The Arabidopsis JAZ2 promoter contains a G-Box and thymidine-rich module that are necessary and sufficient for jasmonate-dependent activation by MYC transcription factors and repression by JAZ proteins

Plant Cell Physiol. 2012 Feb;53(2):330-43. doi: 10.1093/pcp/pcr178. Epub 2011 Dec 14.

Abstract

Jasmonate (JA) is a critical hormone for both plant defense and reproductive development. Until now, early JA-responsive promoters have not been well characterized. To identify the cis-acting DNA element involved in the early JA response at the transcriptional level, we analyzed the promoter of the Arabidopsis gene encoding jasmonate-ZIM domain2 protein (JAZ2). The full-length JAZ2 promoter in JAZ2::GUS plants is active in vegetative and reproductive tissue, with expression in stamen filaments being dependent on JA biosynthesis. We identified a G-box element in the JAZ2 promoter that is required for JA-mediated promoter activation in carrot protoplasts and Arabidopsis seedlings. Three copies of a G-box and flanking sequences has autonomous JA-dependent activity and was transactivated by MYC2, MYC3 and MYC4 transcription factors in carrot protoplasts. Expression of MYC2, MYC3 or MYC4 fused to an EAR (ETHYLENE RESPONSE FACTOR-associated amphiphilic repression) motif, or expression of JAZ1 or JAZ6 all repressed JA- and MYC-dependent activation of the JAZ2 promoter. A thymidine-rich sequence 3' to the G-box was required for full JA activation of the JAZ2 promoter. Because the G-box is also present in genes unresponsive to JA, we propose that this thymidine-rich sequence together with the G-box provides JA specificity to promoters induced early in the JA response. Together, these results indicate that an extended G-box located in the promoter region of an early JA-responsive gene is required for gene induction in vivo, probably through selective binding of MYC2, MYC3 and MYC4 transcription factors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Base Sequence
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / metabolism
  • Cyclopentanes / metabolism*
  • Daucus carota / genetics
  • Daucus carota / metabolism
  • Gene Expression Regulation, Plant
  • Oxylipins / metabolism*
  • Plant Growth Regulators / metabolism
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism
  • Promoter Regions, Genetic*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Thymidine / metabolism
  • Trans-Activators / metabolism

Substances

  • Arabidopsis Proteins
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • Cyclopentanes
  • JAZ2 protein, Arabidopsis
  • MYC2 protein, Arabidopsis
  • MYC3 protein, Arabidopsis
  • MYC4 protein, Arabidopsis
  • Oxylipins
  • Plant Growth Regulators
  • Repressor Proteins
  • Trans-Activators
  • jasmonic acid
  • Thymidine