Constitutive activation of ABA receptors in Arabidopsis reveals unique regulatory circuitries

Oded Pri-Tal, Yufei Sun, Armin Dadras, Janine M.R. Fürst-Jansen, Gil Zimran, Daphna Michaeli, Akila Wijerathna-Yapa, Michal Shpilman, Ebe Merilo, Dmitry Yarmolinsky, Idan Efroni, Jan de Vries, Hannes Kollist, Assaf Mosquna*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Abscisic acid (ABA) is best known for regulating the responses to abiotic stressors. Thus, applications of ABA signaling pathways are considered promising targets for securing yield under stress. ABA levels rise in response to abiotic stress, mounting physiological and metabolic responses that promote plant survival under unfavorable conditions. ABA elicits its effects by binding to a family of soluble receptors found in monomeric and dimeric states, differing in their affinity to ABA and co-receptors. However, the in vivo significance of the biochemical differences between these receptors remains unclear. We took a gain-of-function approach to study receptor-specific functionality. First, we introduced activating mutations that enforce active ABA-bound receptor conformation. We then transformed Arabidopsis ABA-deficient mutants with the constitutive receptors and monitored suppression of the ABA deficiency phenotype. Our findings suggest that PYL4 and PYL5, monomeric ABA receptors, have differential activity in regulating transpiration and transcription of ABA biosynthesis and stress response genes. Through genetic and metabolic data, we demonstrate that PYR1, but not PYL5, is sufficient to activate the ABA positive feedback mechanism. We propose that ABA signaling – from perception to response – flows differently when triggered by different PYLs, due to tissue and transcription barriers, thus resulting in distinct circuitries.

Original languageAmerican English
Pages (from-to)703-714
Number of pages12
JournalNew Phytologist
Volume241
Issue number2
DOIs
StatePublished - Jan 2024

Bibliographical note

Publisher Copyright:
© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.

Keywords

  • PYR/PYL/RCAR
  • abscisic acid
  • plant stress response
  • signal transduction
  • stomata regulation

Fingerprint

Dive into the research topics of 'Constitutive activation of ABA receptors in Arabidopsis reveals unique regulatory circuitries'. Together they form a unique fingerprint.

Cite this