A novel chemical inhibitor of ABA signaling targets all ABA receptors

Chemical genetics is an approach that enables small molecules with specific effects on phenotypes to be identified. Through a screen for small molecules that would reverse the inhibitory effect of ABA on seed germination, Ye et al. identified AA1 (ABA Antagonist 1). AA1 interferes with the interaction between all of the ABA PYR-PYL receptors and their associated PP2C phosphatases. AA1 is a broad-spectrum ABA antagonist that inhibits numerous ABA responses including gene expression, leaf senescence, fruit ripening and stomatal closure, providing a new tool for research and agriculture. Plant Physiol. ​10.​1104/​pp.​16.​01862