Plant perception of β-aminobutyric acid is mediated by an aspartyl-tRNA synthetase.
Specific chemicals can prime the plant immune system for augmented defense. β-aminobutyric acid (BABA) is a priming agent that provides broad-spectrum disease protection. However, BABA also suppresses plant growth when applied in high doses, which has hampered its application as a crop defense activator. Here we describe a mutant of Arabidopsis thaliana that is impaired in BABA-induced disease immunity (ibi1) but is hypersensitive to BABA-induced growth repression. IBI1 encodes an aspartyl-tRNA synthetase. Enantiomer-specific binding of the R enantiomer of BABA to IBI1 primed the protein for noncanonical defense signaling in the cytoplasm after pathogen attack. This priming was associated with aspartic acid accumulation and tRNA-induced phosphorylation of translation initiation factor eIF2α. However, mutation of eIF2α-phosphorylating GCN2 kinase did not affect BABA-induced immunity but relieved BABA-induced growth repression. Hence, BABA-activated IBI1 controls plant immunity and growth via separate pathways. Our results open new opportunities to separate broad-spectrum disease resistance from the associated costs on plant growth.
1] Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, UK. [2] Rothamsted Research, Harpenden, UK.
Estrella
E
Luna
Department of Biology, Utrecht University, Utrecht, The Netherlands.
Marieke
M
van Hulten
1] Rothamsted Research, Harpenden, UK. [2].
Yuhua
Y
Zhang
1] Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Perth, Australia. [2] School of Plant Biology, University of Western Australia, Perth, Australia.
Oliver
O
Berkowitz
Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, UK.
Ana
A
López
Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, UK.
Pierre
P
Pétriacq
Department of Chemistry, University of Sheffield, Sheffield, UK.
Matthew A
MA
Sellwood
Department of Chemistry, University of Sheffield, Sheffield, UK.
Beining
B
Chen
Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, UK.
Mike
M
Burrell
1] Rothamsted Research, Harpenden, UK. [2].
Allison
A
van de Meene
Department of Biology, Utrecht University, Utrecht, The Netherlands.
Corné M J
0000000254734646
CM
Pieterse
Departmento de Ciencias Agrarias y del Medio Ambiente, University of Jaume I, Castellon, Spain.
Victor
V
Flors
1] Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, UK. [2] Rothamsted Research, Harpenden, UK. [3] Department of Biology, Utrecht University, Utrecht, The Netherlands.
Jurriaan
J
Ton
D000613:Aminobutyrates / Q000737:chemistry / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D001226:Aspartate-tRNA Ligase / Q000235:genetics* / Q000378:metabolism*; D017343:Genes, Plant; D009154:Mutation; D010935:Plant Diseases / Q000276:immunology / Q000517:prevention & control; D057865:Plant Immunity / Q000187:drug effects / Q000235:genetics; D013237:Stereoisomerism
D000613:Aminobutyrates; C047667:3-aminobutyric acid; D001226:Aspartate-tRNA Ligase