Abstract:

Sodium stimulated ATPase activity in the nuclei of the meristematic cells, while potassium stimulated it in the mycorrhizae between root cap cells. The detection of these 2 mutually exclusive cation-stimulated ATPases, which both require magnesium-ATP in equivalents, which have a similar optimum pH of about 5.5, and which are located in entirely different parts of the root tip, suggests that particular enzyme systems can only be activated by a specific cation and that one cation cannot substitute for the other. Such a feature may explain the capacity of plants to differentiate between ions as closely similar as sodium and potassium. The similarities between the enzyme system described for salt transport in animal tissues and that depicted here cytochemically in pine roots at the most active site of salt uptake in roots indicate this may be a carrier mechanism for salt entry into plant roots. The presence of the potassium-activated enzyme only in the mycorrhizae may relate to the dependence of pine trees on mycorrhizae for growth.

Open in

PUBMED | PMC | Google Scholar | Wikipedia

Relations:

Content

Citations

(6)

References

(10)

Drugs

(1)

Affiliates

(1)

Cytochemical Demonstration of a Sodium-Activated and a Potassium-Activated Adenosine Triphosphatase in Loblolly Pine Seedling Root Tips

I McClurkin

D McClurkin

Abstract

Sodium stimulated ATPase activity in the nuclei of the meristematic cells, while potassium stimulated it in the mycorrhizae between root cap cells. The detection of these 2 mutually exclusive cation-stimulated ATPases, which both require magnesium-ATP in equivalents, which have a similar optimum pH of about 5.5, and which are located in entirely different parts of the root tip, suggests that particular enzyme systems can only be activated by a specific cation and that one cation cannot substitute for the other. Such a feature may explain the capacity of plants to differentiate between ions as closely similar as sodium and potassium. The similarities between the enzyme system described for salt transport in animal tissues and that depicted here cytochemically in pine roots at the most active site of salt uptake in roots indicate this may be a carrier mechanism for salt entry into plant roots. The presence of the potassium-activated enzyme only in the mycorrhizae may relate to the dependence of pine trees on mycorrhizae for growth.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.6M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Images in this article

Image
on p.1105

Image
on p.1107

Click on the image to see a larger version.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

BERG GG. THE STAINING OF TRIPHOSPHATASES BY THE CHELATE REMOVAL METHOD. J Histochem Cytochem. 1964 May;12:341–358. [PubMed] [Google Scholar]
HENDRICKS SB. SALT TRANSPORT ACROSS CELL MEMBRANES. Am Sci. 1964 Sep;52:306–333. [PubMed] [Google Scholar]
MCCLURKIN IT. A METHOD FOR THE CYTOCHEMICAL DEMONSTRATION OF SODIUM-ACTIVATED ADENOSINE TRIPHOSPHATASE. J Histochem Cytochem. 1964 Sep;12:654–658. [PubMed] [Google Scholar]
NOVIKOFF AB, DRUCKER J, SHIN WY, GOLDFISCHER S. Further studies of the apparent adenosinetriphosphatase activity of cell membranes in formol-calcium-fixed tissues. J Histochem Cytochem. 1961 Jul;9:434–451. [PubMed] [Google Scholar]
NOVIKOFF AB, GOLDFISCHER S, ESSNER E. The importance of fixation in a cytochemical method for the Golgi apparatus. J Histochem Cytochem. 1961 Jul;9:459–460. [PubMed] [Google Scholar]
Rains DW, Epstein E. Transport of Sodium in Plant Tissue. Science. 1965 Jun 18;148(3677):1611–1611. [PubMed] [Google Scholar]
SKOU JC. The influence of some cations on an adenosine triphosphatase from peripheral nerves. Biochim Biophys Acta. 1957 Feb;23(2):394–401. [PubMed] [Google Scholar]
SKOU JC. ENZYMATIC BASIS FOR ACTIVE TRANSPORT OF NA+ AND K+ ACROSS CELL MEMBRANE. Physiol Rev. 1965 Jul;45:596–617. [PubMed] [Google Scholar]
WACHSTEIN M, MEISEL E. Histochemistry of hepatic phosphatases of a physiologic pH; with special reference to the demonstration of bile canaliculi. Am J Clin Pathol. 1957 Jan;27(1):13–23. [PubMed] [Google Scholar]
WHITTAM R, WHEELER KP. The sensitivity of a kidney ATPase to ouabain and to sodium and potassium. Biochim Biophys Acta. 1961 Aug 19;51:622–624. [PubMed] [Google Scholar]

Department of Biology, University of Mississippi, University, Mississippi 38677

Southern Forest Experiment Station, Forest Service, United States Department of Agriculture, Oxford, Mississippi 38655

Copyright notice

Abstract

Sodium stimulated ATPase activity in the nuclei of the meristematic cells, while potassium stimulated it in the mycorrhizae between root cap cells. The detection of these 2 mutually exclusive cation-stimulated ATPases, which both require magnesium-ATP in equivalents, which have a similar optimum pH of about 5.5, and which are located in entirely different parts of the root tip, suggests that particular enzyme systems can only be activated by a specific cation and that one cation cannot substitute for the other. Such a feature may explain the capacity of plants to differentiate between ions as closely similar as sodium and potassium. The similarities between the enzyme system described for salt transport in animal tissues and that depicted here cytochemically in pine roots at the most active site of salt uptake in roots indicate this may be a carrier mechanism for salt entry into plant roots. The presence of the potassium-activated enzyme only in the mycorrhizae may relate to the dependence of pine trees on mycorrhizae for growth.

Collaboration tool especially designed for Life Science professionals.Drag-and-drop any entity to your messages.

Learn More