NSF PRFB FY23: Cross-species gene regulation of a plant-fungal symbiosis under environmental stress

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2023, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment, and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. About 75% of all land plants partner with just one type of fungus, "arbuscular mycorrhizal fungi". This relationship shapes how plants get nutrients and how whole ecosystems function. Whether this relationship is useful for plants depends on environmental factors like nutrient availability. For example, fungi often help plants when nutrients are scarce, but can harm plants when plants can easily get nutrients on their own. Unfortunately, the genes that control when this relationship harms or helps plants are not well-known. Knowing which genes determine when fungi benefit plants will be vital to using fungi in agriculture and biodiversity efforts. The fellow will use large gene surveys, greenhouse experiments, and microscopy to explore how plants and fungi impact each other’s genes under different conditions. The fellow also proposes broadening participation in biology by continuing to mentor students from diverse backgrounds and organizing career development seminars for students. These seminars will provide necessary knowledge for applying to careers in STEM. The fellow will identify genetic regulation occurring across species (i.e., plant genes that regulate fungal genes and vice versa) to understand how plants and fungi co-regulate their relationship in different environmental conditions. The fellow will satisfy this objective in three aims: 1) the fellow will explore how environmental stress reorganizes co-expression patterns of plant and fungal genes using gene co-expression networks, 2) the fellow will use plant growth assays of the model legume Medicago trunculata missing potentially important regulatory genes (i.e., genes with many connections in the above networks) with/without arbuscular mycorrhizal fungi under different stresses, and, lastly, 3) the fellow will grow Medicago truncatula with 19 different characterized fungal isolates to explore how genetic/functional diversity of fungal partners impacts context-dependency of plant-mycorrhizal associations. Through the completion of this project and working closely with Drs. John Stinchcombe and Vasilis Kokkoris, the fellow will: 1) refine his training in next-generation sequencing and multivariate statistics, 2) gain skills in fungal biology and fungal assays, and 3) develop as a mentor through teaching biology courses and developing courses through his professional development seminar series. 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.