G Protein Regulation of Ion Channels and Abscisic Acid Signaling in Arabidopsis Guard Cells
10.1126/science.1059046
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The phytohormone abscisic acid (ABA) promotes plant water conservation by decreasing the apertures of stomatal pores in the epidermis through which water loss occurs. We found that Arabidopsis thaliana plants harboring transferred DNA insertional mutations in the sole prototypical heterotrimeric GTP-binding (G) protein α subunit gene, GPA1 , lack both ABA inhibition of guard cell inward K + channels and pH-independent ABA activation of anion channels. Stomatal opening in gpa1 plants is insensitive to inhibition by ABA, and the rate of water loss from gpa1 mutants is greater than that from wild-type plants. Manipulation of G protein status in guard cells may provide a mechanism for controlling plant water balance.

Bibliography

Wang, X.-Q., Ullah, H., Jones, A. M., & Assmann, S. M. (2001). G Protein Regulation of Ion Channels and Abscisic Acid Signaling in Arabidopsis Guard Cells. Science, 292(5524), 2070–2072.

Authors 4
  1. Xi-Qing Wang (first)
  2. Hemayet Ullah (additional)
  3. Alan M. Jones (additional)
  4. Sarah M. Assmann (additional)
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  49. Supported by USDA grants 98-35304-6681 and 2001-35304-09916 and NSF grant MCB-9874438 to S.M.A. We thank Z.-M. Pei for advice on patch-clamping Arabidopsis guard cells.
Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:52 a.m.)
Deposited 1 year, 7 months ago (Jan. 9, 2024, 5:28 p.m.)
Indexed 1 week, 1 day ago (Aug. 29, 2025, 6:26 a.m.)
Issued 24 years, 2 months ago (June 15, 2001)
Published 24 years, 2 months ago (June 15, 2001)
Published Print 24 years, 2 months ago (June 15, 2001)
Funders 0

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@article{Wang_2001, title={G Protein Regulation of Ion Channels and Abscisic Acid Signaling in Arabidopsis Guard Cells}, volume={292}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.1059046}, DOI={10.1126/science.1059046}, number={5524}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Wang, Xi-Qing and Ullah, Hemayet and Jones, Alan M. and Assmann, Sarah M.}, year={2001}, month=jun, pages={2070–2072} }