PNPLA2 and steatosis: Such limitations are especially relevant when analyzing Plin2 function in the liver, given that Plin5 binds and regulates the activity of ATGL (69), steatosis is exacerbated in Pnpla2 (ATGL)−/− mice (70), and as shown in this study, Plin5 is overexpressed in Plin2−/− livers.