OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) Supplemental Data OA All Versions of this Article: 147/4/1646    most recent pp.108.120212v2 pp.108.120212v1 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 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 Web of Science (12) Citing Articles via Google Scholar Google Scholar Articles by Bove, J. Articles by Geitmann, A. Search for Related Content PubMed PubMed Citation Articles by Bove, J. Articles by Geitmann, A. Agricola Articles by Bove, J. Articles by Geitmann, A. Related Collections Membrane Trafficking

Magnitude and Direction of Vesicle Dynamics in Growing Pollen Tubes Using Spatiotemporal Image Correlation Spectroscopy and Fluorescence Recovery after Photobleaching^1,[W],[OA]

Institut de recherche en biologie végétale, Département de sciences biologiques, Université de Montréal, Montreal, Quebec, Canada H1X 2B2 (J.B., A.G.); Department of Physics, McGill University, Montreal, Quebec, Canada H3A 2T8 (B.V., J.K., P.W.W.); Biology Department, University of Massachusetts, Amherst, Massachusetts 01003 (P.K.H.); and Department of Chemistry, McGill University, Montreal, Quebec, Canada H3A 2K6 (P.W.W.)

The delivery of cell wall material and membrane to growing plant cell surfaces requires the spatial and temporal coordination of secretory vesicle trafficking. Given the small size of vesicles, their dynamics is difficult to quantify. To quantitatively analyze vesicle dynamics in growing pollen tubes labeled with the styryl dye FM1-43, we applied spatiotemporal correlation spectroscopy on time-lapse series obtained with high-speed confocal laser scanning microscopy recordings. The resulting vector maps revealed that vesicles migrate toward the apex in the cell cortex and that they accumulate in an annulus-shaped region adjacent to the extreme tip and then turn back to flow rearward in the center of the tube. Fluorescence recovery after photobleaching confirmed vesicle accumulation in the shoulder of the apex, and it revealed that the extreme apex never recovers full fluorescence intensity. This is consistent with endocytotic activity occurring in this region. Fluorescence recovery after photobleaching analysis also allowed us to measure the turnover rate of the apical vesicle population, which was significantly more rapid than the theoretical rate computed based on requirements for new cell wall material. This may indicate that a significant portion of the vesicles delivered to the apex does not succeed in contacting the plasma membrane for delivery of their contents. Therefore, we propose that more than one passage into the apex may be needed for many vesicles before they fuse to the plasma membrane and deliver their contents.

The authors responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) are: Anja Geitmann (anja.geitmann{at}umontreal.ca) and Paul W. Wiseman (paul.wiseman{at}mcgill.ca; STICS software).

^[W] The online version of this article contains Web-only data.

^[OA] Open Access articles can be viewed online without a subscription.

www.plantphysiol.org/cgi/doi/10.1104/pp.108.120212

^* Corresponding author; e-mail anja.geitmann{at}umontreal.ca.

Received April 1, 2008; accepted May 19, 2008; published May 28, 2008.

This article has been cited by other articles:

				S. Wolf, G. Mouille, and J. Pelloux Homogalacturonan Methyl-Esterification and Plant Development Mol Plant, September 1, 2009; 2(5): 851 - 860. [Abstract] [Full Text] [PDF]

				M. Iwano, T. Entani, H. Shiba, M. Kakita, T. Nagai, H. Mizuno, A. Miyawaki, T. Shoji, K. Kubo, A. Isogai, et al. Fine-Tuning of the Cytoplasmic Ca2+ Concentration Is Essential for Pollen Tube Growth Plant Physiology, July 1, 2009; 150(3): 1322 - 1334. [Abstract] [Full Text] [PDF]

				G. Cai and M. Cresti Organelle motility in the pollen tube: a tale of 20 years J. Exp. Bot., February 1, 2009; 60(2): 495 - 508. [Abstract] [Full Text] [PDF]

				C. B. Lee, S. Kim, and B. McClure A Pollen Protein, NaPCCP, That Binds Pistil Arabinogalactan Proteins Also Binds Phosphatidylinositol 3-Phosphate and Associates with the Pollen Tube Endomembrane System Plant Physiology, February 1, 2009; 149(2): 791 - 802. [Abstract] [Full Text] [PDF]

				A. Y. Cheung and S. C. de Vries Membrane Trafficking: Intracellular Highways and Country Roads Plant Physiology, August 1, 2008; 147(4): 1451 - 1453. [Full Text] [PDF]