Anion exchange protein 1, erythrocyte (AE1)

Anion exchange protein 1, erythrocyte (commonly known as Band 3 or AE1), is the major membrane glycoprotein of human erythrocytes and also present in the kidney. It is a member of the solute carrier family 4 (SLC4A1) that mediates the electroneutral exchange of chloride and bicarbonate ions across the plasma membrane. This function is essential for CO₂ transport in the bloodstream and for acid-base balance in the kidney. Structurally, Band 3 is a dimer with a cytosolic N-terminal domain that interacts with the cytoskeleton (ankyrin, protein 4.2) and various red cell proteins (e.g., hemoglobin, glycolytic enzymes), and a C-terminal multi-pass transmembrane domain responsible for anion exchange. Mutations in its encoding gene SLC4A1 lead to hereditary spherocytosis, Southeast Asian ovalocytosis, and distal renal tubular acidosis. Band 3 is a known target for inhibitors such as DIDS and DEPC, but due to its vital physiological functions, therapeutic targeting presents significant safety challenges[1][3][4][5][6][8][10].

Other names

Band 3Band 3 anion transport proteinSolute carrier family 4 member 1 (SLC4A1)Anion exchanger 1AE1CD233

Inhibition of Cl⁻/HCO₃⁻ exchange activity (blockade of anion transport) Blockade of conformational changes required for transport