Abscisic acid induces CBF gene transcription and subsequent induction of cold-regulated genes via the CRT promoter element

Many cold-regulated genes of Arabidopsis are inducible by abscisic acid (ABA) as well as by cold. This has been thought to occur via two separate signaling pathways, with ABA acting via ABA-responsive promoter elements and low temperature activating the C-repeat element (CRT; dehydration-responsive)...

Full description

Saved in:
Bibliographic Details
Published inPlant physiology (Bethesda) Vol. 135; no. 3; pp. 1710 - 1717
Main Authors Knight, H, Zarka, D.G, Okamoto, H, Thomashow, M.F, Knight, M.R
Format Journal Article
LanguageEnglish
Published Rockville, MD American Society of Plant Biologists 01.07.2004
American Society of Plant Physiologists
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:Many cold-regulated genes of Arabidopsis are inducible by abscisic acid (ABA) as well as by cold. This has been thought to occur via two separate signaling pathways, with ABA acting via ABA-responsive promoter elements and low temperature activating the C-repeat element (CRT; dehydration-responsive) promoter element via CBF (DREB1) transcription factors. We show here that ABA is also capable of activating the CRT promoter element. Although the more recently discovered ABA-inducible CBF4 transcription factor might have accounted for this, we show here that CBF1-3 transcript levels also increase in response to elevated ABA levels. This increase in CBF1-3 transcript levels appears to be at least in part due to increased activity of the CBF promoters in response to ABA. A total of 125 bp of the CBF2 promoter, which has previously been shown to be sufficient for cold-, mechanical-, and cycloheximide-induced expression, was also sufficient for ABA-induced expression. However, the ABA-responsive promoter element-like motif within this region is not needed for ABA-induced expression. An observed increase in CBF protein levels after ABA treatment, together with previous data showing that increased CBF levels are sufficient for cold-regulated gene induction, suggests that ABA-induced increases in CBF1-3 transcript levels do have the potential to activate the CRT. Our data indicate therefore that activation of the CRT may also occur via a novel ABA-inducible signaling pathway using the normally cold-inducible CBFs.
Bibliography:http://www.plantphysiol.org/
ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0032-0889
1532-2548
DOI:10.1104/pp.104.043562