Recently, some research groups reported that argonaute2 (Ago2) mediated the biogenesis of erythroid miRNAs.23,24 Moreover, the methylation of Ago2 mRNA could repress miRNA expression in the process of human aging.25 Hence, we measured the protein levels of Ago2 in the total heart tissues of TAC mice at multiple time-points. This evidence concerns the gene AGO2 and persistent truncus arteriosus.