β-Aminobutyric acid (BABA) is a small-molecule activator of plant disease resistance. Binding of (R)-BABA to IBI1—an aspartyl-tRNA synthetase (AspRS)—primes noncanonical defense pathways, resulting in broad-spectrum disease resistance. Ligand binding also blocks AspRS activity, leading to accumulation of aspartic acid and uncharged tRNA, which activate a second plant stress response.
- Estrella Luna
- Marieke van Hulten
- Jurriaan Ton
