Multi-layered characterization of the barley interactome links MLA immune receptor signaling with defense gene expression

Authors: VELASQUEZ-ZAPATA, VALERIA - Iowa State University; ELMORE, MITCH - Iowa State University; Fuerst, Gregory; Wise, Roger

Submitted to: International Congress on Molecular Plant-Microbe Interactions
Publication Type: Proceedings
Publication Acceptance Date: 6/22/2021
Publication Date: 12/8/2021
Citation: Velasquez-Zapata, V., Elmore, M.J., Fuerst, G.S., Wise, R.P. 2021. Multi-layered characterization of the barley interactome links MLA immune receptor signaling with defense gene expression. International Congress on Molecular Plant-Microbe Interactions. 34. https://doi.org/10.1094/MPMI-34-9-S2.1.
DOI: https://doi.org/10.1094/MPMI-34-9-S2.1

Interpretive Summary:

Technical Abstract: Obligate fungal pathogens (e.g., mildews and rusts) are a major threat to cereal grain production worldwide. Because they are unable to survive autonomously, obligate parasites are ideal tools to explore interdependent signaling between disease agents and their hosts. The barley MLA immune receptor and its orthologs confer recognition specificitiy to many important cereal diseases, including powdery mildew, stem and stripe rust, Victoria blight, and rice blast. To characterize the regulatory networks required for NLR-based immunity, we used orthologous protein interactome, transcriptome and eQTL data to assemble the cellular and transcriptional cascades of MLA-triggered signaling. Integration of interactome and eQTL data enabled us to infer disease modules associated with powdery mildew penetration and haustorial development, revealing both core and unique responses. Using RNA-Seq data from an infection time-course, we constructed a resistant interactome, representing higher protein essentiality and centrality, and lower co-expression values than the susceptible subnetwork. Fourteen novel protein interactors of MLA were identified, demonstrated to be conserved across orthologs, and positioned in the MLA-associated subnetwork, predicting immune receptor localization, and signaling response over time. Our findings highlight master components of the NLR signaling cascade, linking genomic, transcriptomic, and physical interactions during the MLA-based immune response.