An Arabidopsis receptor-like kinase mediates competitive plant-plant interactions

While competition among plant species is recognized as a major factor affecting crop yield and plant community dynamics, the genetic and molecular mechanisms underlying natural variation of such biotic interactions remain poorly characterized. Here, we report the cloning of a quantitative trait locus previously detected in a genome-wide association study investigating the competitive response of Arabidopsis to the presence of the annual bluegrass weed species Poa annua. Using mutant and complementation strategies, we identified ESCAPE 1 (ESC1) as the gene responsible for the natural variation of an escape strategy of Arabidopsis in response to the presence of P. annua. ESC1 encodes a proline-rich, extensin-like receptor kinase, also known as PERK13. RNA-sequencing revealed that PERK13 functions through different pathways in leaves and roots, involving genes associated with responses to biotic and abiotic stresses. Using the RNA-seq data together with results from yeast two-hybrid assays, protein-protein interaction network reconstruction revealed two distinct decentralized protein networks in leaves and roots. Our findings support the notion of an active response mechanism involved in neighbor detection. The functional validation of ESC1 underlying natural variation in response to competition opens new avenues for a better understanding of the molecular dialogue involved in plant-plant interactions.