KARRIKIN UP-REGULATED F-BOX 1 (KUF1) imposes negative feedback regulation of karrikin and KAI2 ligand metabolism in Arabidopsis thaliana

Proc Natl Acad Sci U S A. 2022 Mar 15;119(11):e2112820119. doi: 10.1073/pnas.2112820119. Epub 2022 Mar 7.

Abstract

SignificanceKarrikins are chemicals in smoke that stimulate regrowth of many plants after fire. However, karrikin responses are not limited to species from fire-prone environments and can affect growth after germination. Putatively, this is because karrikins mimic an unknown signal in plants, KAI2 ligand (KL). Karrikins likely require modification in plants to become bioactive. We identify a gene, KUF1, that appears to negatively regulate biosynthesis of KL and metabolism of a specific karrikin. KUF1 expression increases in response to karrikin or KL signaling, thus forming a negative feedback loop that limits further activation of the signaling pathway. This discovery will advance understanding of how karrikins are perceived and how smoke-activated germination evolved. It will also aid identification of the elusive KL.

Keywords: biosynthesis; photomorphogenesis; plant hormones; proteolysis; signaling.

MeSH terms

  • Arabidopsis / drug effects*
  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Furans / pharmacology*
  • Gene Expression Regulation, Plant / drug effects*
  • Genes, Plant*
  • Hydrolases / genetics*
  • Pyrans / pharmacology*
  • Seedlings / genetics
  • Seedlings / metabolism
  • Signal Transduction

Substances

  • 3-methyl-2H-furo(2,3-c)pyran-2-one
  • Arabidopsis Proteins
  • Furans
  • Pyrans
  • HTL protein, Arabidopsis
  • Hydrolases