A non-DNA-binding activity for the ATHB4 transcription factor in the control of vegetation proximity
Gallemí, Marçal (Centre de Recerca en Agrigenòmica)
Molina-Contreras, Maria Jose (Centre de Recerca en Agrigenòmica)
Paulišić, Sandi (Centre de Recerca en Agrigenòmica)
Salla Martret, Mercè (Centre de Recerca en Agrigenòmica)
Sorin, Céline (Centre de Recerca en Agrigenòmica)
Godoy, Marta (Centro Nacional de Biotecnología (Espanya))
Franco-Zorrilla, Jose Manuel (Centro Nacional de Biotecnología (Espanya))
Solano, Roberto (Centro Nacional de Biotecnología (Espanya))
Martínez García, Jaime F. (Centre de Recerca en Agrigenòmica)

Date:	2017
Abstract:	In plants, perception of vegetation proximity by phytochrome photoreceptors activates a transcriptional network that implements a set of responses to adapt to plant competition, including elongation of stems or hypocotyls. In Arabidopsis thaliana, the homeodomain-leucine zipper (HD-Zip) transcription factor ARABIDOPSIS THALIANA HOMEOBOX 4 (ATHB4) regulates this and other responses, such as leaf polarity. To better understand the shade regulatory transcriptional network, we have carried out structure-function analyses of ATHB4 by overexpressing a series of truncated and mutated forms and analyzing three different responses: hypocotyl response to shade, transcriptional activity and leaf polarity. Our results indicated that ATHB4 has two physically separated molecular activities: that performed by HD-Zip, which is involved in binding to DNA-regulatory elements, and that performed by the ETHYLENE-RESPONSIVE ELEMENT BINDING FACTOR-associated amphiphilic repression (EAR)-containing N-terminal region, which is involved in protein-protein interaction. Whereas both activities are required to regulate leaf polarity, DNA-binding activity is not required for the regulation of the seedling responses to plant proximity, which indicates that ATHB4 works as a transcriptional cofactor in the regulation of this response. These findings suggest that transcription factors might employ alternative mechanisms of action to regulate different developmental processes.
Grants:	Ministerio de Economía y Competitividad SEV-2015-0533 Ministerio de Economía y Competitividad BIO2014-59895-P Ministerio de Economía y Competitividad BIO2011-23489 Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-447
Note:	Altres ajuts: Generalitat de Catalunya through the CERCA Program
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Arabidopsis thaliana ; Arabidopsis thaliana homeobox 4 (ATHB4) ; DNA-binding activity ; Ethylene-responsive element binding factor-associated amphiphilic repression (EAR) motif ; Homeodomain-leucine zipper ; Shade avoidance syndrome
Published in:	The new phytologist, Vol. 216, issue 3 (Nov. 2017) , p. 798-813, ISSN 1469-8137

DOI: 10.1111/nph.14727

Post-print. Article 41 p, 15.2 MB

Post-print. Supplementary material 29 p, 2.2 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > CRAG (Centre for Research in Agricultural Genomics)
Articles > Research articles
Articles > Published articles