Chapter 13: Intercellular Membrane Traffic

Exocytosis

Exocytosis

The secretory pathway delivers newly synthesized proteins, carbohydrates, and lipids either to the plasma membrane or extracellular space.

Endocytosis

The cells remove plasma membrane components and deliver them to internal compartments called endosomes, from where they can be recycled to the same or different regions of the plasma membrane or be delivered to lysosomes for degradation.

Clathrin coated vesicle

Mediates transport from the Golgi apparatus and from the plasma membrane.

COPI-coated vesicle

Mediate transport from the ER and from the Golgi cisternae.

COPII coated vesicle

Mediate transport from the ER and from the Golgi cisternae.

PIP-binding proteins

It helps regulate vesicle formation and other steps in the control of vesicle traffic.

BAR domains

Bind to and impose their shape on the underlying membrane via electrostatic interactions with the lipid head groups.

The golgi apparatus

It modifies the many proteins and lipids that it receives from the ER and then distributes them to the plasma membrane, lysosomes, and secretory vesicles.

Lysosomes

Lysosomes are membrane-enclosed organelles.

Transcytosis

Both receptor and ligand are transferred to a different plasma membrane domain, causing the ligand to be released at a different surface from where it originated, a process called transcytosis.