A Fusarium pseudograminearum secreted protein, Fp00392, is a major virulence factor during infection and identified as a PAMP

As a main causal agent of wheat crown rot, Fusarium pseudograminearum secrets numerous proteins into the host during the infection process to regulate host immune responses and contribute to the virulence of F. pseudograminearum. In this study, the secreted protein Fp00392 from F. pseudograminearum was found to trigger cell death in Nicotiana benthamiana. Purified Fp00392 protein could activate the ROS burst, callose deposition, and the upregulation of defense-related genes in N. benthamiana. Moreover, the VIGS assay in N. benthamiana showed that Fp00392-triggered cell death is independent of BAK1 and SOBIR1. Furthermore, the transcript level of Fp00392 was significantly induced during F. pseudograminearum infection. Knockout of Fp00392 significantly attenuated the pathogenicity of F. pseudograminearum on wheat coleoptiles. Deletion of Fp00392 affected the sensitivity of F. pseudograminearum to H₂O₂ and Congo Red. Overall, these results indicate that Fp00392 can not only induce plant immune response as a PAMP, but it can also promote F. pseudograminearum infection as a virulence factor.