PNPLA3 is a triacylglycerol lipase that mediates triacylglycerol hydrolysis in adipocytes. The encoded protein, which appears to be membrane bound, may be involved in the balance of energy usage/storage in adipocytes.
The glucose-induced increase in Adpn expression could be countered by agents known to raise intracellular cAMP. In vivo, Adpn mRNA was high in white and brown adipose tissue from fed mice, but it dropped to barely detectable levels after 19 hours of fast. Refeeding for 8 hours reversed the drop in Adpn mRNA. Fas and Srebp1c mRNA exhibited a similar pattern of expression. Just after a feeding period, Zucker fa/fa obese rats showed 30- to 50-fold elevation of Adpn mRNA relative to congenic lean controls.