Skip Navigation


JXB Advance Access originally published online on August 28, 2007
Journal of Experimental Botany 2007 58(11):3005-3015; doi:10.1093/jxb/erm155
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrowOA All Versions of this Article:
58/11/3005    most recent
erm155v1
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
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 arrow Disclaimer
Google Scholar
Right arrow Articles by Kramer, E. M.
Right arrow Articles by Baskin, T. I.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kramer, E. M.
Right arrow Articles by Baskin, T. I.
Agricola
Right arrow Articles by Kramer, E. M.
Right arrow Articles by Baskin, T. I.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2007 The Author(s).
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. This paper is available online free of all access charges (see http://jxb.oxfordjournals.org/open_access.html for further details)

RESEARCH PAPER

Measurement of diffusion within the cell wall in living roots of Arabidopsis thaliana

Eric M. Kramer1,2,*, Nicholas L. Frazer2 and Tobias I. Baskin1

1Biology Department, University of Massachusetts, 611 N. Pleasant St, Amherst, MA 01003, USA
2Physics Department, Simon's Rock College, Great Barrington, MA 01230, USA

* To whom correspondence should be addressed. E-mail: ekramer{at}simons-rock.edu

To quantify the diffusion constant of small molecules in the plant cell wall, fluorescence from carboxyfluorescein (CF) in the intact roots of Arabidopsis thaliana was recorded. Roots were immersed in a solution of the fluorescent dye and viewed through a confocal fluorescence microscope. These roots are sufficiently transparent that much of the apoplast can be imaged. The diffusion coefficient, Dcw, of CF in the cell wall was probed using two protocols: fluorescence recovery after photobleaching and fluorescence loss following perfusion with dye-free solution. Diffusion coefficients were obtained from the kinetics of the fluorescent transients and modelling apoplast geometry. Apoplastic diffusion constants varied spatially in the root. In the elongation zone and mature cortex, Dcw=(3.2±1.4)x10–11 m2 s–1, whereas in mature epidermis, Dcw=(2.5±0.7)x10–12 m2 s–1, at least an order of magnitude lower. Relative to the diffusion coefficient of CF in water, these represent reductions by approximately 1/15 and 1/195, respectively. The low value for mature epidermis is correlated with a suberin-like permeability barrier that was detected with either autofluorescence or berberine staining. This study provides a quantitative estimate of the permeability of plant cell walls to small organic acids—a class of compounds that includes auxin and other plant hormones. These measurements constrain models of solute transport, and are important for quantitative models of hormone signalling during plant growth and development.

Key words: Apoplast, Arabidopsis, carboxyfluorescein, cell wall, diffusion

Received 31 January 2006; Revised 13 May 2007 Accepted 11 June 2007


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Proc. Natl. Acad. Sci. USAHome page
S. Hoth, R. Stadler, N. Sauer, and U. Z. Hammes
Differential vascularization of nematode-induced feeding sites
PNAS, August 26, 2008; 105(34): 12617 - 12622.
[Abstract] [Full Text] [PDF]


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.