The Candida albicans acetylome in fungal virulence

真菌毒力中的白色念珠菌乙酰化组

• 批准号: 9333188
• 负责人: NEERAJ CHAUHAN
• 金额: $ 39.75万
• 依托单位: RBHS-NEW JERSEY MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-17 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9333188
• 关键词: Acetylation; Acetylesterase; Acetyltransferase; Affect; Antifungal Agents; Bioinformatics; Biology; Candida; Candida albicans; Candidiasis; Cell physiology; Chromatin; Communicable Diseases; DNA Repair; DNA Repair Pathway; Data; Deacetylase; Defect; Dissection; Enzymes; Eukaryota; Filament; Foundations; Fungal Drug Resistance; Gene Expression Regulation; Gene Targeting; HAT1 gene; Histone Acetylation; Histones; Human; Individual; Joints; Knowledge; Left; Lysine; Malignant Neoplasms; Mediating; Microbial Biofilms; Mission; Mitochondria; Modification; Molecular; Molecular Genetics; Morphogenesis; Mutation Analysis; Nonhomologous DNA End Joining; Organism; Outcome; Oxidative Stress; Pathogenesis; Pathogenicity; Pathology; Pathway interactions; Physiology; Play; Positioning Attribute; Post-Translational Protein Processing; Protein Acetylation; Proteins; Proteomics; Public Health; Publications; RNA Processing; Regulation; Research; Role; Testing; Therapeutic; United States National Institutes of Health; Untranslated RNA; Virulence; Work; base; cell growth; drug discovery; fungus; genetic approach; genome-wide; histone modification; human disease; insight; member; mitochondrial metabolism; non-histone protein; novel; protein function; public health relevance; reverse genetics; transcriptome sequencing

 DESCRIPTION (provided by applicant): Lysine acetylation is one of the most prominent post-translational modifications (PTM) of proteins and has been recognized to play a key role in regulation of gene expression by histone modification and modulation of chromatin function. Despite impressive advances in our understanding of lysine acetyltransferases (KATs) and lysine deacetylases (KDACs) during the last decades, the role of reversible lysine acetylation in fundamental cellular processes in physiology and pathology from cancer to infectious diseases still remains poorly understood. In particular, the dissection of chromatin and non-chromatin functions of individual KATs/KDACs members still represents a major scientific challenge. For example, there is compelling evidence that lysine acetylation of proteins modulates virulence of pathogenic fungi such as Candida albicans, but the underlying mechanisms have remained largely unexplored. Understanding these mechanisms is all the more important because the recognition motifs of C. albicans acetyltransferases KATs are unique to the fungal kingdom and thus represent promising targets for antifungal drug discovery. The central hypothesis of the proposed research is that protein acetylation plays pivotal roles in controlling the cellular physiology and virulence of C. albicans. We formulated this hypothesis based on our preliminary data indicating that lysine acetylation is an abundant form of PTM in C. albicans. Furthermore, our previous work has implicated C. albicans Hat1, a paradigmatic histone lysine acetylase, in DNA damage repair, morphogenesis, biofilm formation, antifungal drug resistance, and virulence. However, the roles of several other lysine acetyltransferase enzymes in this organism have remained unknown. Our preliminary studies have also implicated acetylation at two specific lysine residues (K654 and K655) of Lig4, an important protein involved in Non-Homologous End Joining (NHEJ)-dependent DNA repair and modulating morphogenesis and virulence of C. albicans. Furthermore, new preliminary RNA-seq data suggest that Hat1 has important roles in mitochondrial function, as well as in the processing and regulation of non-coding RNAs (ncRNA). The main objective in our joint application is therefore to identify and characterize the histone and non-histone target genes of C. albicans Hat1 and to investigate its ill-defined role in regulation of mitochondrial function and a possible role in the NHEJ DNA repair. Guided by the preliminary data, we expect to test our central hypothesis and to accomplish the objectives of this application by pursuing the following three Specific Aims: 1) To identify and characterize both histone and non- histone (non-chromatin) targets of Hat1. 2) To investigate the possible role of acetylation of the NHEJ DNA repair pathway in regulation of C. albicans virulence. 3) To investigate role of Hat1 in the processing of ncRNA. The payoffs of this proposal are expected to be significant because we expect to uncover novel modes of regulation of key cellular processes important for pathogenesis of C. albicans.

 描述（由申请人提供）：赖氨酸乙酰化是蛋白质最重要的翻译后修饰（PTM）之一，并已被认为在通过组蛋白修饰和染色质功能调节来调节基因表达中发挥关键作用。尽管在过去几十年中我们对赖氨酸乙酰转移酶（KAT）和赖氨酸脱乙酰酶（KDAC）的理解取得了令人印象深刻的进展，但可逆赖氨酸乙酰化在从癌症到传染病的生理学和病理学基本细胞过程中的作用仍然知之甚少。特别是，对单个 KAT/KDAC 成员的染色质和非染色质功能的剖析仍然是一项重大的科学挑战。例如，有令人信服的证据表明蛋白质的赖氨酸乙酰化可调节白色念珠菌等病原真菌的毒力，但其潜在机制在很大程度上仍未被探索。了解这些机制就显得尤为重要，因为白色念珠菌乙酰转移酶 KAT 的识别基序是真菌界所独有的，因此代表了抗真菌药物发现的有希望的靶点。该研究的中心假设是蛋白质乙酰化在控制白色念珠菌的细胞生理学和毒力方面发挥着关键作用。我们根据初步数据制定了这一假设，表明赖氨酸乙酰化是白色念珠菌中 PTM 的丰富形式。此外，我们之前的工作表明白色念珠菌 Hat1（一种典型的组蛋白赖氨酸乙酰化酶）参与 DNA 损伤修复、形态发生、生物膜形成、抗真菌药物耐药性和毒力。然而，其他几种赖氨酸乙酰转移酶在该生物体中的作用仍然未知。我们的初步研究还表明 Lig4 的两个特定赖氨酸残基（K654 和 K655）发生乙酰化，Lig4 是一种重要的蛋白质，参与非同源末端连接 (NHEJ) 依赖性 DNA 修复并调节白色念珠菌的形态发生和毒力。此外，新的初步 RNA-seq 数据表明 Hat1 在线粒体功能以及非编码 RNA (ncRNA) 的加工和调节中具有重要作用。因此，我们联合申请的主要目标是鉴定和表征白色念珠菌 Hat1 的组蛋白和非组蛋白靶基因，并研究其在线粒体功能调节中的不明确作用以及在 NHEJ DNA 修复中的可能作用。在初步数据的指导下，我们期望通过追求以下三个具体目标来检验我们的中心假设并实现本申请的目标：1) 识别和表征 Hat1 的组蛋白和非组蛋白（非染色质）靶标。 2) 探讨NHEJ DNA修复途径乙酰化在调节白色念珠菌毒力中的可能作用。 3) 研究Hat1在ncRNA加工中的作用。该提案的回报预计将是巨大的，因为我们期望发现对白色念珠菌发病机制重要的关键细胞过程的新调节模式。