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 the tale cress Arabidopsis thaliana 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 A. thaliana in response to the presence of P. annua. ESC1 encodes a proline-rich, extensin-like receptor kinase, also known as PERK13 (AT1G70460). An RNA-seq experiment revealed that PERK13 functions through different pathways in leaves and roots involving genes associated with responses to biotic and abiotic stresses. Using these RNA-seq together with yeast two-hybrid (Y2H) data, protein-protein interaction network reconstruction revealed two distinct decentralized protein networks in leaves and roots. These findings support the notion of an active response mechanism involved in neighbor detection. The functional validation of ESC-1 underlying natural variation in response to competition opens new avenues for a better understanding of the molecular dialogue involved in plant-plant interactions. Significance statementAlthough competition among plant species significantly impacts the performance of crops and wild plants, the genetic and molecular bases of natural variation in these interactions remain largely unknown. In this study, we cloned a receptor-like kinase involved in the response of Arabidopsis thaliana to various neighboring species. Through an integrated approach combining genetics, transcriptomics, and systems biology, we uncovered two distinct genetic pathways that support active mechanisms for neighbor detection in A. thaliana.