[Cholesterol and lipid rafts in the biological membranes. Role in the release, reception and ion channel functions]

Abstract

Traditionally, membrane protein molecules that form ion channels, transporters, pumps, signaling complexes, machine of exo- and endocytosis is assigned as the main players of the cellular processes. Recently, the findings that indicate the importance of lipids in regulating of cell physiology are accumulated. Attention is attracting to cholesterol molecule because it can directly interact with different proteins and together with sphingolipids to form membrane microdomains (lipid rafts). Many receptors (for neurotransmitters, hormones, growth factors), signaling proteins and proteins involved in vesicular and ion transport are concentrated in the lipid rafts. Changes in stability and structure of rafts cause dramatic cellular dysfunction. In the review the current views on lipid variants that make up the biological membrane, the distribution of cholesterol, the organization and the formation of lipid rafts and caveolae are described. Accent is made on researches that focus on the significance of lipid rafts in the extra- and intracellular signaling, neurotransmitters release, receptor and ion channels function at the excitable cells.