Extracellular nucleotides elicit cytosolic free calcium oscillations in Arabidopsis

Kiwamu Tanaka; Sarah J Swanson; Simon Gilroy; Gary Stacey

doi:10.1104/pp.110.162503

Back

Extracellular nucleotides elicit cytosolic free calcium oscillations in Arabidopsis

Journal article

Open access

Extracellular nucleotides elicit cytosolic free calcium oscillations in Arabidopsis

Kiwamu Tanaka, Sarah J Swanson, Simon Gilroy and Gary Stacey

Plant physiology (Bethesda), Vol.154(2), pp.705-719

10/2010

DOI: https://doi.org/10.1104/pp.110.162503

Handle:

https://hdl.handle.net/2376/115945

PMID: 20671112

Files and links (1)

url

https://doi.org/10.1104/pp.110.162503View

Published (Version of record) Open

Abstract

Calcium-Binding Proteins - metabolism

Arabidopsis - drug effects

Plants, Genetically Modified - genetics

Seedlings - genetics

Heterotrimeric GTP-Binding Proteins - metabolism

Seedlings - drug effects

Calcium Channel Blockers - pharmacology

Heterotrimeric GTP-Binding Proteins - genetics

Arabidopsis - metabolism

Arabidopsis - genetics

Aequorin - metabolism

Plants, Genetically Modified - metabolism

Calcium Signaling - drug effects

Nucleotides - pharmacology

Fluorescence Resonance Energy Transfer

Mutation

Seedlings - metabolism

Extracellular ATP induces a rise in the level of cytosolic free calcium ([Ca(2+)](cyt)) in plant cells. To expand our knowledge about the function of extracellular nucleotides in plants, the effects of several nucleotide analogs and pharmacological agents on [Ca(2+)](cyt) changes were studied using transgenic Arabidopsis (Arabidopsis thaliana) expressing aequorin or the fluorescence resonance energy transfer-based Ca(2+) sensor Yellow Cameleon 3.6. Exogenously applied CTP caused elevations in [Ca(2+)](cyt) that displayed distinct time- and dose-dependent kinetics compared with the purine nucleotides ATP and GTP. The inhibitory effects of antagonists of mammalian P2 receptors and calcium influx inhibitors on nucleotide-induced [Ca(2+)](cyt) elevations were distinct between CTP and purine nucleotides. These results suggest that distinct recognition systems may exist for the respective types of nucleotides. Interestingly, a mutant lacking the heterotrimeric G protein Gβ-subunit exhibited a remarkably higher [Ca(2+)](cyt) elevation in response to all tested nucleotides in comparison with the wild type. These data suggest a role for Gβ in negatively regulating extracellular nucleotide signaling and point to an important role for heterotrimeric G proteins in modulating the cellular effects of extracellular nucleotides. The addition of extracellular nucleotides induced multiple temporal [Ca(2+)](cyt) oscillations, which could be localized to specific root cells. The oscillations were attenuated by a vesicle-trafficking inhibitor, indicating that the oscillations likely require ATP release via exocytotic secretion. The results reveal new molecular details concerning extracellular nucleotide signaling in plants and the importance of fine control of extracellular nucleotide levels to mediate specific plant cell responses.

Metrics

10 Record Views

Details

Title: Extracellular nucleotides elicit cytosolic free calcium oscillations in Arabidopsis
Creators: Kiwamu Tanaka - National Center for Soybean Biotechnology, Division of Plant Sciences, University of Missouri, Columbia, Missouri 65211, USA
Sarah J Swanson
Simon Gilroy
Gary Stacey
Publication Details: Plant physiology (Bethesda), Vol.154(2), pp.705-719
Academic Unit: Plant Pathology, Department of
Publisher: United States
Identifiers: 99900547885001842
Language: English
Resource Type: Journal article