Plant roots employ cell-layer specific programs to respond to pathogenic and beneficial microbes

As plant roots are built of concentric cell-layers, it is anticipated that these respond to microbial infection by employing specific, genetically defined programs. Due to cell-type specific expression of tagged ribosomes, ribosome-bound mRNA was isolated to obtain cell-layer translatomes. After inoculation with the vascular pathogen Verticillium longisporum, the pathogenic oomycete Phytophthora parasitica and the mutualistic endophyte Serendipita indica, we determined root responses on a cell-layer resolution. These data reflect the fundamentally different colonization strategies of the microbes. Mining the data-set, we identified a Verticillium specific suppression of the endodermal barrier restricting fungal progression, localized biosynthesis of antimicrobial compounds, and observed a pathogen-specific arrest of root meristems correlated with ethylene biosynthesis. These examples highlight the power of this approach in generating testable hypotheses to gain insights into Root-microbe-interactions. Root cell-layer response to infection by three fungi with different lifestyles