This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 17/7/2020    most recent tpc.105.031112v2 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via ISI Web of Science (16) Citing Articles via Google Scholar Google Scholar Articles by Zheng, H. Articles by Moore, I. Search for Related Content PubMed PubMed Citation Articles by Zheng, H. Articles by Moore, I. Agricola Articles by Zheng, H. Articles by Moore, I.

A Rab-E GTPase Mutant Acts Downstream of the Rab-D Subclass in Biosynthetic Membrane Traffic to the Plasma Membrane in Tobacco Leaf Epidermis

^a Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, United Kingdom
^b Integrative Cell Biology Laboratory, School of Biological and Biomedical Sciences, University of Durham, Durham, DH1 3LE, United Kingdom
^c Universidade de Lisboa, Faculdade de Ciências de Lisboa, Instituto de Ciencia Aplicada e Tecnologia, 1749-016 Lisboa, Portugal

³ To whom correspondence should be addressed. E-mail ian.moore{at}plants.ox.ac.uk; fax 44-1865-275074.

The function of the Rab-E subclass of plant Rab GTPases in membrane traffic was investigated using a dominant-inhibitory mutant (RAB-E1^d[NI]) of Arabidopsis thaliana RAB-E1^d and in vivo imaging approaches that have been used to characterize similar mutants in the plant Rab-D2 and Rab-F2 subclasses. RAB-E1^d[NI] inhibited the transport of a secreted green fluorescent protein marker, secGFP, but in contrast with dominant-inhibitory RAB-D2 or RAB-F2 mutants, it did not affect the transport of Golgi or vacuolar markers. Quantitative imaging revealed that RAB-E1^d[NI] caused less intracellular secGFP accumulation than RAB-D2^a[NI], a dominant-inhibitory mutant of a member of the Arabidopsis Rab-D2 subclass. Furthermore, whereas RAB-D2^a[NI] caused secGFP to accumulate exclusively in the endoplasmic reticulum, RAB-E1^d[NI] caused secGFP to accumulate additionally in the Golgi apparatus and a prevacuolar compartment that could be labeled by FM4-64 and yellow fluorescent protein (YFP)–tagged Arabidopsis RAB-F2^b. Using the vacuolar protease inhibitor E64-d, it was shown that some secGFP was transported to the vacuole in control cells and in the presence of RAB-E1^d[NI]. Consistent with the hypothesis that secGFP carries a weak vacuolar-sorting determinant, it was shown that a secreted form of DsRed reaches the apoplast without appearing in the prevacuolar compartment. When fused to RAB-E1^d, YFP was targeted specifically to the Golgi via a saturable nucleotide- and prenylation-dependent mechanism but was never observed on the prevacuolar compartment. We propose that RAB-E1^d[NI] inhibits the secretory pathway at or after the Golgi, causing an accumulation of secGFP in the upstream compartments and an increase in the quantity of secGFP that enters the vacuolar pathway.

This article has been cited by other articles:

				T. Wei and A. Wang Biogenesis of Cytoplasmic Membranous Vesicles for Plant Potyvirus Replication Occurs at Endoplasmic Reticulum Exit Sites in a COPI- and COPII-Dependent Manner J. Virol., December 15, 2008; 82(24): 12252 - 12264. [Abstract] [Full Text] [PDF]

				G. Lycett The role of Rab GTPases in cell wall metabolism J. Exp. Bot., November 1, 2008; 59(15): 4061 - 4074. [Abstract] [Full Text] [PDF]

				B. Yuksel and A. R. Memon Comparative phylogenetic analysis of small GTP-binding genes of model legume plants and assessment of their roles in root nodules J. Exp. Bot., October 9, 2008; (2008) ern223v1. [Abstract] [Full Text] [PDF]

				I. Hwang Sorting and Anterograde Trafficking at the Golgi Apparatus Plant Physiology, October 1, 2008; 148(2): 673 - 683. [Full Text] [PDF]

				M. A. Held, A. Boulaflous, and F. Brandizzi Advances in Fluorescent Protein-Based Imaging for the Analysis of Plant Endomembranes Plant Physiology, August 1, 2008; 147(4): 1469 - 1481. [Full Text] [PDF]

				E. Nielsen, A. Y. Cheung, and T. Ueda The Regulatory RAB and ARF GTPases for Vesicular Trafficking Plant Physiology, August 1, 2008; 147(4): 1516 - 1526. [Full Text] [PDF]

				E. Antony, T. Taybi, M. Courbot, S. T. Mugford, J. A. C. Smith, and A. M. Borland Cloning, localization and expression analysis of vacuolar sugar transporters in the CAM plant Ananas comosus (pineapple) J. Exp. Bot., May 1, 2008; 59(7): 1895 - 1908. [Abstract] [Full Text] [PDF]

				R. U. Rehman, E. Stigliano, G. W. Lycett, L. Sticher, F. Sbano, M. Faraco, G. Dalessandro, and G.-P. Di Sansebastiano Tomato Rab11a Characterization Evidenced a Difference Between SYP121-Dependent and SYP122-Dependent exocytosis Plant Cell Physiol., May 1, 2008; 49(5): 751 - 766. [Abstract] [Full Text] [PDF]

				C.-M. Chow, H. Neto, C. Foucart, and I. Moore Rab-A2 and Rab-A3 GTPases Define a trans-Golgi Endosomal Membrane Domain in Arabidopsis That Contributes Substantially to the Cell Plate PLANT CELL, January 1, 2008; 20(1): 101 - 123. [Abstract] [Full Text] [PDF]

				P. R. Hunter, C. P. Craddock, S. Di Benedetto, L. M. Roberts, and L. Frigerio Fluorescent Reporter Proteins for the Tonoplast and the Vacuolar Lumen Identify a Single Vacuolar Compartment in Arabidopsis Cells Plant Physiology, December 1, 2007; 145(4): 1371 - 1382. [Abstract] [Full Text] [PDF]