The bZIP transcription factor BIP1 of the rice blast fungus is essential for infection and regulates a specific set of appressorium genes

作者：Karine Lambou, Andrew G. Tag, Alexandre Lassagne, Jérôme Collemare, Pierre-Henri Clergeot, Crystel Barbisan, Philippe Perret, Didier Tharreau, Joelle Millazo, Elia Chartier, Ronald P. de Vries, Judith Hirsch, Jean‐Benoit Morel, Roland Beffa, Thomas Kroj, Terry L. Thomas, Marc‐Henri Lebrun · 发表于：PLoS Pathogens · 年份：2024 · DOI：10.1371/journal.ppat.1011945 · 被引用次数：9 · 研究领域：Fungal and yeast genetics research、Plant-Microbe Interactions and Immunity、Plant Disease Resistance and Genetics

The rice blast fungus Magnaporthe oryzae differentiates specialized cells called appressoria that are required for fungal penetration into host leaves. In this study, we identified the novel basic leucine zipper (bZIP) transcription factor BIP1 (B-ZIP Involved in Pathogenesis-1) that is essential for pathogenicity. BIP1 is required for the infection of plant leaves, even if they are wounded, but not for appressorium-mediated penetration of artificial cellophane membranes. This phenotype suggests that BIP1 is not implicated in the differentiation of the penetration peg but is necessary for the initial establishment of the fungus within plant cells. BIP1 expression was restricted to the appressorium by both transcriptional and post-transcriptional control. Genome-wide transcriptome analysis showed that 40 genes were down regulated in a BIP1 deletion mutant. Most of these genes were specifically expressed in the appressorium. They encode proteins with pathogenesis-related functions such as enzymes involved in secondary metabolism including those encoded by the ACE1 gene cluster, small secreted proteins such as SLP2, BAS2, BAS3, and AVR-Pi9 effectors, as well as plant cuticle and cell wall degrading enzymes. Interestingly, this BIP1 network is different from other known infection-related regulatory networks, highlighting the complexity of gene expression control during plant-fungal interactions. Promoters of BIP1-regulated genes shared a GCN4/bZIP-binding DNA motif (TGACTC) bindi...