The plastid-nucleus located DNA/RNA binding protein WHIRLY1 regulates microRNA-levels during stress in barley (Hordeum vulgare L.)

RNA Biol. 2018;15(7):886-891. doi: 10.1080/15476286.2018.1481695. Epub 2018 Jul 14.


In this article a novel mechanism of retrograde signaling by chloroplasts during stress is described. This mechanism involves the DNA/RNA binding protein WHIRLY1 as a regulator of microRNA levels. By virtue of its dual localization in chloroplasts and the nucleus of the same cell, WHIRLY1 was proposed as an excellent candidate coordinator of chloroplast function and nuclear gene expression. Comparison of wild-type and transgenic plants with an RNAi-mediated knockdown of WHIRLY1 showed, that the transgenic plants were unable to cope with continuous high light conditions. They were impaired in production of several microRNAs mediating post-transcriptional responses during stress. The results support a central role of WHIRLY1 in retrograde signaling and also underpin a so far underestimated role of microRNAs in this process.

Keywords: Retrograde signaling; small RNA; stress response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Nucleus / metabolism
  • Chloroplasts / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Gene Expression Regulation, Plant
  • Gene Knockdown Techniques
  • Hordeum / genetics
  • Hordeum / physiology*
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Plant Leaves / growth & development
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plants, Genetically Modified / genetics
  • RNA, Plant / genetics
  • RNA, Plant / metabolism*
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*
  • Seedlings / growth & development
  • Seedlings / radiation effects
  • Stress, Physiological / physiology*


  • DNA-Binding Proteins
  • MicroRNAs
  • Plant Proteins
  • RNA, Plant
  • RNA-Binding Proteins

Grants and funding

This work was supported by the Deutsche Forschungsgemeinschaft [Kr1350/7]; Deutsche Forschungsgemeinschaft [Kr1350/9]; Narodowe Centrum Nauki [UMO-2016/23/B/NZ9/00862]; Ministerstwo Nauki i Szkolnictwa Wyższego, KNOW RNAResearch Centre in Poznan [01/ KNOW2/2014]; A. K. L. benefits from the support of the LabEx Saclay Plant Sciences-SPS (ANR-10-LABX-0040-SPS) and the French Infrastructure for Integrated Structural Biology (FRISBI) ANR-10-INSB-05.