Exocytosis

Exocytosis releases substances from a cell when intracellular vesicles fuse with the plasma membrane and discharge their contents outside it. It also adds vesicle membrane to the cell surface.

SNARE proteins: Membrane proteins that drive vesicle fusion by assembling into tight complexes across opposing membranes. SNARE complexes pull vesicle and plasma membranes together to enable fusion.
Secretory vesicle: A membrane-bound compartment that stores or transports cellular products for release outside the cell. Secretory vesicles carry cargo to the plasma membrane for exocytosis.
Synaptic vesicle: A small vesicle in a neuron that stores neurotransmitters for release at a synapse. Synaptic vesicles release neurotransmitters by calcium-triggered exocytosis.
Plasma membrane: The lipid bilayer that encloses a cell and regulates exchange with its surroundings. Each full vesicle fusion adds vesicle membrane to this boundary.
Rab proteins: A family of small GTPases that regulate membrane trafficking, including vesicle movement, recognition, and docking. Rab proteins help direct secretory vesicles to the correct cellular destination.
Golgi apparatus: A membrane-bound organelle that modifies, sorts, and packages proteins and lipids for delivery. Many secretory vesicles bud from the Golgi after cargo sorting.
Neurotransmitter release: The secretion of chemical messengers from neurons into synapses to communicate with target cells. It is a rapid, tightly timed use of exocytosis.
Synaptic transmission: Communication between neurons or between a neuron and target cell through synaptic signals. Exocytosis releases the neurotransmitters that initiate chemical synaptic transmission.
Tethering proteins: Proteins that capture and position transport vesicles near their target membranes before fusion. Tethering helps bring secretory vesicles into range of fusion machinery.
Endoplasmic reticulum: A membrane network that synthesizes proteins and lipids and supplies them to other cellular compartments. Secreted proteins often enter this network before Golgi processing and vesicle packaging.

Linked from 24 pages