Two-gate mechanism for phospholipid selection and transport by type IV P-type ATPases

摘要

The defining feature of a cell is the incredibly thin sheet of membrane that demarcates the intracellular and extracellular milieus. This, cell membrane, also known as a plasma membrane, has a lipid component that provides a barrier to the passage of polar or charged molecules and a protein component that allows passage of privileged molecules to make the membrane selectively permeable. Phospholipids are critical building blocks of the plasma membrane, and these amphipathic molecules pack together side by side to form a two-layered sheet. The polar phospholipid headgroups in each leaflet face outward to interact with water, and the hydrophobic fatty acyl chains face the interior of the bilayer structure.