Role of FA-BRCA pathway in stem cell resistance to acetaldehyde

FA-BRCA 通路在干细胞乙醛抵抗中的作用

• 批准号: 9436056
• 负责人: Silvia Balbo
• 金额: $ 26.44万
• 依托单位: FRED HUTCHINSON CANCER RESEARCH CENTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-22 至 2019-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9436056
• 关键词: Acetaldehyde; Acetylation; Affect; Alcohol consumption; Alcohols; CRISPR/Cas technology; Carcinogens; Cells; Chemicals; Cirrhosis; Collection; DNA; DNA Adducts; DNA Interstrand Crosslinking; DNA Repair; DNA Repair Pathway; Data; Deacetylase; Development; Disease; Embryo; Epithelial Neoplasms; Ethanol Metabolism; Exhibits; Failure; Fanconi Anemia-BRCA Pathway; Fanconi' s Anemia; Fetal Alcohol Syndrome; Generations; Genes; Genetic; Hereditary Disease; Hypersensitivity; Link; Malignant Neoplasms; Measures; Metabolic; Metabolism; Methods; Mitochondria; Mitochondrial DNA; Mitochondrial Proteins; Pathway interactions; Population; Production; Protein Acetylation; Proteins; Proteome; Quality Control; Regulation; Research; Resistance; Risk; Role; Sirtuins; Stem cells; Syndrome; Toxic effect; adduct; alcohol effect; aldehyde dehydrogenases; cell injury; cell type; congenital anomaly; crosslink; cytotoxicity; embryonic stem cell; hepatotoxin; implantation; mitochondrial autophagy; repaired; response

Project Summary Acetaldehyde is both an exogenous carcinogen and endogenous metabolite. While acetaldehyde formed after consumption of alcoholic beverages is well-known as a hepatotoxin and contributor to the developmental abnormalities associated with fetal alcohol syndrome, endogenous production of acetaldehyde was only recently linked to the genetic disease, Fanconi anemia. Acetaldehyde forms DNA adducts, including interstrand DNA crosslinks, repaired by the Fanconi anemia/BRCA pathway. Alcohol metabolism also induces mitochondrial autophagy, or mitophagy, as a cytoprotective mechanism. An entirely new function for Fanconi anemia/BRCA proteins in mitophagy was recently described, highlighting a potential role for the FA/BRCA in responding to acetaldehyde-induced cellular injury. Both Fanconi anemia and fetal alcohol syndrome are characterized by congenital anomalies, and Fanconi anemia and alcohol predispose to an overlapping collection of epithelial neoplasms. Cellular sensitivity to acetaldehyde is poorly understood, and is likely affected by endogenous production of acetaldehyde, metabolism, generation of covalent DNA and protein adducts, and repair pathways. Naïve and primed embryonic stem cells represent pre- and post-implantation pluripotent populations in the developing embryo. We demonstrate that naïve embryonic stem cells are strikingly tolerant of 1 mM acetaldehyde, while primed embryonic stem cells are exquisitely sensitive (in fact, our collaborator, Dr. Carol Ware, uses acetaldehyde routinely to select against any primed cells that may arise during culture of naïve embryonic stem cells). In preliminary data, we show that both types of embryonic stem cell generate acetaldehyde and exhibit basal levels of acetaldehyde adducts with DNA to different degrees. Surprisingly, resistance of naïve embryonic stem cells to acetaldehyde is not diminished by inhibition of acetaldehyde-metabolizing aldehyde dehydrogenases. In this proposal, we will investigate the mechanisms of differential acetaldehyde resistance in embryonic stem cells. Specifically, in Aim 1 we will utilize sensitive DNA adductomic profiling to examine the role of the Fanconi anemia/BRCA DNA repair pathway or mitochondrial DNA repair in acetaldehyde resistance. In Aim 2, we will investigate the regulation of the mitophagic response to acetaldehyde by the FA/BRCA pathway. Acetaldehyde inhibits sirtuin 3, the mitochondrial deacetylase, most likely by depleting its NAD+ substrate, leading to a hyperacetylated mitochondrial proteome. Acetylation inhibits mitophagy. We will determine whether the FA/BRCA pathway reduces mitochondrial protein acetylation, thus enabling quality control via mitophagy. The proposed research will generate important new information for understanding cellular responses to acetaldehyde, both in the context of alcohol consumption and genetic syndromes of acetaldehyde hypersensitivity.

项目概要 乙醛既是外源性致癌物，又是内源性代谢产物。 众所周知，饮用酒精饮料会产生肝毒素，并导致发育异常 与胎儿酒精综合症有关，内源性乙醛的产生直到最近才与遗传病联系起来， 范可尼贫血。乙醛形成 DNA 加合物，包括链间 DNA 交联，由范可尼修复。 贫血/BRCA 途径也会诱导线粒体自噬或线粒体自噬，作为一种细胞保护剂。 最近描述了范可尼贫血/BRCA 蛋白在线粒体自噬中的全新功能，强调了这一机制。 FA/BRCA 在应对乙醛诱导的细胞损伤中的潜在作用 范可尼贫血和胎儿酒精。 综合征的特点是先天性异常，范可尼贫血和酒精容易导致重叠集合 上皮性肿瘤。 人们对细胞对乙醛的敏感性知之甚少，并且可能受到内源性乙醛产生的影响 乙醛、代谢、共价 DNA 和蛋白质加合物的生成以及修复途径。 我们证明，胚胎干细胞代表发育中胚胎中植入前和植入后的多能细胞群。 幼稚胚胎干细胞对 1 mM 乙醛具有惊人的耐受性，而引发的胚胎干细胞则对 1 mM 乙醛具有惊人的耐受性。 敏感（事实上，我们的合作者 Carol Ware 博士经常使用乙醛来选择可能出现的任何引发细胞） 在初始数据中，我们表明两种类型的胚胎干细胞都会产生。 令人惊讶的是，乙醛与DNA加合物的基础水平不同程度地表现出幼稚的抵抗力。 胚胎干细胞对乙醛的吸收不会因乙醛代谢乙醛脱氢酶的抑制而减少。 在本提案中，我们将研究胚胎干细胞中差异乙醛抵抗的机制。 具体来说，在目标 1 中，我们将利用敏感的 DNA 加合组分析来检查 Fanconi 贫血/BRCA 的作用 在目标 2 中，我们将研究乙醛抵抗中的 DNA 修复途径或线粒体 DNA 修复。 FA/BRCA 途径对乙醛的线粒体自噬反应 乙醛会抑制线粒体的 Sirtuin 3。 脱乙酰酶，很可能是通过耗尽其 NAD+ 底物，导致线粒体蛋白质组过度乙酰化。 我们将确定 FA/BRCA 途径是否会降低线粒体蛋白乙酰化。 通过线粒体自噬实现质量控制拟议的研究将为理解提供重要的新信息。 在饮酒和乙醛遗传综合征的背景下细胞对乙醛的反应 超敏反应。