A MAPK pathway mediates ethylene signaling in plants

Fatma Ouaked, Wilfried Rozhon, David Lecourieux, Heribert Hirt*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

232 Scopus citations


Ethylene signal transduction involves ETR1, a two-component histidine protein kinase receptor. ETR1 functions upstream of the negative regulator CTR1. The similarity of CTR1 to members of the Raf family of mitogen-activated protein kinase kinase kinases (MAPKKKs) suggested that ethylene signaling in plants involves a MAPK pathway, but no direct evidence for this has been provided. Here we show that distinct MAPKs are activated by the ethylene precursor aminocyclopropane-1-carboxylic acid (ACC) in Medicago and Arabidopsis. In Medicago, the ACC-activated MAPKs were SIMK and MMK3, while in Arabidopsis MPK6 and another MAPK were identified. Medicago SIMKK specifically mediated ACC-induced activation of SIMK and MMK3. Transgenic Arabidopsis plants overexpressing SIMKK have constitutive MPK6 activation and ethylene-induced target gene expression. SIMKK overexpressor lines resemble ctr1 mutants in showing a triple response phenotype in the absence of ACC. Whereas MPK6 was not activated by ACC in etr1 mutants, ein2 and ein3 mutants showed normal activation profiles. In contrast, ctr1 mutants showed constitutive activation of MPK6. These data indicate that a MAPK cascade is part of the ethylene signal transduction pathway in plants.

Original languageEnglish (US)
Pages (from-to)1282-1288
Number of pages7
Issue number6
StatePublished - Mar 17 2003
Externally publishedYes


  • CTR1
  • ETR1
  • Ethylene
  • Gene expression
  • MAPK
  • Plant

ASJC Scopus subject areas

  • General Neuroscience
  • Molecular Biology
  • General Biochemistry, Genetics and Molecular Biology
  • General Immunology and Microbiology


Dive into the research topics of 'A MAPK pathway mediates ethylene signaling in plants'. Together they form a unique fingerprint.

Cite this