Question

Describe the process of formation of a clathrin-coated vesicle on the plasma membrane during receptor mediated endocytosis.

Answer 1

Clathrin-mediated endocytosis is described as a process in which cells absorb metabolites, hormones, proteins by the formation of inward budding of the plasma membrane also called as invagination.

Process

1. Clathrin-mediated endocytosis process initiates with the cargo ligands in the luminal compartment of the vesicle that binds to receptors on the cell membrane.
2. The cargo ligand and receptor will later recruit adaptor proteins and clathrin triskelions towards outside of the cellular membrane around budding that will form.
3. Budding of the plasma membrane will initiate that will form a clathrin-coated pit.
4. Some other receptors can also nucleate a clathrin-coated pit that will allow the formation around the receptor.
5. A mature pit will be later cleaved from the plasma membrane by the use of membrane-binding and fission proteins like dynamin. This will form a clathrin-coated vesicle that will uncoats and typically fuses to a sorting endosome.
6. After the fusion, the endocytosed cargo will be sorted to lysosomal, recycling, or trafficking pathways.