Chen Yang, Liu Lin, Calhoun Ryan, Cheng Lan, Merrick David, Steger David J, Seale Patrick
bioRxiv. 2024 Jul 31:2024.07.31.605689. doi: 10.1101/2024.07.31.605689.
Adipocyte lipolysis controls systemic energy levels and metabolic homeostasis. Lipolysis is regulated by post-translational modifications of key lipolytic enzymes. However, less is known about the transcriptional mechanisms that regulate lipolysis. Here, we identify the transcriptional factor interferon regulatory factor-2 binding protein 2 (IRF2BP2) as a repressor of adipocyte lipolysis. Deletion of IRF2BP2 in primary human adipocytes increases lipolysis without affecting glucose uptake, whereas IRF2BP2 overexpression decreases lipolysis. RNA-seq and ChIP-seq analyses reveal that IRF2BP2 directly represses several lipolysis-related genes, including ( , hormone sensitive lipase), which encodes the rate-limiting enzyme in lipolysis. Adipocyte-selective deletion of in mice increases expression and free fatty acid levels, resulting in elevated adipose tissue inflammation and glucose intolerance. Altogether, these findings demonstrate that IRF2BP2 restrains adipocyte lipolysis and opens new avenues to target lipolysis for the treatment of metabolic disease.
脂肪细胞的脂解作用控制着全身能量水平和代谢稳态。脂解作用受关键脂解酶的翻译后修饰调控。然而,关于调节脂解作用的转录机制,人们了解较少。在此,我们确定转录因子干扰素调节因子2结合蛋白2(IRF2BP2)是脂肪细胞脂解作用的一种抑制因子。在原代人脂肪细胞中缺失IRF2BP2可增加脂解作用,而不影响葡萄糖摄取,而IRF2BP2的过表达则降低脂解作用。RNA测序和染色质免疫沉淀测序分析表明,IRF2BP2直接抑制多个脂解相关基因,包括( ,激素敏感脂肪酶),该基因编码脂解作用中的限速酶。在小鼠中脂肪细胞选择性缺失 可增加 表达和游离脂肪酸水平,导致脂肪组织炎症加剧和葡萄糖不耐受。总之,这些发现表明IRF2BP2抑制脂肪细胞脂解作用,并为靶向脂解作用治疗代谢性疾病开辟了新途径。