TRR 356 Project: Microbiota-Assisted Pathogenicity in the Arabidopsis Phyllosphere
This project, within the TRR 356 PlantMicrobe framework, investigates how microbial interactions influence the pathogenicity of the white rust pathogen Albugo laibachii on Arabidopsis thaliana leaves. Specifically, we focus on the basidiomycete yeast Dioszegia hungarica and its role in facilitating pathogen colonization through nutrient exchange. Our goal is to uncover mechanisms by which non-pathogenic yeasts enhance A. laibachii infection efficiency, shedding light on microbial dependencies and potential strategies for biocontrol.
Project Goals
The TRR 356 project is centered on three main objectives:
- Identify Key Microbial Interactions that Promote Pathogen Colonization
Discover interactions among leaf-associated microbes that enable Albugo to overcome nutrient limitations and establish infection. - Characterize Genetic Mechanisms in Dioszegia that Assist Pathogen Growth
Analyze genetic traits in Dioszegia hungarica that influence its ability to support A. laibachii, focusing on nutrient cross-feeding pathways. - Develop Predictive Models for Microbiota-Driven Pathogenicity
Use findings from microbial interactions to predict microbiota configurations that influence plant health and pathogen resistance.
Research Focus
1. Microbial Interactions that Promote Pathogenicity
This area explores how specific microbes support pathogen colonization by providing essential nutrients or environmental stability.
- Recent Findings: We identified Dioszegia hungarica as a crucial partner that enhances Albugo laibachii colonization. Our research revealed that Dioszegia synthesizes a vitamin essential for Albugo but not synthesized by the pathogen itself. This cross-feeding enables A. laibachii to establish a stable infection on Arabidopsis, highlighting the role of microbial partnerships in pathogen success (Hu et al. in preparation).
2. Genetic Mechanisms of Cross-Feeding
This work package focuses on identifying genes in Dioszegia that facilitate nutrient provision to A. laibachii.
- Recent Findings: Through genome and transcriptome analyses, we identified a permease in Dioszegia, which is highly expressed in strains that promote A. laibachii infection. This permease allows efficient vitamin transfer, illustrating a molecular mechanism for nutrient exchange that directly supports Albugo colonization. The presence of this gene in Dioszegia suggests co-evolutionary adaptation with A. laibachii in the phyllosphere environment (Hu et al. in preparation).
3. Modeling Microbiota-Assisted Pathogenicity
Our goal is to develop models to predict plant susceptibility based on microbiota composition, focusing on interactions that promote pathogen colonization.
- Recent Findings: By mapping interactions in the Arabidopsis phyllosphere, we are identifying microbial networks that influence pathogen success. This includes the selective influence of Dioszegia strains on Albugo infection efficiency, providing a framework to model and eventually manipulate phyllosphere communities to control plant pathogens.
Innovative Approach
This project combines genomic, microbiome, and functional analyses to explore complex host-microbe and microbe-microbe interactions. By focusing on cross-feeding and co-evolutionary traits, we aim to deepen understanding of microbiota-assisted pathogenicity and open new possibilities for biocontrol by manipulating plant-associated microbiota.
Significance and Future Impact
The findings of this project reveal how non-pathogenic microbes can facilitate pathogen success by providing essential nutrients. This research advances our understanding of the microbial interactions that support or hinder plant health, with potential applications in developing microbiome-based approaches to disease management.