Comparative transcriptome profiling identifies maize line specificity of fungal effectors in the maize–Ustilago maydis interaction

  • The biotrophic pathogen Ustilago maydis causes smut disease on maize (Zea mays) and induces the formation of tumours on all aerial parts of the plant. Unlike in other biotrophic interactions, no gene-for-gene interactions have been identified in the maize–U. maydis pathosystem. Thus, maize resistance to U. maydis is considered a polygenic, quantitative trait. Here, we study the molecular mechanisms of quantitative disease resistance (QDR) in maize, and how U. maydis interferes with its components. Based on quantitative scoring of disease symptoms in 26 maize lines, we performed an RNA sequencing (RNA-Seq) analysis of six U. maydis-infected maize lines of highly distinct resistance levels. The different maize lines showed specific responses of diverse cellular processes to U. maydis infection. For U. maydis, our analysis identified 406 genes being differentially expressed between maize lines, of which 102 encode predicted effector proteins. Based on this analysis, we generated U. maydis CRISPR/Cas9 knock-out mutants for selected candidate effector sets. After infections of different maize lines with the fungal mutants, RNA-Seq analysis identified effectors with quantitative, maize line-specific virulence functions, and revealed auxin-related processes as a possible target for one of them. Thus, we show that both transcriptional activity and virulence function of fungal effector genes are modified according to the infected maize line, providing insights into the molecular mechanisms underlying QDR in the maize–U. maydis interaction.
Author:Selma Schurack, Jasper R. L. Depotter, Deepak Gupta, Marco ThinesORCiDGND, Gunther DöhlemannORCiDGND
Parent Title (English):The plant journal
Place of publication:Oxford [u.a.]
Document Type:Article
Date of Publication (online):2021/02/11
Date of first Publication:2021/02/11
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2021/09/08
Tag:CRISPR-Cas9; Ustilago maydis; Zea mays; effectors; quantitative disease resistance; transcriptome analysis
Page Number:20
First Page:733
Last Page:752
This work was funded by the European Research Council under the European Union’s Horizon 2020 research and innovation programme (consolidator grant conVIRgens, ID 771035), as well as funding by the Deutsche Forschungsgemeinschaft (German Research Foundation [DFG]) under Germany’s Excellence Strategy (EXC-2048/1 – Project ID: 390686111). Jasper Depotter is supported by the Research Fellowship Programme for Postdoctoral Researchers of the Alexander von Humboldt Foundation. Marco Thines and Deepak K. Gupta are supported by the LOEWE initiative of the government of Hesse, in the framework of the centre for Translational Biodiversity Genomics (TBG). Open Access funding enabled and organized by Projekt DEAL.
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie
5 Naturwissenschaften und Mathematik / 58 Pflanzen (Botanik) / 580 Pflanzen (Botanik)
Licence (German):License LogoCreative Commons - Namensnennung-Nicht kommerziell - Keine Bearbeitung 4.0