Spatial and temporal transcriptional response to drought by Suillus pungens and Pinus muricata

In this study, we used RNA sequencing to measure transcriptional changes in the fungus Suillus pungens (SP) exposed to experimental drought. We grew SP in symbiosis with Pinus muricata (PM) in a growth chamber where we manipulated both long-term (chronic) and short-term (acute) soil moisture and sequenced mRNA extracted from both ectomycorrhizal roots and extraradical mycelium (ERM). Our primary aims were to: (i) demonstrate the utility of RNA sequencing to quantify response to global change stressors for EMF, (ii) identify biological functions involved in drought response by comparing gene expression across moisture treatments and in different parts of EMF, and (iii) estimate the potential for fungal acclimation by comparing gene expression between chronic and acute drought stress treatments.