CFTR and cystic fibrosis: Cystic fibrosis is associated with the misfolding and premature degradation of the cystic fibrosis transmembrane conductance regulator (CFTR) mutant CFTRΔF508, it has been demonstrated that RNF5 targeted CFTRΔF508 for degradation through the endoplasmic reticulum-associated degradation (ERAD) [8, 9].