Study of fungi with endophytic and mycoparasitic lifestyles for their multiple effects on host traits

研究具有内生和真菌寄生生活方式的真菌对宿主性状的多重影响

• 批准号: RGPIN-2017-05286
• 负责人: Vujanovic, Vladimir
• 金额: $ 1.75万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=680002
• 关键词: Study; fungi; endophytic; mycoparasitic; lifestyles

With global warming, plants face increasing stress from drought and disease. Understanding how plant mycosymbionts (myks='fungus', sumbiosis='mutualism') improve plant resistance is critical for maintaining plant diversity, and sustainable crop production. Each evolutionary group of plants adapts by harboring mycosymbionts, a consortia of beneficial endophytes and mycoparasites residing within plant tissue. Forming the plant's 'second genome', they are among the main positive contributors to seed resilience and germination, a vital phase to a plant's lifecycle and adaptability. My program has established itself as a leader in this research area, as evidenced by leading the discovery of mycovitality (vitalitas='vital force'), which defines plant performance in a continuum with mycotrophy (trophe='nutrition'). Mycovitality (endophyte-seed association) induces coleorhiza-driven seed stratification and specific expression of phytohormone biosynthesis genes to achieve both improved germination/seedling emergence and stress tolerance in wheat (Triticaceae). The concept has peaked the interest of the global food security industry; however, a number of scientific questions still remain to be answered including, (a) over the course of the plant-fungus co-evolution, how have plants selected distinct, genome-specific profiles of seed endosymbionts? and (b) how does the endophytic inoculant manipulate the plant microbiome, so as to control plant behavioral adaptations and evolutionary pathways? Investigating the plant microbiome as a system demands meta-omics and comparative studies to unravel gray areas of plant-endophyte symbiosis. In this project, a combination of MiSeq next generation sequencing (NGS) technology will be applied to study the metagenomics of endosymbionts. The NGS will then be coupled with qPCR/microarray, confocal microscopy, FTIR spectroscopy and LC/MSMS analytical methods to elucidate plant's microbiome and metabolome responses to abiotic and biotic stresses. Quantifying metabolic shift in the seed tissues of Aegilops-Triticum host genotypes is essential for understanding endophytism's effect on seed germination. Mapping the expression of key functional genes across plant phenotypes will aid in elucidating the mechanisms by which endosymbionts improve host traits, with evolutionary effects on stress tolerance. Moreover, polyploidization events, which define the evolutionary divergence of cereals, will be key in explaining co-evolution. Comparing functional seed tissues of cereals' with those of Arabidopsis' using -omics techniques would identify specific phenotypical changes in the plant's ontogeny related to endosymbiosis. The overall goal is to generate fundamental knowledge on endosymbiosis so as to better understand plant evolutionary traits, thus creating a tool for improved crop stress resilience and productivity.

随着全球变暖，植物面临着越来越大的干旱和疾病压力。了解植物真菌共生体（myks=“真菌”，sumbiosis=“互惠共生”）如何提高植物抗性对于维持植物多样性和可持续作物生产至关重要。植物的每个进化群体都通过容纳真菌共生体来适应，真菌共生体是植物组织内有益内生菌和真菌寄生虫的联合体。它们形成了植物的“第二基因组”，是种子恢复力和发芽的主要积极贡献者之一，种子恢复力和发芽是植物生命周期和适应性的重要阶段。我的项目已成为该研究领域的领导者，这一点可以通过领导发现真菌活力（vitalitas =“生命力”）来证明，它定义了与真菌营养（trope =“营养”）连续体中的植物性能。真菌活力（内生菌-种子关联）诱导鞘根驱动的种子分层和植物激素生物合成基因的特异性表达，以提高小麦（小麦科）的发芽/出苗和胁迫耐受性。这一概念引起了全球食品安全行业的极大兴趣；然而，仍有许多科学问题有待解答，包括：（a）在植物-真菌共同进化的过程中，植物如何选择种子内共生体的独特的、基因组特异性的特征？ (b) 内生接种剂如何操纵植物微生物组，从而控制植物的行为适应和进化途径？研究植物微生物组作为一个系统需要元组学和比较研究来揭示植物与内生菌共生的灰色地带。在该项目中，将结合MiSeq下一代测序（NGS）技术来研究内共生体的宏基因组学。然后，NGS 将与 qPCR/微阵列、共焦显微镜、FTIR 光谱和 LC/MSMS 分析方法相结合，以阐明植物的微生物组和代谢组对非生物和生物胁迫的反应。量化山羊草-小麦宿主基因型种子组织的代谢变化对于了解内生菌对种子萌发的影响至关重要。绘制植物表型关键功能基因的表达图谱将有助于阐明内共生体改善宿主性状的机制，以及对胁迫耐受性的进化影响。此外，定义谷物进化分歧的多倍化事件将是解释共同进化的关键。使用组学技术比较谷物的功能性种子组织与拟南芥的功能性种子组织将识别与内共生相关的植物个体发育的特定表型变化。总体目标是生成有关内共生的基础知识，以便更好地了解植物进化特征，从而创建提高作物逆境恢复能力和生产力的工具。