Sandbox Reserved 1353

Composed of 1480 amino acids in 5 domains, each connected by a nucleotide binding domain. There are 6 alpha helices and 2 trans-membrane domains.

Function

The protein regulates transport of bicarbonate and chloride ions. Important for fluid and osmotic homeostasis. The Chloride channel only opens when the R domain is phosphorylated. It also protects against pathogens by regulation the pH of airway surfaces.

Disease

When the protein isn't functional it causes Cystic Fibrosis (CF). The gene is autosomal recessive. CF prevents successful excretion of wastes in many organs. Less functional proteins may result in sterility in males.

Relevance

The protein is crucial for ion circulation in epithelial cells, with lack of function leading to serious disease.

Structural highlights

The nbd1 domain is altered in CF patients, due to deletion of residue Phe-508 which results in a severe loss of function. Mutation at any of the below sites confers resistance to salmonella to the cell. These mutations also prevent diarrhea from Cholera in mice.