Arabidopsis thaliana Raw sequence reads
Quorum sensing (QS) leads to bacterial population-wide coordination. How plants perceive QS signals remains elusive. Here, we report that 2-aminoacetophenone (2-AA), a QS metabolite emitted from Pseudomonas aeruginosa, not only shapes rhizosphere microbiota with ubiquitous repression on Pseudomonas genus, but also elicits plant immune responses through the perception by cell-surface pattern recognition receptor (PRR) complexes that require BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED KINASE (BAK1). 2-AA activates PRR-mediated immunity and primes plant resistance to Pseudomonas pathogens. The 2-AA-activated immunity displayed elicitor specificity to chemical structures and genetic specificity to the types of PRRs. 2-AA triggers in vivo protein interactions between BAK1 and its co-functioning PPRs, meanwhile the plant transcriptome responded to 2-AA similarly as to flg22, a bacterial immunogenic elicitor that activates BAK1-dependent immunity. Hence bacterial QS signals can be sensed by plant cell-surface immune receptors.