Band 3 anion transport protein

Band 3 anion transport protein, also known as anion exchanger 1 (AE1) or band 3 or SLC4A1 (solute carrier family 4 member 1), is a protein that in humans is encoded by the SLC4A1 gene. It plays a significant role in the exchange of chloride ions and bicarbonate ions across the plasma membrane of cells, particularly in red blood cells.

Function

Band 3 anion transport protein is an integral membrane protein found primarily in the plasma membrane of red blood cells, where it functions as an anion exchanger. It is involved in the chloride-bicarbonate exchange process, which is vital for the cell to regulate its pH and volume.

The protein is also found in the kidney, where it aids in the reabsorption of bicarbonate ions into the bloodstream. This is crucial for maintaining the body's acid-base balance.

Structure

The Band 3 anion transport protein is a large protein with a complex structure. It is composed of two major domains: a transmembrane domain and a cytoplasmic domain. The transmembrane domain is responsible for the exchange of anions, while the cytoplasmic domain interacts with other proteins and plays a role in regulating the protein's function.

Clinical significance

Mutations in the SLC4A1 gene can lead to a variety of diseases, including hereditary spherocytosis, Southeast Asian ovalocytosis, and hereditary elliptocytosis. These conditions are characterized by abnormalities in the shape and function of red blood cells, leading to hemolytic anemia.

In addition, Band 3 anion transport protein is a major target of naturally occurring autoantibodies in autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus.

See also

• Anion exchange protein
• Solute carrier family