AQP4
Description
The AQP4 (aquaporin 4) is a protein-coding gene located on chromosome 18.
AQP4 forms a water-specific channel, playing a crucial role in brain water homeostasis. It facilitates glymphatic solute transport, enabling normal water exchange across the blood-brain barrier. AQP4 is essential for proper cerebrospinal fluid influx into the brain cortex and parenchyma through paravascular spaces surrounding penetrating arteries, as well as for the drainage of interstitial fluid along paravenous pathways. This function is critical for the clearance of solutes from the brain's interstitial fluid, including soluble beta-amyloid peptides derived from APP. While AQP4 also plays a role in urinary water homeostasis and concentration, its contribution is considered redundant.
AQP4 is also known as MIWC, MLC4, WCH4, hAQP4.