Figure 2.

Positioning of individual AQP4 tetramers and OAPs in astrocytes is affected by intracellular and extracellular proteins. Agrin and laminin, components of the basal lamina, attach to α-dystroglycan, which forms a complex with β-dystroglycan that stretches through the plasma membrane. In the cytoplasm, it interacts with dystrophin, which binds to F-actin at one end and to α-dystrobrevin at the other end. α-Dystrobrevin interacts with α-syntrophin, which is directly linked to the AQP4 channel in the plasma membrane.