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Title: Rapid hyperosmotic-induced Ca 2+ responses in Arabidopsis thaliana exhibit sensory potentiation and involvement of plastidial KEA transporters

Abstract

How plant roots initially sense osmotic stress in an environment of dynamic water availabilities remains largely unknown. Plants can perceive water limitation imposed by soil salinity or, potentially, by drought in the form of osmotic stress. Rapid osmotic stress-induced intracellular calcium transients provide the opportunity to dissect quantitatively the sensory mechanisms that transmit osmotic stress under environmental and genetic perturbations in plants. Here, we describe a phenomenon whereby prior exposure to osmotic stress increases the sensitivity of the rapid calcium responses to subsequent stress. Furthermore, mutations in plastidial K + exchange antiporter (KEA)1/2 and KEA3 transporters were unexpectedly found to reduce the rapid osmotic stress-induced calcium elevation. These findings advance the understanding of the mechanisms underlying the rapid osmotic stress response in plants.

Authors:
 [1];  [2];  [1];  [1]
  1. Univ. of California, San Diego, CA (United States). Food and Fuel for the 21st Century Center
  2. Univ. of California, San Diego, CA (United States). Food and Fuel for the 21st Century Center; Washington State. School of Biological Sciences
Publication Date:
Research Org.:
Univ. of California, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1411726
Grant/Contract Number:
FG02-03ER15449
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Volume: 113; Journal Issue: 35; Journal ID: ISSN 0027-8424
Publisher:
National Academy of Sciences, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; osmotic sensing; calcium; salt stress; plastid; abscisic acid

Citation Formats

Stephan, Aaron B., Kunz, Hans-Henning, Yang, Eric, and Schroeder, Julian I. Rapid hyperosmotic-induced Ca 2+ responses in Arabidopsis thaliana exhibit sensory potentiation and involvement of plastidial KEA transporters. United States: N. p., 2016. Web. doi:10.1073/pnas.1519555113.
Stephan, Aaron B., Kunz, Hans-Henning, Yang, Eric, & Schroeder, Julian I. Rapid hyperosmotic-induced Ca 2+ responses in Arabidopsis thaliana exhibit sensory potentiation and involvement of plastidial KEA transporters. United States. doi:10.1073/pnas.1519555113.
Stephan, Aaron B., Kunz, Hans-Henning, Yang, Eric, and Schroeder, Julian I. Mon . "Rapid hyperosmotic-induced Ca 2+ responses in Arabidopsis thaliana exhibit sensory potentiation and involvement of plastidial KEA transporters". United States. doi:10.1073/pnas.1519555113. https://www.osti.gov/servlets/purl/1411726.
@article{osti_1411726,
title = {Rapid hyperosmotic-induced Ca 2+ responses in Arabidopsis thaliana exhibit sensory potentiation and involvement of plastidial KEA transporters},
author = {Stephan, Aaron B. and Kunz, Hans-Henning and Yang, Eric and Schroeder, Julian I.},
abstractNote = {How plant roots initially sense osmotic stress in an environment of dynamic water availabilities remains largely unknown. Plants can perceive water limitation imposed by soil salinity or, potentially, by drought in the form of osmotic stress. Rapid osmotic stress-induced intracellular calcium transients provide the opportunity to dissect quantitatively the sensory mechanisms that transmit osmotic stress under environmental and genetic perturbations in plants. Here, we describe a phenomenon whereby prior exposure to osmotic stress increases the sensitivity of the rapid calcium responses to subsequent stress. Furthermore, mutations in plastidial K+ exchange antiporter (KEA)1/2 and KEA3 transporters were unexpectedly found to reduce the rapid osmotic stress-induced calcium elevation. These findings advance the understanding of the mechanisms underlying the rapid osmotic stress response in plants.},
doi = {10.1073/pnas.1519555113},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
number = 35,
volume = 113,
place = {United States},
year = {Mon Aug 15 00:00:00 EDT 2016},
month = {Mon Aug 15 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
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