Sirtuins and Metabolic Pathway Integration

描述（由申请人提供）：翻译后修饰是细胞适应其环境变化的一种快速有效的方式。生物学家们对推进我们对化学修饰发挥作用的机制的理解很感兴趣，并希望更多地了解这些修饰对细胞复杂代谢网络动态的影响。GM 62203支持的这项工作的长期目标是了解沉默调节蛋白依赖性蛋白酰化/脱酰化系统（SDPADS）对原核细胞生理学的贡献。先前NIH对该项目的资助使我们能够推进我们对SDPADS在革兰氏阴性和革兰氏阳性细菌中的作用的理解。我们现在处于一个很好的位置来进行SDPADS的乙酰转移酶的结构-功能分析，剖析编码SDPADS功能的基因的表达调控，鉴定以前未知的基因的功能，这些基因也参与蛋白质活性的乙酰化控制，建立N-Lys蛋白乙酰化/脱乙酰化在控制中枢代谢途径中的作用，并确定原核生物是否使用SDPADS通过调节转录调节因子的活性来直接控制基因表达。我们将采取多学科的方法来回答原核细胞生理学的基本问题。该提案的前两个目标集中于新发现的乙酰化对代谢和基因表达的影响，后两个目标集中于SDPADS酶的生化和结构表征以及编码SDPADS功能的基因的表达调控。鉴于SDPADS的普遍存在，这一研究领域的进展将对我们理解所有细胞的生理学产生广泛的影响。快速控制蛋白质的生物活性对于细胞在不断变化的环境中的生存至关重要。赖氨酸残基的翻译后修饰对基因表达和代谢具有深远的影响。拟议的工作将推进我们对修饰/去修饰酶功能机制的理解，这些酶构成了所有生命形式中保守的系统。编码修饰/去修饰酶的基因表达的调节是所提出的研究的一部分。在这个项目中，我们试图验证推定的新的蛋白质底物的系统，包括DNA结合调节蛋白。

DESCRIPTION (provided by applicant): Posttranslational modification is a rapid and efficient way in which cells adapt to changes in their environment. Biologists at large are interested in advancing our understanding of the mechanisms through which chemical modifications exert their effects, and want to learn more about the impact that these modifications have on the dynamics of the complex metabolic network of the cell. The long-term goal of the work supported by GM62203 is to understand the contributions of the sirtuin- dependent protein acylation/deacylation system (SDPADS) to prokaryotic cell physiology. Previous NIH funding of this project allowed us to advance our understanding of the role of the SDPADS in Gram- negative and Gram-positive bacteria. We are now in an excellent position to perform structure-function analyses of the acetyltransferase of the SDPADS, to dissect the regulation of expression of the genes encoding SDPADS functions, to identify the function of previously unknown genes also involved in acetylation control of protein activity, to establish a role for N-Lys protein acetylation/deacetylation in the control of central metabolic pathways, and to determine if prokaryotes use the SDPADS to directly control gene expression by modulating the activity of transcription regulators. We will take a multidisciplinary approach to answer fundamental questions of prokaryotic cell physiology. The first two aims of this proposal focus on newly discovered effects of acetylation on metabolism and gene expression, and the last two aims focus on the biochemical and structural characterization of the SDPADS enzymes and on the regulation of expression of the genes encoding SDPADS functions. Given the ubiquity of the SDPADS, advances in this research area will have broad impact on our understanding of the physiology of all cells. PUBLIC HEALTH RELEVANCE Rapid control of biological activities of proteins is critical for the survival of cells in a changing environment. Posttranslational modifications of lysine residues have a profound effect on gene expression and metabolism. The proposed work will advance our understanding of the mechanism of function of the modifying/demodifying enzymes that comprise a system conserved in all forms of life. Regulation of expression of the genes encoding the modifying/demodifying enzymes is part of the proposed studies. In this project we seek to validate putative new protein substrates of the system, including DNA-binding regulatory proteins.