CFTR proteins help maintain fluid balance
 

The cystic fibrosis transmembrane conductance regulator (CFTR) gene tells our cells how to make CFTR proteins.¹ This gene provides the instructions that get passed to other parts of the cell where the CFTR protein is made.

Once CFTR proteins have been processed and folded correctly inside the cell, they are transported to the cell surface (membrane).

CFTR proteins are found at the surface of cells in many parts of the body, including the lungs, sweat glands, intestines, pancreas, sinuses, and reproductive system.¹ Here, they act like channels, with gates that open and close to control the flow of water and particles such as chloride ions in and out of cells.^1,2

CFTR proteins in a normal cell

Salt, water, and mucus

By controlling the flow of ions in and out of cells, CFTR proteins help make sure that there is the right balance of salt and water in our organs. The correct balance of salt and water is needed to help keep mucus, a slippery substance produced naturally by the body, thin and watery. Mucus covers and protects the lining of our airways, digestive system, reproductive system, and other organs and tissues in the body.

 
Here is an example of how mucus works to protect organs in the body:

• The cells of your airway surfaces are covered in fine hair-like projections called cilia
• Cilia are constantly working to brush away thin, watery mucus containing trapped dirt and germs
• This process sweeps mucus out towards the windpipe, where it is either coughed out or swallowed

So you see, it’s important that mucus stays thin and watery so that your organs can function normally.¹ In people who have cystic fibrosis, their mucus becomes thick and sticky because their CFTR proteins don't work properly.