Researchers have discovered a peptide in scorpion venom that may hold the key to understanding and controlling cystic fibrosis and other secretory diseases. The novel peptide, called GaTx1, can control the movement of ions and water out of cells by interacting with a crucial chloride channel that is commonly mutated in patients with cystic fibrosis. Chloride channels are crucial for secretion in many epithelial tissues, but little has been known about their structures and mechanisms. Researchers do know that chloride channels open to allow millions of chloride ions to travel through them and out of epithelial cells. This movement creates an osmotic gradient that allows water to flow.