Comparative proteomics analysis of young spikes of wheat in response to Fusarium graminearum infection

Abstract

To investigate signaling events and defense responses in wheat–Fusarium graminearum interaction, the proteomes of young spikes with and without 24 h of F. graminearum inoculation were investigated in the resistant wheat variety Sumai 3 and the susceptible Huaimai 27. Totally 96 protein spots displayed differential expressions in one or two materials after inoculation. 65 of them were identified through mass spectrometry analysis. These proteins can be functionally classified into 12 categories and most of them participate in defense response and signaling. Our study revealed an accumulation of defense/stress response proteins, suppression of protein synthesis and photosynthesis, and changes in basal and energy metabolisms during compatible and incompatible interactions. However, differential regulation of hormone signaling, proteasome-mediated proteolysis, nitrogen metabolism, transcription, and protein modification was observed between two interactions. This result was further confirmed by analyzing the corresponding genes of 19 important proteins from six functional groups at the mRNA level. In addition, the resistant and susceptible wheat varieties showed differences in antioxidant enzymes activities and malondialdehyde contents 24-h postinoculation. Overall, the current study allows us to further dissect the possible metabolism and regulation progresses activated in F. graminearum-treated wheat spikes, and offers new understanding of mechanisms underlying wheat scab resistance.