Defining Molecular Determinants of Type 2 Diabetes Using Quantitative Proteomics

拟议研究的目的是确定线粒体蛋白丰度和磷酸化的改变如何导致2型糖尿病（T2DM）。最近的研究将线粒体功能障碍与胰岛素抵抗联系起来。该提案的共同发起人Alan Attie博士利用遗传学来了解发展为2型糖尿病的倾向。David Pagliarini博士是该提案的发起人，他专注于线粒体功能障碍对各种疾病的贡献，并了解线粒体生物发生的基础科学。Joshua Coon博士是我最初申请的发起人，也是本提案的密切合作者，他是开发和应用质谱（MS）仪器进行蛋白质分析的领导者。从库恩小组转到帕格里亚里尼实验室开始第二个博士后，我作为我们跨学科合作团队的领导成员继续这个项目。

The objective of the proposed research is to determine how alterations in mitochondrial protein abundance and phosphorylation contribute to Type 2 Diabetes Mellitus (T2DM). Recent studies have linked mitochondrial dysfunction to insulin resistance. Dr. Alan Attie, co-sponsor of this proposal, uses genetics to understand the propensity to develop T2DM. Dr. David Pagliarini, sponsor of this proposal, focuses on the contribution of mitochondrial dysfunction to various diseases and understanding the basic science of mitochondrial biogenesis. Dr. Joshua Coon, the sponsor of my original application and a close collaborator on this proposal, is a leader in the development and application of mass spectrometry (MS) instrumentation for protein analysis. Having transition from the Coon group to start a second post-doc in the Pagliarini lab, I am continuing this project as the leading member of our interdisciplinary collaborative team. I have completed collection of an exhaustive quantitative proteomics dataset that constituted the bulk of my proposed research for this project in my original application. I observed highly reproducible alterations in protein abundance and phosphorylation in liver mitochondria in a cohort of over forty mice, which are either susceptible (B6) or resistant (BTBR) to developing T2DM when made obese. I am currently using this proteomics screen as preliminary data for hypotheses-driven targeted biological investigation. The rationale for the proposed research is that determining how phosphorylation modulates redox-regulatory proteins in obesity will open new avenues for developing therapeutic interventions for type 2 diabetes. The co-sponsoring environment will help facilitate my goal of starting an independent academic laboratory focused on utilizing proteomics and targeted biology to study redox signaling in metabolic disease. I will employ both biochemical, cell biology, and targeted proteomic approaches to carrying out the following Aims: Aim 1. Determine how the obesity-induced phosphorylation of the selenocysteine-specific elongation factor (Eefsec) regulates the production of redox-regulatory selenoproteins. I will test the hypothesis that enhanced obesity-induced phosphorylation of the non-mitochondrial isoform of Eefsec in diabetes- resistant B6 mice attenuates the production of inflammatory secreted selenoproteins without decreasing levels of key mitochondrial antioxidants, which are regulated by a mitochondrial-localized Eefsec isoform. Aim 2. Elucidate the role of obesity-induced phosphorylation of mitochondrial redox enzymes in regulating the abundance of bioactive lipophilic aldehydes. I will test the hypothesis that obesity-induced phosphorylation of dehydrogenase/reductase SDR family member 4 (Dhrs4) alters the levels of retinoid metabolites in diabetic BTBR mice through regulating the enzyme's retinal reducing activity. A parallel hypothesis I will test is that induction of aldehyde dehydrogenase 3A2 (Aldh3a2) expression and phosphorylation is a compensatory response in obesity for detoxifying reactive lipid-peroxidation products.