This Article Full Text (PDF) 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 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 Google Scholar Google Scholar Articles by Lefebvre, D. D. Articles by Plaxton, W. C. Search for Related Content PubMed PubMed Citation Articles by Lefebvre, D. D. Articles by Plaxton, W. C. Agricola Articles by Lefebvre, D. D. Articles by Plaxton, W. C.

Environmental and Stress Physiology

Response to Phosphate Deprivation in Brassica nigra Suspension Cells ¹

Enhancement of Intracellular, Cell Surface, and Secreted Phosphatase Activities Compared to Increases in Pi-Absorption Rate

Department of Biology, Queen's University, Kingston, Ontario K7L 3N6 Canada

Suspension cells of Brassica nigra responded to Pi deprivation by increasing their potential for Pi influx and by raising the active levels of intracellular, cell surface, and secreted acid phosphatases. These responses, however, were temporally distinct. Phosphate influx capacity increased 15-fold in parallel to a 10-fold decrease in endogenous Pi during 7 days of culture in basal growth medium. In contrast, intracellular and cell surface phosphatase activities changed only after alterations in cellular phosphorus status had been in place for a number of days. Even in nutrient sufficient cells the secretion of phosphatase remained relatively high as did the activities of the other phosphatases. The cell surface acid phosphatase had a K_m of approximately 10 times that of the influx process and molybdate was a much stronger inhibitor of this phosphatase activity. From these results it appears that Pi absorption and the production or activation of phosphatases are regulated in a distinct manner. In addition, Pi uptake into Brassica nigra cells does not appear to directly involve the cell surface phosphatase under Pi-deficient conditions.

This article has been cited by other articles:

				S. Alvarez, Y. He, and S. Chen Comparative Investigations of the Glucosinolate-Myrosinase System in Arabidopsis Suspension Cells and Hypocotyls Plant Cell Physiol., March 1, 2008; 49(3): 324 - 333. [Abstract] [Full Text] [PDF]

				V. Veljanovski, B. Vanderbeld, V. L. Knowles, W. A. Snedden, and W. C. Plaxton Biochemical and Molecular Characterization of AtPAP26, a Vacuolar Purple Acid Phosphatase Up-Regulated in Phosphate-Deprived Arabidopsis Suspension Cells and Seedlings Plant Physiology, November 1, 2006; 142(3): 1282 - 1293. [Abstract] [Full Text] [PDF]

				C.-W. Chang, J. L. Moseley, D. Wykoff, and A. R. Grossman The LPB1 Gene Is Important for Acclimation of Chlamydomonas reinhardtii to Phosphorus and Sulfur Deprivation Plant Physiology, May 1, 2005; 138(1): 319 - 329. [Abstract] [Full Text] [PDF]

				S. M. LI, L. LI, F. S. ZHANG, and C. TANG Acid Phosphatase Role in Chickpea/Maize Intercropping Ann. Bot., August 1, 2004; 94(2): 297 - 303. [Abstract] [Full Text] [PDF]

				K. Shimogawara, D. D. Wykoff, H. Usuda, and A. R. Grossman Chlamydomonas reinhardtii Mutants Abnormal in Their Responses to Phosphorus Deprivation Plant Physiology, July 1, 1999; 120(3): 685 - 694. [Abstract] [Full Text]

				S. H. Burleigh and M. J. Harrison The Down-Regulation of Mt4-Like Genes by Phosphate Fertilization Occurs Systemically and Involves Phosphate Translocation to the Shoots Plant Physiology, January 1, 1999; 119(1): 241 - 248. [Abstract] [Full Text]