Aquaporin is a membrane protein that facilitates the transport of water across cell membranes.

• Function: Selectively allows water molecules to pass in and out of cells while blocking ions and larger solutes.
• Structure: Forms tetramers, with each subunit creating a water channel.
• Types:
  • AQP1: Found in red blood cells and kidney tubules.
  • AQP2: Found in kidney collecting ducts; regulated by vasopressin.
  • AQP3:
  • AQP4: Found in the brain, helps regulate brain water balance.

Aquaporins were discovered by Peter Agre in 1992. He received the Nobel Prize in Chemistry in 2003 for this discovery.

• Wikipedia: Aquaporin
• Nobel Lecture by Peter Agre

Aquaporin 4