Skip Navigation



Plant and Cell Physiology Advance Access published online on July 14, 2005
Plant and Cell Physiology, doi:10.1093/pcp/pci162
This Article
Right arrow Advance Access manuscript (PDF)
Right arrow All Versions of this Article:
46/9/1494    most recent
pci162v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Zhang, Z.
Right arrow Articles by Rona, J.-P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Zhang, Z.
Right arrow Articles by Rona, J.-P.
Agricola
Right arrow Articles by Zhang, Z.
Right arrow Articles by Rona, J.-P.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Plant and Cell Physiology 2005 © The Japanese Society of Plant Physiologists (JSPP); all rights reserved.
Received May 13, 2005
Accepted July 5, 2005

Regular Paper

Brassinosteroids Regulate Plasma Membrane Anion Channels in Addition to Proton Pumps During Expansion of Arabidopsis thaliana Cells

Zongshen Zhang 1, Javier Ramirez 2, David Reboutier 1, Mathias Brault 1, Jacques Trouverie 1, Anne-Marie Pennarun 1, Zahia Amiar 1, Bernadette Biligui 1, Lydia Galagovsky 2, and Jean-Pierre Rona 1*

1 Laboratoire d'Electrophysiologie des Membranes, EA 3514, Université Paris 7, 2 Place Jussieu, 75251 Paris Cedex 05, France
2 Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina

* To whom correspondence should be addressed.
Jean-Pierre Rona, E-mail: jprona{at}ccr.jussieu.fr


  Abstract

Brassinosteroids (BRs) are involved in numerous physiological processes associated with plant development and especially with cell expansion. In this paper we report that two BRs, 28-homobrassinolide (HBL) and its direct precursor 28-homocastasterone (HCS), promote cell expansion of Arabidopsis thaliana suspension cells. We also show that cell expansions induced by HBL and HCS are correlated with the amplitude of the PM hyperpolarization they elicited. HBL, which promoted the larger cell expansion, also provoked the larger hyperpolarization. We observed that membrane hyperpolarization and cell expansion were partially inhibited by the proton pump inhibitor erythrosin B, suggesting that proton pumps were not the only ion transport system modulated by the two BRs. We used a voltage clamp approach in order to find the other ion transport systems involved in the PM hyperpolarization elicited by HBL and HCS. Interestingly, while anion currents were inhibited by both HBL and HCS, outward rectifying K+ currents were increased by HBL but inhibited by HCS. The different electrophysiological behaviour, shown by HBL and HCS, indicate that small changes in the BR skeleton might be responsible for changes in bioactivity.

Keywords: Arabidopsis thaliana; brassinosteroid; ion currents; PM; proton pump; suspension cells.
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.