Abscisic Acid Derivatives with Different Alkyl Chain Lengths Activate Distinct Abscisic Acid Receptor Subfamilies

ACS Chem Biol. 2019 Sep 20;14(9):1964-1971. doi: 10.1021/acschembio.9b00453. Epub 2019 Sep 9.


The plant hormone abscisic acid (ABA) regulates the development of various plant organs including seeds, roots, and fruits, and significantly contributes to abiotic stress responses, especially to drought. Since recent climate changes are adversely affecting crop cultivation, enhancement of plant stress tolerance by regulation of ABA signaling would be an important strategy. In the plant genome, ABA receptors are encoded by multiple genes constituting three subfamilies; however, functional differences among them remain unclear. To enhance desired effects of ABA, the biological functions of the receptor family warrant clarification. This study aimed to determine the functional differences among ABA receptors in plants. We screened small-molecule ligands binding to specific receptors, using a chemical array. In vitro evaluation of hit compounds using 11 Arabidopsis ABA receptors revealed that (+)-3'-alkyl ABAs served as agonists for different receptors depending on the length of their 3'-alkyl chains. Combinatorial in vitro and physiological effects of these compounds on the stomata, seeds, and seedlings indicated that, along with subfamily III, receptors of subfamily II are important to induce strong drought responses. Among (+)-3'-alkyl ABAs assessed herein, (+)-3'-butyl ABA induced a transcriptional response and stomatal closure but only slightly inhibited seed germination and growth, suggesting that it enhances drought tolerance. In silico docking simulation and site-directed mutagenesis revealed the amino acid residues contributing to the selective agonist activity of the (+)-3'-alkyl ABAs. These results provide novel insights into the structure and biological effects of 3'-derivatives of ABA and a basis for agrochemical development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / analogs & derivatives*
  • Abscisic Acid / metabolism
  • Arabidopsis / chemistry
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / agonists
  • Arabidopsis Proteins / antagonists & inhibitors
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Germination / drug effects
  • Intracellular Signaling Peptides and Proteins / agonists
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Membrane Transport Proteins / agonists
  • Membrane Transport Proteins / metabolism*
  • Molecular Docking Simulation
  • Molecular Structure
  • Mutagenesis, Site-Directed
  • Mutation
  • Phosphoprotein Phosphatases / antagonists & inhibitors
  • Plant Leaves / metabolism
  • Protein Binding
  • RNA, Messenger / metabolism
  • Receptors, Cell Surface / agonists
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Structure-Activity Relationship


  • Arabidopsis Proteins
  • Intracellular Signaling Peptides and Proteins
  • Membrane Transport Proteins
  • PYL10 protein, Arabidopsis
  • PYL5 protein, Arbaidopsis
  • Pyr1 protein, Arabidopsis
  • RNA, Messenger
  • Receptors, Cell Surface
  • Abscisic Acid
  • HAB1 protein, Arabidopsis
  • Phosphoprotein Phosphatases