The B Vitamin/Cofactor Network: Command and Control of Metabolism in Changing Conditions

主要研究者：Andrew Hanson（佛罗里达大学盖恩斯维尔分校）合作PI：Christopher亨利（芝加哥大学），Donald McCarty和Jesse Gregory（佛罗里达大学盖恩斯维尔分校）主要合作者：Alisdair费尔尼（马克斯普朗克研究所，戈尔姆，德国）和Svetlana Gerdes（阿贡国家实验室）植物和人类一样需要B，但与人类不同的是，植物自己制造维生素。然而，已经假设植物在暴露于热、干旱或其他气候胁迫时不能产生它们所需的所有B族维生素，并且由此产生的维生素缺乏引起代谢缺陷，导致产量和活力损失。利用玉米，该项目将利用尖端的遗传，基因组和代谢计算机建模方法来测试这一假设，即确定气候压力对代谢的影响程度是由于B族维生素缺乏。潜在的成果包括提供一个新的范例，了解压力代谢和育种适应气候压力，并确定特定的基因，以提高压力适应。关于外联和培训，该项目将提供研究培训活动，使研究人员掌握基因组规模的代谢建模。 除了博士后助理和学生的培训外，该项目还将举办代谢建模和比较基因组学年度研讨会，以培训教师，博士后和学生，重点是来自少数民族服务机构的学生。 B类维生素形成网络。过去的研究表明，这一网络受到气候压力的严重影响，由此产生的维生素缺乏导致植物表现不佳。然而，压力导致B族维生素缺乏的惊人想法从未经过严格的测试。植物中B族维生素缺乏的代谢后果也没有系统的定义。本项目将以玉米为模型，使用代谢系统方法来实现这两个目标。它还将通过识别“缺失”的转运蛋白和酶来填补B族维生素网络中的关键空白。 项目目标是建立一组缺乏维生素B的玉米品系，并获取转录组和代谢组数据;建立代谢模型，首次在植物中将所有B族维生素/辅因子作为工作部分，并利用这些模型预测维生素缺乏如何影响叶片代谢和基因表达;通过比较气候压力和维生素缺乏的转录组和代谢组来预测压力引起的维生素缺乏，并通过提供维生素来验证预测;并且，从转录组数据和建模中识别候选转运蛋白和酶基因，在生物化学和遗传学上验证它们，并通过添加它们来升级模型。这项研究将为B族维生素缺乏如何影响植物基因表达和代谢提供信息，并在此过程中为胁迫代谢的操纵和代谢适应气候胁迫的育种提供新的见解。 所有基因组规模的数据集都将在PlantSEED（http：//plantseed.theseed.org/）和GEO（www.ncbi.nlm.nih.gov/geo/）上公开提供。 该项目的注释、代谢重建和建模功能也将在PlantSEED中公开提供，并将用于支持Gramene、iPlant Collaborative以及AraCyc、MaizeCyc和PlantCyc数据库。缺乏维生素的玉米品系将是研究B族维生素及其与微生物组交换的独特资源，并将通过玉米遗传合作库存中心公开提供。

PI: Andrew Hanson (University of Florida-Gainesville)Co-PIs: Christopher Henry (University of Chicago), Donald McCarty and Jesse Gregory (University of Florida-Gainesville)Key Collaborators: Alisdair Fernie (Max Planck Institute, Golm, Germany) and Svetlana Gerdes (Argonne National Laboratory)Plants need B vitamins just as much as humans do but, unlike humans, plants make their own vitamins. However, it has been hypothesized that plants can fail to make all the B vitamins they need when exposed to heat, drought, or other climatic stresses, and that the resulting vitamin deficiencies cause metabolic defects leading to yield and vigor losses. Using maize, this project will exploit cutting-edge genetic, genomic, and metabolic computer modeling approaches to test this hypothesis, i.e. to determine the extent to which climatic stress effects on metabolism are due to B vitamin deficiency. Potential outcomes include the provision of a new paradigm for understanding stress metabolism and breeding for adaptation to climate stress, and the identification of specific genes to improve stress adaptation. With regard to outreach and training, the project will provide for research training activities that will put genome-scale metabolic modeling in researchers' hands. In addition to the training of postdoctoral associates and students, the project will hold a yearly workshop in metabolic modeling and comparative genomics to train faculty, postdoctorals, and students with an emphasis on those from Minority-serving Institutions. B Vitamins form a network. Past studies imply that this network is severely impacted by climatic stresses and that the resulting vitamin deficiencies lead to plant underperformance. However the surprising idea that stresses cause B vitamin deficiencies has never been rigorously tested. Nor have the metabolic consequences of B vitamin depletion in plants been systematically defined. This project will do both using a metabolic systems approach with maize as a model. It will also fill crucial gaps in the B vitamin network by identifying 'missing' transporters and enzymes. Project objectives are to create a panel of vitamin B-deficient maize lines and acquire transcriptome and metabolome data; build metabolic models that - for the first time in plants - will include all B vitamins/cofactors as working parts and use them to predict how vitamin deficiency affects leaf metabolism and gene expression; predict stress-induced vitamin deficiency by comparing climate-stress and vitamin-deficiency transcriptomes and metabolomes, and validate predictions by supplying vitamins; and, identify candidate transporter and enzyme genes from transcriptome data and modeling, validate them biochemically and genetically, and upgrade the model by adding them. This research will inform perspectives on how B vitamin deficiency impacts plant gene expression and metabolism and in so doing, provide new insight into the manipulation of stress metabolism and breeding for metabolic adaptation to climate stress. All genome-scale datasets will be publicly available at PlantSEED (http://plantseed.theseed.org/) and GEO (www.ncbi.nlm.nih.gov/geo/). The project's annotation, metabolic reconstruction, and modeling capabilities will also be publicly available in PlantSEED and will be leveraged to support Gramene, the iPlant Collaborative, and the AraCyc, MaizeCyc, and PlantCyc databases. Vitamin-deficient maize lines will be a unique resource to study B vitamins and their exchange with the microbiome, and will be made publicly available via the Maize Genetics Cooperation Stock Center.