新研究：哺乳动物细胞中SIRT3对赖氨酸苯甲酰化的调节存在差异

2024年10月，中国科学院大学杭州高等研究院药学院；中国科学院上海药物研究所化学生物学国家重点实验室；南京中医药大学中药学院 (School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China ；State Key Laboratory of Chemical Biology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China；School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China) He Huang老师研究团队在《iScience.》上发表论文：

“SIRT3 differentially regulates lysine benzoylation from SIRT2 in mammalian cells"

“哺乳动物细胞中SIRT3对赖氨酸苯甲酰化的调节存在差异"

Abstract：

Lysine benzoylation (Kbz), a new type of protein post-translational modification (PTM) we discovered, has garnered significant attention.  While we initially identified SIRT2 as a debenzoylase in mammalian cells, recent findings suggest its exclusivity may be questioned.  However, other debenzoylases in mammalian cells remain underexplored.  Here, our study reveals SIRT3 as an additional debenzoylase.  Through quantitative analysis, we identified 1,075 Kbz sites in mammalian cells, with 44 specifically mediated by SIRT3 and 66 influenced by SIRT2.  Notably, SIRT3 and SIRT2 regulate distinct Kbz substrates, indicating involvement in different cellular processes.  Functional investigations demonstrated SIRT3's regulation of benzoylated protein peptidyl-prolyl cis-trans isomerase F (PPIF), where K73bz and K197bz markedly diminished interactions with the tumor suppressor p53.  Additionally, K978bz on ATP-citrate lyase (ACLY) notably inhibited its enzymatic activity.  This study not only identifies a debenzoylase and its Kbz substrates but also enhances our understanding of Kbz's biological functions.

摘要：

赖氨酸苯甲酰化（Kbz）是我们发现的一种新的蛋白质翻译后修饰（PTM），引起了人们的广泛关注。虽然我们最初在哺乳动物细胞中确定SIRT2是一种脱苯甲酰酶，但最近的研究结果表明，它的专一性可能受到质疑。然而，哺乳动物细胞中的其他脱苯甲酰酶仍未得到充分研究。在这里，我们的研究表明SIRT3是另一种脱苯甲酰酶。通过定量分析，我们在哺乳动物细胞中确定了1,075个Kbz位点，其中44个是SIRT3特异性介导的，66个是受SIRT2影响的。值得注意的是，SIRT3和SIRT2调节不同的Kbz底物，表明参与不同的细胞过程。功能研究表明SIRT3调节苯甲酰化蛋白肽酰脯氨酸顺式反式异构酶F (PPIF)，其中K73bz和K197bz显著降低了与肿瘤抑制因子p53的相互作用。此外，K978bz对atp -柠檬酸裂解酶（ACLY）的酶活性有明显的抑制作用。本研究不仅鉴定了一种脱苯甲酰酶及其Kbz底物，而且提高了我们对Kbz生物学功能的认识。

该论文中，293T和HepG2细胞的体外培养是使用Ausbian特级胎牛血清完成的。