CONSTITUTIVELY PHOTOMORPHOGENIC1 promotes ABA-mediated inhibition of post-germination seedling establishment.
Arabidopsis thaliana
ABI5
COP1
abscisic acid
hormone signaling
light signaling
seedling development
Journal
The Plant journal : for cell and molecular biology
ISSN: 1365-313X
Titre abrégé: Plant J
Pays: England
ID NLM: 9207397
Informations de publication
Date de publication:
07 2020
07 2020
Historique:
received:
18
10
2019
accepted:
12
05
2020
pubmed:
22
5
2020
medline:
6
3
2021
entrez:
22
5
2020
Statut:
ppublish
Résumé
Under acute stress conditions, precocious seedling development may result in the premature death of young seedlings, before they switch to autotrophic growth. The phytohormone abscisic acid (ABA) inhibits seed germination and post-germination seedling establishment under unfavorable conditions. Various environmental signals interact with the ABA pathway to optimize these early developmental events under stress. Here, we show that light availability critically influences ABA sensitivity during early seedling development. In dark conditions, the ABA-mediated inhibition of post-germination seedling establishment is strongly enhanced. COP1, a central regulator of seedling development in the dark, is necessary for this enhanced post-germination ABA sensitivity in darkness. Despite their slower germination, cop1 seedlings establish faster than wild type in the presence of ABA in both light and dark. PHY and CRY photoreceptors that inhibit COP1 activity in light modulate ABA-mediated inhibition of seedling establishment in light. Genetically, COP1 acts downstream to ABI5, a key transcriptional regulator of ABA signaling, and does not influence the transcriptional and protein levels of ABI5 during the early post-germination stages. COP1 promotes post-germination growth arrest independent of the antagonistic interaction between ABA and cytokinin signaling pathways. COP1 facilitates the binding of ABI5 on its target promoters and the ABA-mediated upregulation of these target genes is reduced in cop1-4. Together, our results suggest that COP1 positively regulates ABA signaling to inhibit post-germination seedling establishment under stress.
Substances chimiques
ABI5 protein, Arabidopsis
0
Arabidopsis Proteins
0
Basic-Leucine Zipper Transcription Factors
0
Cytokinins
0
Plant Growth Regulators
0
Abscisic Acid
72S9A8J5GW
AT2G32950 protein, Arabidopsis
EC 2.3.2.27
Ubiquitin-Protein Ligases
EC 2.3.2.27
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
481-496Commentaires et corrections
Type : CommentIn
Informations de copyright
© 2020 Society for Experimental Biology and John Wiley & Sons Ltd.
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