AQP4 is a member of the aquaporin family, which consists of integral membrane proteins that facilitate the transport of water across cell membranes. This protein is highly expressed in the CNS, particularly in the astrocyte foot processes that surround blood vessels and form the glial limiting membrane. The presence of AQP4 in these regions highlights its importance in maintaining the blood-brain barrier and in regulating the brain's extracellular space.
