Comparative transcriptome analysis reveals distinct gene expression profiles in Brachypodium distachyon infected by two fungal pathogens

Gengrui Zhu,Qinhu Wang,Huiquan Liu,Jin-Rong Xu,Chengyu Gao,Chenyu Wu,Mu Li

doi:10.1186/s12870-021-03019-0

Abstract

BackgroundThe production of cereal crops is frequently affected by diseases caused by Fusarium graminearum and Magnaporthe oryzae, two devastating fungal pathogens. To improve crop resistance, many studies have focused on understanding the mechanisms of host defense against these two fungi individually. However, our knowledge of the common and different host defenses against these pathogens is very limited.ResultsIn this study, we employed Brachypodium distachyon as a model for cereal crops and performed comparative transcriptomics to study the dynamics of host gene expression at different infection stages. We found that infection with either F. graminearum or M. oryzae triggered massive transcriptomic reprogramming in the diseased tissues. Numerous defense-related genes were induced with dynamic changes during the time course of infection, including genes that function in pattern detection, MAPK cascade, phytohormone signaling, transcription, protein degradation, and secondary metabolism. In particular, the expression of jasmonic acid signaling genes and proteasome component genes were likely specifically inhibited or manipulated upon infection by F. graminearum.ConclusionsOur analysis showed that, although the affected host pathways are similar, their expression programs and regulations are distinct during infection by F. graminearum and M. oryzae. The results provide valuable insight into the interactions between B. distachyon and two important cereal pathogens.

Highlights

The production of cereal crops is frequently affected by diseases caused by Fusarium graminearum and Magnaporthe oryzae, two devastating fungal pathogens
Many similar defense responses have been observed in B. distachyon challenged by F. graminearum or M. oryzae, the expression programs and some specific defense responses are very different in these two pathosystems
Distinct global gene expression of Brachypodium infected by two cereal fungi To investigate the transcriptional dynamics during Brachypodium-fungal interactions, we performed RNA-seq analysis on B. distachyon infected by two cereal pathogens: F. graminearum and M. oryzae

Summary

Introduction

The production of cereal crops is frequently affected by diseases caused by Fusarium graminearum and Magnaporthe oryzae, two devastating fungal pathogens. A majority of wheat cultivars are susceptible to F. graminearum infection, the gene expression profiles in the cold-killed and living wheat heads are obviously distinct and suggest that the host defense responses actively suppress fungal growth during infection [18]. In line with this evidence, many transcriptomic studies showed that genes related to oxidative burst, MAPK signaling, hormone biosynthesis, transcription, secondary metabolism, and other defense associated proteins were altered upon infection [19,20,21,22,23,24,25]. These defense responses are observed in M. oryzae infection [26,27,28,29,30,31,32] and many other plant-pathogen interactions [33]

Methods

Results

Conclusion