To further understand how active NHE1 increases OPN expression in cardiomyocytes, we measured the expression of the phosphorylated and total proteins of ERK 1/2 (S4 Fig), Akt (S4 Fig) and RSK (Fig 5A) following 24 hours of infection with the active NHE1 adenovirus. This evidence concerns the gene AKT1 and infection.