A Role for the AKT1 Potassium Channel in Plant Nutrition
10.1126/science.280.5365.918
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

In plants, potassium serves an essential role as an osmoticum and charge carrier. Its uptake by roots occurs by poorly defined mechanisms. To determine the role of potassium channels in planta, we performed a reverse genetic screen and identified an Arabidopsis thaliana mutant in which the AKT1 channel gene was disrupted. Roots of this mutant lacked inward-rectifying potassium channels and displayed reduced potassium (rubidium-86) uptake. Compared with wild type, mutant plants grew poorly on media with a potassium concentration of 100 micromolar or less. These results and membrane potential measurements suggest that the AKT1 channel mediates potassium uptake from solutions that contain as little as 10 micromolar potassium.

Bibliography

Hirsch, R. E., Lewis, B. D., Spalding, E. P., & Sussman, M. R. (1998). A Role for the AKT1 Potassium Channel in Plant Nutrition. Science, 280(5365), 918–921.

Authors 4
  1. Rebecca E. Hirsch (first)
  2. Bryan D. Lewis (additional)
  3. Edgar P. Spalding (additional)
  4. Michael R. Sussman (additional)
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  25. Supported by the Department of Energy (DOE)/NSF/USDA Collaborative Research in Plant Biology Program (BIR-9220331) funds to R.E.H. from the NIH University of Wisconsin Cellular and Molecular Biology Training Grant (GM07215) to M.R.S. from DOE (DE-FG02-88ER13938) and NSF (DCB-90-04068) and to E.P.S. from the NASA/NSF Network for Research on Plant Sensory Systems (IBN-9416016). We thank T. Janczewski and R. Meister for technical assistance and P. Krysan W. Robertson J. Satterlee and J. Young for helpful comments on the manuscript.
Dates
Type When
Created 23 years ago (July 27, 2002, 5:42 a.m.)
Deposited 1 year, 7 months ago (Jan. 12, 2024, 10:35 p.m.)
Indexed 2 weeks, 4 days ago (Aug. 7, 2025, 4:52 a.m.)
Issued 27 years, 3 months ago (May 8, 1998)
Published 27 years, 3 months ago (May 8, 1998)
Published Print 27 years, 3 months ago (May 8, 1998)
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@article{Hirsch_1998, title={A Role for the AKT1 Potassium Channel in Plant Nutrition}, volume={280}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.280.5365.918}, DOI={10.1126/science.280.5365.918}, number={5365}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Hirsch, Rebecca E. and Lewis, Bryan D. and Spalding, Edgar P. and Sussman, Michael R.}, year={1998}, month=may, pages={918–921} }