Overexpression of the auxin binding PROTEIN1 modulates PIN-dependent auxin transport in tobacco cells Journal Article

Author(s): Čovanová, Milada; Sauer, Michael; Rychtář, Jan; Friml, Jiří; Petrášek, Jan; Zažímalová, Eva
Article Title: Overexpression of the auxin binding PROTEIN1 modulates PIN-dependent auxin transport in tobacco cells
Affiliation IST Austria
Abstract: Background:Auxin binding protein 1 (ABP1) is a putative auxin receptor and its function is indispensable for plant growth and development. ABP1 has been shown to be involved in auxin-dependent regulation of cell division and expansion, in plasma-membrane-related processes such as changes in transmembrane potential, and in the regulation of clathrin-dependent endocytosis. However, the ABP1-regulated downstream pathway remains elusive.Methodology/Principal Findings:Using auxin transport assays and quantitative analysis of cellular morphology we show that ABP1 regulates auxin efflux from tobacco BY-2 cells. The overexpression of ABP1can counterbalance increased auxin efflux and auxin starvation phenotypes caused by the overexpression of PIN auxin efflux carrier. Relevant mechanism involves the ABP1-controlled vesicle trafficking processes, including positive regulation of endocytosis of PIN auxin efflux carriers, as indicated by fluorescence recovery after photobleaching (FRAP) and pharmacological manipulations.Conclusions/Significance:The findings indicate the involvement of ABP1 in control of rate of auxin transport across plasma membrane emphasizing the role of ABP1 in regulation of PIN activity at the plasma membrane, and highlighting the relevance of ABP1 for the formation of developmentally important, PIN-dependent auxin gradients.
Journal Title: PLoS One
Volume: 8
Issue 7
ISSN: 1932-6203
Publisher: Public Library of Science  
Date Published: 2013-07-01
Start Page: Article number: 70050
Copyright Statement: CC-BY
Sponsor: The work was supported by the Grant Agency of the Czech Republic, projects P305/11/0797 (to E.Z.) and P501/12/P951 (to M.Č.).
DOI: 10.1371/journal.pone.0070050
Notes: We thank Catherine Perrot-Rechenmann for providing the NtABP1 gene construct, Richard Napier for valuable discussions, David Cháb and Karel Müller for their help with data evaluation from quantitative RT-PCR, Martin Čovan and Michal Hála for many useful suggestions, and Jan Marc for critical reading of the manuscript.
Open access: yes (OA journal)