A fungal member of the Arabidopsis thaliana phyllosphere antagonizes Albugo laibachii via a GH25 lysozyme
Abstract
Plants are not only challenged by pathogenic organisms, but also colonized by commensal microbes. The network of interactions these microbes establish with their host and amongst each other is suggested to contribute to the immune responses of plants against pathogens. In wild Arabidopsis thaliana populations, the oomycete pathogen Albugo laibachii plays an influential role in structuring the leaf phyllosphere. We show that the epiphytic yeast Moesziomyces bullatus ex Albugo on Arabidopsis, a close relative of pathogenic smut fungi, is an antagonistic member of the A. thaliana phyllosphere, which reduces infection of A. thaliana by A. laibachii. Combination of transcriptomics, reverse genetics and protein characterization identified a GH25 hydrolase with lysozyme activity as a major effector of this microbial antagonism. Our findings broaden the understanding of microbial interactions within the phyllosphere, provide insights into the evolution of epiphytic basidiomycete yeasts and pave the way for novel biocontrol strategies.
Data availability
Genome information and RNA sequencing have been submitted to NCBI Genbank and are available under the following links: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE148670
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (SPP 2125 DECRyPT)
- Katharina Eitzen
- Priyamedha Sengupta
Deutsche Forschungsgemeinschaft (EXC-2048/1,Project ID 390686111)
- Katharina Eitzen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Caroline Gutjahr, Technical University of Munich, Germany
Version history
- Received: November 30, 2020
- Accepted: January 10, 2021
- Accepted Manuscript published: January 11, 2021 (version 1)
- Version of Record published: February 8, 2021 (version 2)
Copyright
© 2021, Eitzen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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