Redox feedback regulation of ANAC089 signaling alters seed germination and stress response

Cell Rep. 2021 Jun 15;35(11):109263. doi: 10.1016/j.celrep.2021.109263.

Abstract

The interplay between the phytohormone abscisic acid (ABA) and the gasotransmitter nitric oxide (NO) regulates seed germination and post-germinative seedling growth. We show that GAP1 (germination in ABA and cPTIO 1) encodes the transcription factor ANAC089 with a critical membrane-bound domain and extranuclear localization. ANAC089 mutants lacking the membrane-tethered domain display insensitivity to ABA, salt, and osmotic and cold stresses, revealing a repressor function. Whole-genome transcriptional profiling and DNA-binding specificity reveals that ANAC089 regulates ABA- and redox-related genes. ANAC089 truncated mutants exhibit higher NO and lower ROS and ABA endogenous levels, alongside an altered thiol and disulfide homeostasis. Consistently, translocation of ANAC089 to the nucleus is directed by changes in cellular redox status after treatments with NO scavengers and redox-related compounds. Our results reveal ANAC089 to be a master regulator modulating redox homeostasis and NO levels, able to repress ABA synthesis and signaling during Arabidopsis seed germination and abiotic stress.

Keywords: abiotic stress; abscisic acid; nitric oxide; redox homeostasis; seed; transcription factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / metabolism
  • Arabidopsis Proteins* / genetics
  • Arabidopsis Proteins* / metabolism
  • Arabidopsis* / genetics
  • Arabidopsis* / physiology
  • Base Sequence
  • Binding Sites
  • DNA, Plant / metabolism
  • Disulfides / metabolism
  • Down-Regulation / genetics
  • Feedback, Physiological*
  • Gain of Function Mutation / genetics
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant
  • Germination* / genetics
  • Nitric Oxide / metabolism
  • Oxidation-Reduction
  • Protein Binding
  • Seeds* / genetics
  • Seeds* / growth & development
  • Signal Transduction*
  • Stress, Physiological*
  • Subcellular Fractions / metabolism
  • Sulfhydryl Compounds / metabolism
  • Transcriptome / genetics
  • Up-Regulation / genetics

Substances

  • Abscisic Acid
  • Arabidopsis Proteins
  • Disulfides
  • DNA, Plant
  • Nitric Oxide
  • Sulfhydryl Compounds
  • AT5G22090 protein, Arabidopsis