vesiclemembrane

Vesicle membrane refers to the lipid bilayer that encloses a vesicle, a small, membrane-bound compartment used for intracellular transport, storage, or secretion. In cells, the vesicle membrane consists primarily of a phospholipid bilayer with embedded proteins, cholesterol, and glycolipids. It defines the vesicle lumen, protects cargo, and interacts with cytosolic and target membranes to regulate trafficking.

The membrane's composition influences curvature, fusion potential, and permeability. Integral and peripheral proteins perform functions such as cargo selection, docking, fusion, and signaling. Lipids such as phosphoinositides and cholesterol modulate membrane properties, including bending rigidity and domain organization. The vesicle membrane also often contains proton pumps or ion channels that help maintain luminal pH and ionic conditions.

Vesicles bud from donor membranes (endoplasmic reticulum, Golgi, plasma membrane) or form through endocytosis, with coat protein complexes like COPI, COPII, or clathrin driving budding. Targeting relies on Rab GTPases and SNARE fusion machinery, allowing vesicles to fuse with appropriate acceptor membranes and release their contents.

Different vesicle types have distinct membranes. Transport vesicles, synaptic vesicles, endosomes, and lysosomal vesicles each carry characteristic proteins and lipids that support their specific roles in trafficking, neurotransmission, or degradation.

In biotechnology, artificial vesicles such as liposomes or polymeric vesicles mimic natural vesicle membranes and are used to deliver drugs or genes. Design focuses on stability, permeability, and biocompatibility.

The term vesiclemembrane is nonstandard; in most literature the term vesicle membrane or vesicular membrane is used. See also vesicle, lipid bilayer, SNARE, endocytosis, exocytosis.