Transcriptome profiling of the rice blast fungus during invasive plant infection and in vitro stresses

ABSTRACT: Rice blast is the most threatening disease to cultivated rice worldwide. Magnaporthe oryzae, its causal agent is likely to encounter environmental challenges during invasive growth in the host plants that require shifts in gene expression to establish a compatible interaction. Here, we tested the hypothesis that M. oryzae have similar gene expression patterns in planta, versus during in vitro stresses. Gene expression data was collected from in vitro experiments of heat shock, oxidative burst, and three different types of nutrient starvation. These data were compared to fungal gene expression during the invasive growth phase in compatible interactions on two grass hosts, rice and barley. We have identified 4,973 differentially expressed genes, from which 1,909 genes showed similar regulation patterns between at least one of the in vitro stresses and rice and/or barley. Hierarchical clustering of these 1,909 genes showed three major clusters in which growth in planta conditions closely grouped with the starving nutrient conditions. Out of these 1,909 genes, 55 and 129 genes were induced and repressed in all seven treatments, respectively. The functional categorization of those 55 induced genes revealed that most of them are either related to carbon metabolism, membrane proteins, or are involved in oxidoreduction reactions. The 129 repressed genes are putatively involved in vesicle trafficking, signal transduction, nitrogen metabolism, or molecular transport. These findings indicated that M. oryzae is likely coping with nutrient deprived environments in its hosts during the invasive growth stage about 72 hours post-inoculation, and not as much with host defense responses, or a temperature stress. Eight M. oryzae treatments: mycelia grown in liquid complete medium (set as the control); 72 hours post-incoulation (hpi) in rice leaves; 72 hours post-incoulation in barley leaves; mycelia under heat shock; mycelia under oxidative stress; mycelia under minimal medium; mycelia under nitrogen starvation; mycelia under carbon starvation. Three biological replicates had their total RNA pulled after RNA extraction. Dye-swaps used as technical replicates.

ORGANISM(S): Magnaporthe oryzae

SUBMITTER: Nicole Donofrio 

PROVIDER: E-GEOD-21908 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress