Plant Physiol. Illumina
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Physiology Preview
Published on March 6, 2009; 10.1104/pp.109.137083

This Article
Right arrow Full Text (Plant Physiology Preview (PDF))
Right arrow All Versions of this Article:
150/1/96    most recent
pp.109.137083v1
Right arrow Alert me when this article is cited
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 Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Web of Science (2)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Christensen, N. M.
Right arrow Articles by Oparka, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Christensen, N. M.
Right arrow Articles by Oparka, K.
Agricola
Right arrow Articles by Christensen, N. M.
Right arrow Articles by Oparka, K.

Received February 18, 2009
Accepted March 1, 2009

Evidence for unidirectional flow through plasmodesmata

Nynne Meyn Christensen , Christine Faulkner , and Karl Oparka *

Institute of Molecular Plant Sciences, University of Edinburgh Mayfield Road, Edinburgh EH9 3JR, UK

* Corresponding author; email: Karl.Oparka{at}ed.ac.uk.

The leaf trichome of Nicotiana tabacum represents a unique secretory structure in which the basal trichome cell is connected to the epidermis by numerous plasmodesmata (PD). Small fluorescent probes microinjected into the basal trichome cell moved apically into distal trichome cells but not into the subtending epidermal cell. In marked contrast, the same probes moved apically into trichome cells when injected into the epidermal cell. Non-invasive methods of dye loading, including ester loading into the apical secretory cell by trichome ‘capping’, and by infiltration of caged fluorescein, produced the same result. In transgenic tobacco plants constitutively expressing photoactivatable GFP (PAGFP), activation of PAGFP above the epidermal/trichome (e/t) boundary resulted in movement of protein apically into the distal trichome cells but not across the e/t boundary, while PAGFP activated in the epidermal cell moved apically across the e/t boundary. Experiments with apoplastic tracers also revealed the presence of a distinct apoplastic barrier to solute movement at the e/t interface. These data point to unidirectional transport of solutes through PD. PAGFP activated in individual cells equidistant between the basal cell and the apical cell moved bidirectionally from these cells, suggesting that mass flow was not the driving force for unidirectional transport. We found that unidirectional transport across the e/t boundary was not affected by virus infection or by addition of the actin inhibitor latrunclulin, but could be dissipated completely by addition of sodium azide. Collectively, our data suggest that active, unidirectional transport of molecules may occur through plasmodesmata located at unique interfaces in the plant.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 2009 by the American Society of Plant Biologists