RT Journal Article SR Electronic T1 The transcriptional landscape of plant infection by the rice blast fungus Magnaporthe oryzae reveals distinct families of temporally co-regulated and structurally conserved effectors JF bioRxiv FD Cold Spring Harbor Laboratory SP 2022.07.18.500532 DO 10.1101/2022.07.18.500532 A1 Yan, Xia A1 Tang, Bozeng A1 Ryder, Lauren S. A1 MacLean, Dan A1 Were, Vincent M. A1 Eseola, Alice Bisola A1 Cruz-Mireles, Neftaly A1 Foster, Andrew J. A1 Osés-Ruiz, Miriam A1 Talbot, Nicholas J. YR 2022 UL http://biorxiv.org/content/early/2022/07/25/2022.07.18.500532.abstract AB The rice blast fungus Magnaporthe oryzae causes a devastating disease which threatens global rice production. In spite of intense study, the biology of plant tissue invasion during blast disease remains poorly understood. Here we report a high resolution, transcriptional profiling study of the entire plant-associated development of the blast fungus. Our analysis revealed major temporal changes in fungal gene expression during plant infection. Pathogen gene expression could be classified into 10 modules of temporally co-expressed genes, providing evidence of induction of pronounced shifts in primary and secondary metabolism, cell signalling and transcriptional regulation. A set of 863 genes encoding secreted proteins are differentially expressed at specific stages of infection, and 546 were predicted to be effectors and named MEP (Magnaporthe effector protein) genes. Computational prediction of structurally-related MEPs, including the MAX effector family, revealed their temporal co-regulation in the same co-expression modules. We functionally characterised 32 MEP genes and demonstrate that Mep effectors are predominantly targeted to the cytoplasm of rice cells via the biotrophic interfacial complex (BIC), and use a common unconventional secretory pathway. Taken together, our study reveals major changes in gene expression associated with blast disease and identifies a diverse repertoire of effectors critical to successful infection.Competing Interest StatementThe authors have declared no competing interest.