Basal cell adhesion molecule

Basal Cell Adhesion Molecule (BCAM), also known as Lutheran antigen or LU, is a protein that in humans is encoded by the BCAM gene. BCAM is a member of the immunoglobulin superfamily and was first identified as an antigen on the surface of red blood cells.

Structure

BCAM is a type I transmembrane protein with an extracellular region composed of five immunoglobulin-like domains. The extracellular region is followed by a single transmembrane domain and a short cytoplasmic tail. The cytoplasmic tail contains a conserved tyrosine-based sorting signal that directs the protein to the basolateral surface of epithelial cells.

Function

BCAM functions as a cell adhesion molecule, mediating adhesion of red blood cells to the extracellular matrix component laminin alpha 5. This interaction is thought to be involved in the maintenance of red blood cell shape and membrane stability. BCAM may also play a role in tumor metastasis and inflammation.

Clinical significance

Alterations in BCAM expression have been associated with a variety of diseases, including sickle cell disease, cancer, and kidney disease. In sickle cell disease, increased BCAM expression on red blood cells has been linked to increased adhesion and vaso-occlusion. In cancer, BCAM has been found to be overexpressed in several types of tumors, including breast cancer and colorectal cancer, and may contribute to tumor progression and metastasis. In kidney disease, BCAM expression has been found to be increased in the glomerulus in conditions such as diabetic nephropathy.

See also

• Cell adhesion
• Immunoglobulin superfamily
• Laminin
• Sickle cell disease
• Cancer
• Kidney disease