Mutual regulation of Arabidopsis thaliana ethylene-responsive element binding protein and a plant floral homeotic gene, APETALA2

Ann Bot. 2007 Feb;99(2):239-44. doi: 10.1093/aob/mcl265. Epub 2007 Jan 4.


Background and aims: It has previously been shown that Arabidopsis thaliana ethylene-responsive element binding protein (AtEBP) contributed to resistance to abiotic stresses. Interestingly, it has also been reported that expression of ethylene-responsive factor (ERF) genes including AtEBP were regulated by the activity of APETALA2 (AP2), a floral homeotic factor. AP2 is known to regulate expression of several floral-specific homeotic genes such as AGAMOUS. The aim of this study was to clarify the relationship between AP2 and AtEBP in gene expression.

Methods: Northern blot analysis was performed on ap2 mutants, ethylene-related Arabidopsis mutants and transgenic Arabidopsis plants over-expressing AtEBP, and a T-DNA insertional mutant of AtEBP. Phenotypic analysis of these plants was performed.

Key results: Expression levels of ERF genes such as AtEBP and AtERF1 were increased in ap2 mutants. Over-expression of AtEBP caused upregulation of AP2 expression in leaves. AP2 expression was suppressed by the null-function of ethylene-insensitive2 (EIN2), although AP2 expression was not affected by ethylene treatment. Loss of AtEBP function slightly reduced the average number of stamens.

Conclusions: AP2 and AtEBP are mutually regulated in terms of gene expression. AP2 expression was affected by EIN2 but was not regulated by ethylene treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Flowers / anatomy & histology
  • Flowers / genetics
  • Flowers / metabolism
  • Gene Deletion
  • Gene Expression Regulation, Plant*
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • RNA, Messenger / metabolism
  • Up-Regulation


  • APETALA2 protein, Arabidopsis
  • Arabidopsis Proteins
  • DNA-Binding Proteins
  • Homeodomain Proteins
  • Nuclear Proteins
  • Plant Proteins
  • RNA, Messenger
  • ethylene-responsive element binding protein