ACTA2 and Hepatic fibrosis: Giving further support to the conclusion that PIAS4 depletion down-regulated liver fibrosis in mice was the observation that expression levels of several pro-fibrogenic marker genes including collagen type I (Col1a1, Col1a2) and alpha smooth muscle actin (Acta2) were markedly decreased in MCD-fed mice receiving shPias4 lentivirus than those receiving SCR lentivirus (Fig. 3E,F).