As validation of in vivo efficacy of RNF5 modulation, RNF5 knockdownin F508del-CFTR transgenic mice exhibited improved intestinal absorptionand increased CFTR activity in intestinal epithelial cells, relativeto animals expressing WT-RNF5.127 Thesefindings validated RNF5 as a drug target for CF and provided the basisfor the development of RNF5-targeting molecules that could inhibitits activity. This evidence concerns the gene CFTR and cystic fibrosis.