RUI: Diurnal and circadian regulation of the plant microbiome

植物与土壤微生物在整个生命周期中的特异性相互作用对植物的生长和生存起着重要作用。作为固着生物，植物直接受到环境条件持续但可预测的变化的影响。这包括24小时光/暗周期，植物根据该周期调整其各种生理过程。为了确保成功的相互作用，植物影响某些土壤微生物群体的概况和可能的生物学，使得它们与植物生理过程中的日常变化保持同步。更好地了解这种动态调节将为理解某些土壤微生物与植物根系成功相互作用的机制和过程提供有价值的信息。由于植物与土壤微生物的日常相互作用的总和是它们对植物长期有益的基础，因此在分子水平上理解这些日常相互作用是重要的。通过植物育种对这些日常相互作用的操纵可以通过与某些天然微生物的有效相互作用来提高植物生产力，减少农业操作对昂贵的合成肥料的依赖。该项目还提供了宝贵的机会，让本科生和高中生参与科学研究，并向他们介绍自然和可持续的食品生产方法。 微生物组对宿主的健康和营养状况具有深远的影响。在动物中，光和宿主的生物钟，一种细胞自主的内部生物计时器，在许多代谢和生理过程中产生大约24小时的节律，调节宿主-微生物组的相互作用。本研究的第一个目的是使用宏基因组学方法研究拟南芥的昼夜节律钟在其与细菌微生物组的相互作用中的作用。植物的生物钟将受到环境和遗传的干扰。将通过在DNA和RNA水平上对细菌16 S-核糖体（r）基因进行测序来确定内层和土壤细菌谱的24小时波动，以更好地了解昼夜节律钟调节的作用。第二个目的是确定根和细菌的途径，这种动态的相互作用，使用元转录组学方法。根和细菌的转录组将耗尽核糖体RNA和测序，以确定可能的机制和过程，通过这些机制和过程，一些内分泌细菌与拟南芥根相互作用。第三个目的是研究每天的细菌波动对植物性能的作用，使用生理方法。将通过在正常光/暗循环或延长的恒定光照下生长拟南芥、番茄和大豆植物两代来调节土壤。通过每周测量总叶直径和叶柄长度、植物高度、叶绿素含量和气孔导度来评估拟南芥、番茄和大豆植物在这些调理土壤上的表现。 这项研究的结果将是对植物宿主及其内生微生物之间关系的昼夜节律影响的综合分析。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

The specific interactions of plants with various soil microorganisms throughout their life cycle play important roles in plant growth and survival in nature. Being sessile organisms, plants are directly affected by the continuous but predictable changes in environmental conditions. This includes the 24-hour light/dark cycle according to which plants adjust their various physiological processes. To ensure successful interaction, plants influence the profile and possibly the biology of certain groups of soil microorganisms such that they stay in synchrony with the daily changes in the plant physiological processes. A better understanding of this dynamic regulation would provide valuable information towards understanding the mechanisms and processes through which some soil microbes successfully interact with plant roots. Since the summation of the daily plant interactions with the soil microbes is the basis for their long-term benefits on the plants, understanding these daily interactions at the molecular level is important. The manipulation of these daily interactions through plant breeding may allow for improved plant productivity through efficient interaction with certain natural microbes, reducing the dependency of agricultural operations on expensive synthetic fertilizers. This project also provides valuable opportunities to engage undergraduate and high-school students in scientific research and introduce them to the natural and sustainable approaches of food production. The microbiome has profound effect on a host's health and nutritional status. In animals, light and the host's circadian clock, a cell-autonomous internal biological timekeeper that generates roughly 24-hour rhythms in many metabolic and physiological processes, regulate host-microbiome interactions. The first aim of this research is to study the roles of the Arabidopsis thaliana's circadian clock on its interaction with the bacterial microbiome in the endosphere (inhabiting the root interior) using a metagenomic approach. The plant circadian clock will be disrupted environmentally and genetically. The 24-hour fluctuations in the endospheric and soil bacterial profiles will be determined by sequencing bacterial 16S-ribosomal (r) genes at both the DNA and RNA level to better understand the role of the circadian clock regulation. The second aim is to identify the root and bacterial pathways underlying this dynamic interaction using a metatranscriptomic approach. Both root and bacterial transcriptomes will be depleted of ribosomal RNAs and sequenced to identify possible mechanisms and processes through which some endospheric bacteria interact with Arabidopsis roots. The third aim is to investigate the role of daily bacterial fluctuations on plant performance using a physiological approach. Soils will be conditioned by growing Arabidopsis, tomato, and soybean plants in normal light/dark cycles or prolonged constant light for two generations. The performance of Arabidopsis, tomato, and soybean plants on these conditioned soils will be assessed by weekly measurements of total leaf diameter and petiole length, plant height, chlorophyll content, and stomatal conductance. The outcome from this research will be an integrated analysis of circadian impacts on the relationship between plant hosts and their endophytic microbiomes.This 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.