Antagonistic activities of cotranscriptional regulators within an early developmental window set FLC expression level

Proc Natl Acad Sci U S A. 2021 Apr 27;118(17):e2102753118. doi: 10.1073/pnas.2102753118.

Abstract

Quantitative variation in expression of the Arabidopsis floral repressor FLC influences whether plants overwinter before flowering, or have a rapid cycling habit enabling multiple generations a year. Genetic analysis has identified activators and repressors of FLC expression but how they interact to set expression level is poorly understood. Here, we show that antagonistic functions of the FLC activator FRIGIDA (FRI) and the repressor FCA, at a specific stage of embryo development, determine FLC expression and flowering. FRI antagonizes an FCA-induced proximal polyadenylation to increase FLC expression and delay flowering. Sector analysis shows that FRI activity during the early heart stage of embryo development maximally delays flowering. Opposing functions of cotranscriptional regulators during an early embryonic developmental window thus set FLC expression levels and determine flowering time.

Keywords: Arabidopsis FLC; cotranscriptional regulation; embryogenesis; sector analysis; transcript isoforms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / embryology
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / metabolism*
  • Embryonic Development
  • Flowers / growth & development
  • Gene Expression Regulation, Plant*
  • MADS Domain Proteins / metabolism*
  • Polyadenylation
  • RNA-Binding Proteins / metabolism*

Substances

  • Arabidopsis Proteins
  • FLF protein, Arabidopsis
  • FRI protein, Arabidopsis
  • Flowering time control protein FCA, Arabidopsis
  • MADS Domain Proteins
  • RNA-Binding Proteins