Pathways & interactions
AP2/ERF domain (IPR001471)
Short name: AP2/ERF_dom
Overlapping homologous superfamilies
Ethylene is an endogenous plant hormone that influences many aspects of plant growth and development. Some defense related genes that are induced by ethylene contain a cis-regulatory element known as the Ethylene-Responsive Element (ERE) [PMID: 2535512]. Sequence analysis on various ERE regions has identified a short motif rich in G/C nucleotides, the GCC-box, essential for the response to ethylene. This short motif is recognised by a family of transcrition factors, the ERE binding factors (ERF) [PMID: 10715325].
ERF proteins contain a domain of around 60 amino acids which is also found in the APETALA2 (AP2) protein [PMID: 7773013]. This AP2/ERF domain has been shown in various proteins to be necessary and sufficient to bind the GCC-box [PMID: 9756931].
The structure of the AP2/ERF domain in complex with the target DNA has been solved [PMID: 9736626]. The structure resembles that of bacteriophage integrases and the methyl-CpG-binding domain (MBD): a three-stranded beta-sheet and an alpha helix almost parallel to the beta-sheet. It contacts DNA via Arg and Trp residues located in the beta-sheet.
Some proteins known to contain an AP2/ERF domain include:
- Arabidopsis thaliana ERF1 to 6.
- Tobacco ethylene-responsive element-binding proteins (EREBPs), homologues of ERF proteins.
- Arabidopsis thaliana AP2 protein. It regulates meristeme identity, floral organ specification and seed coat development.
- Arabidopsis thaliana C-repeat/dehydration-responsive element (DRE) binding factor 1 (CBF1 or DREB1) and DREB2. They bind a GCC-box-like element found in dehydratation responsive element. Binding to this element mediates cold-inducible transcription.
- Arabidopsis thaliana and maize abscisic acid (ABA)-insensitive 4 (ABI4) proteins. They bind to a GCC-box-like element found in ABA-responsive genes.
- Octadecanoid-derivative responsive catharenthus AP2-domain (ORCA2) protein. It binds a GCC-box-like element in the jasmonate responsive element of Str promoter.
- Tomato Pto-interacting proteins 4 to 6 (Pti4 to Pti6). Pti5 and 6 bind a GCC-box-like element in regulatory regions of various pathogenesis-related (PR) genes.
- Trichodesmium erythraeum, Tetrahymena thermophila, Enterobacteria phage RB49 and bacteriophage Felix 01 HNH endonucleases. HNH endonucleases are homing endonucleases that move extensively via lateral gene transfer [PMID: 15319480].
This entry represents the AP2/ERF domain.