NSF Postdoctoral Fellowship in Biology FY 2021: Spatially Resolving the Cellular Landscape of Arbuscular Mycorrhizal Symbiosis with M. truncatula and D. epigaea

该行动为2021财年的NSF植物基因组博士后生物学研究奖学金提供资金。该研究金支持研究员在东道实验室的研究和培训计划，研究员还提出了扩大生物学参与的计划。该奖学金的研究和培训计划的标题为特雷弗蒂维是“使用空间RNA-Seq和内循环分析空间解析丛枝菌根共生与蒺藜苜蓿和Diversispora epigaea的细胞景观”。该奖学金的主办机构是博伊斯汤普森研究所，赞助科学家是玛丽亚哈里森博士。广泛多样的植物和有限的土壤真菌群体在一种称为丛枝菌根共生的协会中相互作用。植物和真菌之间的这种地下关系发生在植物根细胞内，并帮助植物和真菌获得关键的营养物质。控制这种共生关系的关键植物基因已经被确定，但是在定殖过程中植物和真菌基因表达的时间和调控是复杂的，需要进一步的理解。为了表征这种相互作用，该项目将在共生过程中以精细的空间分辨率测量植物和真菌的转录本，并确定真菌定植梯度沿着细胞之间的基因表达差异。该项目的结果将有助于开发用于研究根-微生物相互作用的资源，并使这些方法能够应用于解决主要作物中的类似问题。在此过程中，该项目将促进生物学专业本科生的参与研究，并通过外展和教学支持当地社区的学生。该项目将使用空间mRNA-Seq绘制植物和真菌转录组，并沿着沿着时空梯度的定殖比较所有植物细胞类型中的基因表达，从而创建植物-真菌基因共表达网络，并将转录组学和显微镜下的内倍性证据相关联以鉴定候选基因途径。为了解决对核内倍性的控制，植物突变体，细胞周期标记和图像分析将被用来破坏共生信号传导，并检查对核内复制的影响。对AM共生中内倍性的重要性的进一步了解有可能为植物中共生和寄生生物营养型定殖机制提供信息。空间转录组数据集将在NCBI基因表达综合数据库中公开提供。M. truncatula细胞周期标记线和内循环调控突变体将共享未来的实验研究的植物细胞周期和biotrophic interactions.Keywords：host-microbial，mycorrhiza，spatial transcriptomics，endoreduplication，colonizationThis award reflects NSF's法定使命，并已被认为是值得的支持，通过评估使用基金会的智力价值和更广泛的影响审查标准。

This action funds an NSF Plant Genome Postdoctoral Research Fellowship in Biology for FY 2021. The fellowship supports a research and training plan in a host laboratory for the Fellow who also presents a plan to broaden participation in biology. The title of the research and training plan for this fellowship to Trevor Tivey is "Using Spatial RNA-Seq and endocycle analyses to spatially resolve the cellular landscape of arbuscular mycorrhizal symbiosis with Medicago truncatula and Diversispora epigaea". The host institution for the fellowship is the Boyce Thompson Institute and the sponsoring scientist is Dr. Maria Harrison.A broad diversity of plants and a limited group of soil fungi interact together in a type of association known as arbuscular mycorrhizal symbiosis. This underground relationship between plants and fungi takes place within plant root cells, and helps both plants and fungi acquire critical nutrients. Key plant genes governing this symbiosis have been identified, however the timing and regulation of plant and fungal gene expression during colonization is complex and requires further understanding. To characterize this interaction, this project will measure plant and fungal transcripts during symbiosis at a fine spatial resolution and identify gene expression differences between cells along a gradient of fungal colonization. Results from this project will help to develop resources for the study of root-microbe interactions and enable the application of these methods to address similar questions in major crops. In the process, this project will promote research participation of undergraduates who are underrepresented in biology and support students from the local community through outreach and teaching.This project will use spatial mRNA-Seq to map the plant and fungal transcriptomes and compare gene expression in all plant cell types along a spatiotemporal gradient of colonization, enable the creation of plant-fungal gene co-expression networks, and correlate transcriptomic and microscopical evidence of endoploidy to identify candidate gene pathways. To address the controls on endoploidy, plant mutants, cell cycle markers, and image analysis will be used to disrupt symbiosis signaling and to examine the effects on endoreduplication. An increased understanding of the significance of endoploidy in AM symbiosis has the potential to inform mechanisms of symbiotic and parasitic biotroph colonization in plants. Spatial transcriptome datasets will be made publicly available in the NCBI Gene Expression Omnibus. M. truncatula cell cycle marker lines and endocycle regulation mutants will be shared for future experimental studies of the plant cell cycle and biotrophic interactions.Keywords: host-microbe, mycorrhiza, spatial transcriptomics, endoreduplication, colonizationThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.