Small Molecule Signaling in Caenorhabditis elegans

描述（由申请人提供）：秀丽隐杆线虫是生物医学研究中最重要的模式生物之一，因为它具有生物学上的可塑性，而且它的许多生理途径与人类的相应途径有很强的相似性。该项目的目标是通过对秀丽隐杆线虫代谢组的全面结构和功能表征来补充高度发达的基因组学和蛋白质组学，令人惊讶的是，这方面的探索程度非常有限。这项工作的动机是几条线索的证据表明，结构很大程度上不确定的小分子在秀丽隐杆线虫的内分泌和外分泌信号中发挥重要作用，特别是在调节寿命、发育和代谢的关键途径中。该研究的核心是使用新的核磁共振光谱方法，该方法允许分析复杂的小分子混合物，并大大加快了结构解析过程和检测化合物的功能表征。该方法允许比较来自不同秀丽隐杆线虫突变菌株的复杂代谢物样本，并确定由于特定突变而生物合成强烈上调或下调的化合物的化学结构。在这个项目中，选择了少数突变株，其表型表明影响寿命，发育或脂肪代谢的小分子信号缺陷。核磁共振光谱学将用于检测和鉴定与这些表型相关的化合物。随后，鉴定化合物的合成样品将进行化学遗传筛选，以确定对寿命，发育调节和脂肪代谢调节的影响。在野生型秀丽隐杆线虫中显示活性的化合物将接受突变株或RNAi菌株的额外测试，这些菌株代表了与衰老和发育相关的关键遗传途径。该项目的成功完成将为秀丽隐杆线虫代谢组提供部分结构和功能注释，大大增加我们对秀丽隐杆线虫生物学基本途径和哺乳动物相应疾病相关途径的理解。所产生的小分子知识不仅将使未来的努力瞄准更多样化的化学遗传筛选，探索秀丽隐杆线虫的生物学和生态学的其他方面，而且还将用于与农业或医学相关的线虫物种。此外，用于表征秀丽隐杆线虫信号分子的方法将促进对其他模式生物小分子代谢物结构和功能表征的类似研究。

DESCRIPTION (provided by applicant): The nematode Caenorhabditis elegans is one of the most important model organisms for biomedical research, because of its biological tractability and because many of its physiological pathways show strong analogies to corresponding pathways in humans. The goal of this project is to complement the highly developed genomics and proteomics of C. elegans with a comprehensive structural and functional characterization of its metabolome, which, surprisingly, has been explored to only a very limited extent. This effort is motivated by several lines of evidence indicating that small molecules of largely undetermined structure play important roles in C. elegans endocrine and exocrine signaling, specifically in key pathways regulating lifespan, development, and metabolism. Central to the proposed research is the use of new NMR-spectroscopic methodology that permits the analysis of complex small molecule mixtures and greatly accelerates both the structure elucidation process and the functional characterization of the detected compounds. This methodology permits to compare complex metabolite samples derived from different C. elegans mutant strains, and to identify the chemical structures of compounds whose biosynthesis is strongly up- or downregulated as a result of a specific mutation. For this project, a small number of mutant strains were selected whose phenotypes suggest a defect in small-molecule signaling affecting lifespan, development, or fat metabolism. NMR-spectroscopy will be used to detect and identify compounds that correlate with these phenotypes. Subsequently, synthetic samples of the identified compounds will be subjected to chemical genetic screens to determine effects on lifespan, developmental regulation and fat metabolism regulation. Compounds that show activity in wild-type C. elegans will be subjected to additional assays with mutant or RNAi strains representative of key genetic pathways related to ageing and development. Successful conclusion of this project will provide a partial structural and functional annotation of the C. elegans metabolome, substantially increasing our understanding of fundamental pathways in C. elegans biology and corresponding disease-relevant pathways in mammals. The small-molecule knowledge generated will not only enable future efforts aimed at more varied chemical genetic screens exploring additional aspects of the biology and ecology of C. elegans, but also of nematode species relevant in agriculture or medicine. Furthermore, methodology developed for characterizing C. elegans signaling molecules will facilitate similar studies toward structural and functional characterization of small molecule metabolites from other model organisms.