Mitochondrial Acetylation and Acetylome Dynamics in Alcoholic Liver Disease assessed with Heavy Water

总结 酒精性肝病（ALD）是肝脏相关死亡的主要原因。酒精摄入与 肝线粒体蛋白的乙酰化过度和线粒体功能受损。但 线粒体乙酰化的重要性一直存在争议，因为乙酰化的化学计量较低。我们 我认为，乙酰组动力学的变化，而不是水平，是线粒体的决定因素。 功能其基本原理是肝线粒体可能通过乙酰转移对酒精诱导的应激作出反应 依赖性酶抑制（短期调节）和/或乙酰转移独立调节 蛋白质稳定性（长期调节）。为了评估这些乙酰化介导的变化的影响，我们将 使用稳定的同位素分辨的高- 分离度液相色谱-串联质谱法（LC-MS/MS）。这种方法依赖于我们的技术 这是解剖乙酰基部分和肽骨架的同位素标记的进展。乙酰化周转率为 基于乙酰基部分的标记测定。乙酰化对蛋白质稳定性的影响通过 完整天然肽和不含乙酰基部分的乙酰化肽片段的半衰期的比较。 我们将使用这种方法以及遗传和药理学工具来研究乙酰组动力学改变的作用。 在ALD小鼠肝脏中。实验将与北方俄亥俄州酒精中心合作进行（见 Nagy博士的LOS）使用建立的用Lieber-DeCarli饮食诱导的ALD小鼠模型， 肝乙酰化过度和线粒体功能障碍。目的1将确定是否酒精诱导乙酰化 改变肝线粒体蛋白和线粒体呼吸的稳定性。目标2将评估影响 酒精消耗对线粒体蛋白乙酰化周转的影响以及 乙酰转移对代谢和抗氧化酶的调节。 我们的新工具和合作专业知识将使我们能够研究酒精诱导的机制。 线粒体功能障碍该项目的完成将揭示改变乙酰化动力学的新作用， 酒精性肝脏，并帮助确定乙酰化作为治疗ALD的治疗靶点。

Summary Alcoholic liver disease (ALD) is a major cause of liver-related death. Alcohol intake is associated with hyperacetylation of hepatic mitochondrial proteins and impaired mitochondrial function. However, the significance of mitochondrial acetylation has been debated because of the low stoichiometry of acetylation. We propose that changes in acetylome dynamics, rather than levels, are the determinant of mitochondrial function. The rationale is that hepatic mitochondria may respond to alcohol-induced stress via acetyl-transfer dependent enzymatic inhibition (short-term regulation) and/or the acetyl-transfer independent regulation of protein stability (long-term regulation). To assess the impact of these acetylation-mediated changes, we will quantify mitochondrial acetylome dynamics in ALD mice liver in vivo using a stable isotope-resolved high- resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS). This method relies on our technical advancement that dissects the isotope-labeling of acetyl moiety and peptide backbone. Acetylation turnover is determined based on labeling of acetyl moiety. The effect of acetylation on protein stability is assessed by comparisons of the half-lives of the intact native peptide and acetylated peptide fragments without acetyl moiety. We will use this method and genetic and pharmacological tools to study the role of altered acetylome dynamics in ALD mice livers. Experiments will be performed in collaboration with The Northern Ohio Alcohol Center (see LOS of Dr. Nagy) using an established mouse model of ALD induced with a Lieber-DeCarli diet that results in hepatic hyperacetylation and mitochondrial dysfunction. Aim 1 will determine if alcohol-induced acetylation alters the stability of hepatic mitochondrial proteins and mitochondrial respiration. Aim 2 will assess the impact of alcohol consumption on the acetylation turnover of mitochondrial proteins and the consequence of altered acetyl transfer on regulations of metabolic and antioxidant enzymes. Our novel tools and collaborative expertise will enable us to investigate the mechanisms of alcohol-induced mitochondrial dysfunction. Completion of this project will uncover a novel role of altered acetylation dynamics in the alcoholic liver and help to identify acetylation as a therapeutic target for the treatment of ALD.