A lncRNA fine-tunes salicylic acid biosynthesis to balance plant immunity and growth

Cell Host Microbe. 2022 Aug 10;30(8):1124-1138.e8. doi: 10.1016/j.chom.2022.07.001. Epub 2022 Jul 30.

Abstract

Constitutive activation of plant immunity is detrimental to plant growth and development. Here, we uncover the role of a long non-coding RNA (lncRNA) in fine-tuning the balance of plant immunity and growth. We find that a lncRNA termed salicylic acid biogenesis controller 1 (SABC1) suppresses immunity and promotes growth in healthy plants. SABC1 recruits the polycomb repressive complex 2 to its neighboring gene NAC3, which encodes a NAC transcription factor, to decrease NAC3 transcription via H3K27me3. NAC3 activates the transcription of isochorismate synthase 1 (ICS1), a key enzyme catalyzing salicylic acid (SA) biosynthesis. SABC1 thus represses SA production and plant immunity via decreasing NAC3 and ICS1 transcriptions. Upon pathogen infection, SABC1 is downregulated to derepress plant resistance to bacteria and viruses. Together, our findings reveal lncRNA SABC1 as a molecular switch in balancing plant defense and growth by modulating SA biosynthesis.

Keywords: H3K27me3; ICS1; NAC3; SABC1; bacteria; chromatin loop; lncRNA; plant immunity and growth balance; salicylic acid; viruses.

MeSH terms

  • Arabidopsis Proteins* / genetics
  • Arabidopsis Proteins* / metabolism
  • Arabidopsis* / microbiology
  • Gene Expression Regulation, Plant
  • Plant Diseases
  • Plant Immunity / physiology
  • Plants / genetics
  • RNA, Long Noncoding* / genetics
  • Salicylic Acid

Substances

  • Arabidopsis Proteins
  • RNA, Long Noncoding
  • Salicylic Acid