USP6 and idiopathic pulmonary fibrosis: A 6,200-bp of wild-type (WT) human proximal α6-promoter reporter and 3 mutated promoter reporters harbouring mutations at the specific AP-1-binding DNA sequences, TRE1 (−4,848 to −4,854 nt), TRE2 (−2,873 to −2,879 nt) or both TRE1 and TRE2, were transfected into IPF lung myofibroblasts (Fig. 1b).