Signaling events during Arbuscular Mycorrhiza symbiosis
L. MUELLER (1), L. Mainzer (2), M. Hudson (2), M. Harrison (3) (1) Boyce Thompson Institute, U.S.A.; (2) Department of Crop Science, University of Illinois, U.S.A.; (3) Boyce Thompson Institute, U.S.A.

Most land plants establish beneficial associations with fungi of the phylum Glomeromycota in order to maximize nutrient uptake from the soil. In arbuscular mycorrhiza symbiosis (AMS), fungal hyphae form arbuscules inside the root cortical cells of the host plant to ensure efficient nutrient exchange. Thus, successful establishment of AMS requires extensive cell-cell communication between the plant and the fungus, but also between different cells of the plant. In order to shed light on novel signaling components we are analyzing a set of candidate genes in the grass Brachypodium distachyon. The candidates were selected based on a RNAseq analysis in B. distachyon AMS roots compared to mock-inoculated controls, which allowed us to identify 3350 significantly differentially regulated genes. Out of these, we selected i), a set of transcription factors, ii), receptor kinases, and iii), small signaling peptides and propose to dissect their molecular function using reverse genetics (T-DNA and CRISPR-Cas9 mutants, as well as overexpression). In addition, Medicago truncatula orthologs of selected candidate genes are being analyzed for AMS phenotypes, as mutant and overexpression analyses are facilitated in the well-established transient root transformation system. Improving our knowledge of molecular mechanisms leading to successful arbuscule formation and symbiosis will potentially enable future optimization of nutrient uptake in crop species for sustainable food-production and to reduce application of fertilizer- use in modern-day agriculture.

Abstract Number: P2-40
Session Type: Poster