XK (protein)

XK (protein) is a protein that in humans is encoded by the XK gene. It is a type of membrane transport protein that plays a crucial role in the human body.

Function

The XK protein is a component of the Kell blood group system, and it is associated with the Kell glycoprotein. The Kell glycoprotein functions as an endopeptidase that cleaves peptide bonds at the C-terminal side of a phenylalanine or tyrosine residue. The XK protein is a type of transporter that likely plays a role in ion transport across membranes.

Clinical significance

Mutations in the XK gene can lead to McLeod syndrome, a rare X-linked recessive disorder characterized by hemolytic anemia, neuromuscular abnormalities, and late-onset cardiomyopathy. The syndrome is caused by a lack of the Kx antigen on red blood cells, which is due to a defect in the XK protein.

Structure

The XK protein is a type of transmembrane protein that spans the membrane of the cell. It has a large extracellular domain and a smaller intracellular domain. The protein is highly conserved in evolution, suggesting that it plays a fundamental role in cellular function.

See also

• Kell blood group system
• McLeod syndrome
• Membrane transport protein
• Gene
• Protein