of exocytosis include the following:
- Trafficking – vesicles carrying content are transported to the plasma membrane using motor proteins and the cytoskeleton.
- Tethering – once the vesicles have reached the plasma membrane Rab proteins on the vesicle recognize and link to tethering proteins on the plasma membrane.
- Docking – v-SNARE proteins on the vesical bind to complimentary t-SNARE proteins on the plasma membrane.
- Priming – this step occurs only in regulated exocytosis in which the cell membrane undergoes modifications to facilitate exocytosis.
- Fusing – v-SNARE and t-SNARE proteins tightly wrap around each other bringing the vesical into contact with the plasma membrane which forces them to fuse together.