Plant Physiol. email content delivery
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
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 (47)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Delbarre, A.
Right arrow Articles by Guern, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Delbarre, A.
Right arrow Articles by Guern, J.
Agricola
Right arrow Articles by Delbarre, A.
Right arrow Articles by Guern, J.

PLANT PHYSIOLOGY , Vol 105, Issue 2 563-569, Copyright © 1994 by American Society of Plant Biologists

CELL BIOLOGY AND SIGNAL TRANSDUCTION

The rolB Gene of Agrobacterium rhizogenes Does Not Increase the Auxin Sensitivity of Tobacco Protoplasts by Modifying the Intracellular Auxin Concentration

A. Delbarre, P. Muller, V. Imhoff, H. Barbier-Brygoo, C. Maurel, N. Leblanc, C. Perrot-Rechenmann and J. Guern
Institut des Sciences Vegetales, Centre National de la Recherche Scientifique, F-91198 Gif-sur-Yvette Cedex, France

Phenotypical alterations observed in rolB-transformed plants have been proposed to result from a rise in intracellular free auxin due to a RolB-catalyzed hydrolysis of auxin conjugates(J.J. Estruch, J. Schell, A. Spena [1991] EMBO J 10: 3125-3128).We have investigated this hypothesis in detail using tobacco (Nicotiana tabacum) mesophyll protoplasts isolated from plants transformed with the rolB gene under the control of its own promoter (BBGUS 6 clone) or the cauliflower mosaic virus 35S promoter (CaMVBT 3 clone). Protoplasts expressing rolB showed an increased sensitivity to the auxin-induced hyperpolarization of the plasma membrane when triggered with exogenous auxin. Because this phenotypical trait was homogeneously displayed over the entire population, protoplasts were judged to be a more reliable test system than the tissue fragments used in previous studies to monitor rolB gene effects on cellular auxin levels. Accumulation of free 1-[3H]-naphthaleneacetic acid (NAA) was equivalent in CaMVBT 3, BBGUS 6, and wild-type protoplasts, Naphthyl-[beta]-glucose ester, the major NAA metabolite in protoplasts, reached similar levels in CaMVBT 3 protoplasts, reached similar levels in CaMVBT 3 and normal protoplasts and was hydrolyzed at the same rate in BBGUS 6 and normal protoplasts. Furthermore, NAA accumulation and metabolism in BBGUS 6 protoplasts were independent of the rolB gene expression level. Essentially similar results were obtained with indoleacetic acid. Thus, it was concluded that the rolB-dependent behavior of transgenic tobacco protoplasts is not a consequence of modifying the intracellular auxin concentration but likely results from changes in the auxin perception pathway.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 1994 by the American Society of Plant Biologists