Lipolysis regulates major transcriptional programs in brown adipocytes [3Dcultured_eWAs_RNA-seq]

ß-Adrenergic signaling is a core regulator of brown adipocyte function stimulating both lipolysis and transcription of thermogenic genes, thereby expanding the capacity for oxidative metabolism. Here we have used pharmacological inhibitors and a novel direct activator of lipolysis to acutely modulate the activity of lipases, thereby enabling us to uncover lipolysis-dependent signaling pathways downstream of ß-adrenergic signaling in brown adipocytes. We show that induction of lipolysis leads to acute induction of several gene programs and is required for transcriptional regulation by ß-adrenergic signals. Using machine-learning algorithms to infer causal transcription factors, we show that PPARs are key mediators of lipolysis-induced activation of genes involved in lipid metabolism and thermogenesis. Importantly, lipolysis also activates the unfolded protein response and regulates the core circadian transcriptional machinery independently of PPARs. Our results demonstrate that lipolysis generates important metabolic signals that exert profound pleiotropic effects on brown adipocyte transcription and function. Overall design: Isolated epididymal white adipocytes with ISO for 3 hrs in the presence and absence of lipase inhibitors and determined the effect on the transcriptome by RNA-seq analysis. Subsequently, we stimulated the mature brown adipocytes with SR-3420 for 3hrs and harvsted for RNA for RNAsequencing.