ACTA1 and autosomal dominant polycystic kidney disease: We also found that knockdown of p68 decreased the mRNA levels of fibronectin, α-SMA and collagen-1 in Pkd1-mutant PN24 cells and Pkd1 null MEK cells (Figure 7), which suggested that upregulation of p68 might promote renal fibrosis by upregulating fibrotic markers in ADPKD.