Trans-Golgi network localized small GTPase RabA1d is involved in cell plate formation and oscillatory root hair growth

BMC Plant Biology

Research Article

Daniel von Wangenheim¹  Ernst HK Stelzer¹  Jozef Šamaj²  Olga Šamajová²  George Komis²  Amparo Rosero²  Miroslav Ovečka²  Tomáš Takáč²  Tobias Berson³ 

[1] Buchmann Institute for Molecular Life Sciences, Goethe-Universität Frankfurt am Main, Max-von-Laue-Str. 15, 60438, Frankfurt am Main, Germany;Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Cell Biology, Faculty of Science, Palacký University, Šlechtitelů 11, 783 71, Olomouc, Czech Republic;Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, D-53115, Bonn, Germany;

关键词: Arabidopsis;    Cell plate;    Cytokinesis;    Rab GTPase;    Localization;    RabA1d;    Root hair;    Trans-Golgi network;    Vesicle;   

DOI  :  10.1186/s12870-014-0252-0

 received in 2014-07-10, accepted in 2014-09-18,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundSmall Rab GTPases are important regulators of vesicular trafficking in plants. AtRabA1d, a member of the RabA1 subfamily of small GTPases, was previously found in the vesicle-rich apical dome of growing root hairs suggesting a role during tip growth; however, its specific intracellular localization and role in plants has not been well described.ResultsThe transient expression of 35S::GFP:RabA1d construct in Allium porrum and Nicotiana benthamiana revealed vesicular structures, which were further corroborated in stable transformed Arabidopsis thaliana plants. GFP-RabA1d colocalized with the trans-Golgi network marker mCherry-VTI12 and with early FM4-64-labeled endosomal compartments. Late endosomes and endoplasmic reticulum labeled with FYVE-DsRed and ER-DsRed, respectively, were devoid of GFP-RabA1d. The accumulation of GFP-RabA1d in the core of brefeldin A (BFA)-induced-compartments and the quantitative upregulation of RabA1d protein levels after BFA treatment confirmed the association of RabA1d with early endosomes/TGN and its role in vesicle trafficking. Light-sheet microscopy revealed involvement of RabA1d in root development. In root cells, GFP-RabA1d followed cell plate expansion consistently with cytokinesis-related vesicular trafficking and membrane recycling. GFP-RabA1d accumulated in disc-like structures of nascent cell plates, which progressively evolved to marginal ring-like structures of the growing cell plates. During root hair growth and development, GFP-RabA1d was enriched at root hair bulges and at the apical dome of vigorously elongating root hairs. Importantly, GFP-RabA1d signal intensity exhibited an oscillatory behavior in-phase with tip growth. Progressively, this tip localization dissapeared in mature root hairs suggesting a link between tip localization of RabA1d and root hair elongation. Our results support a RabA1d role in events that require vigorous membrane trafficking.ConclusionsRabA1d is located in early endosomes/TGN and is involved in vesicle trafficking. RabA1d participates in both cell plate formation and root hair oscillatory tip growth. The specific GFP-RabA1d subcellular localization confirms a correlation between its specific spatio-temporal accumulation and local vesicle trafficking requirements during cell plate and root hair formation.

【 授权许可】

Unknown   
© Berson et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.