1681-P: RNA Binding Protein HuR Is Essential for Adaptive Thermogenesis

Abstract

Brown adipose tissue (BAT) plays a key role in the regulated production of heat in response to cold temperatures, known as adaptive thermogenesis. While the transcriptional mechanisms underlying the thermogenic function of BAT has been widely studied, the role of posttranscriptional processes in BAT thermogenesis remain largely unexplored. RNA binding proteins are central to the control multiple aspects of posttranscriptional RNA biology. Here, we identify brown fat HuR as a critical regulator of adaptive thermogenesis. Mice with adipocyte-specific HuR deletion (AKO) were unable to increase energy expenditure in response to a cold challenge, resulting in marked hypothermia. HuR AKO mice housed at thermoneutrality also failed to increase energy expenditure upon beta-3 adrenoreceptor agonist treatment, indicating a defect in thermogenic BAT. HuR-deleted brown adipocytes displayed impaired mitochondrial respiration under β-adrenergic stimulation. RNA sequencing data revealed that loss of HuR led to downregulation of genes associated with TCA cycle, β-oxidation, and mTORC1 signaling in BAT. Our findings reveal an essential role for RNA binding protein HuR in thermogenic programs of the brown adipocyte and highlight the importance of posttranscriptional processes in BAT thermogenesis. Disclosure K.Park: None. S.Choi: None. J.Suh: None.