Intersection of two signalling pathways: extracellular nucleotides regulate pollen germination and pollen tube growth via nitric oxide
Open Access
- 10 April 2009
- journal article
- research article
- Published by Oxford University Press (OUP) in Journal of Experimental Botany
- Vol. 60 (7), 2129-2138
- https://doi.org/10.1093/jxb/erp091
Abstract
Plant and animal cells release or secrete ATP by various mechanisms, and this activity allows extracellular ATP to serve as a signalling molecule. Recent reports suggest that extracellular ATP induces plant responses ranging from increased cytosolic calcium to changes in auxin transport, xenobiotic resistance, pollen germination, and growth. Although calcium has been identified as a secondary messenger for the extracellular ATP signal, other parts of this signal transduction chain remain unknown. Increasing the extracellular concentration of ATPγS, a poorly-hydrolysable ATP analogue, inhibited both pollen germination and pollen tube elongation, while the addition of AMPS had no effect. Because pollen tube elongation is also sensitive to nitric oxide, this raised the possibility that a connection exists between the two pathways. Four approaches were used to test whether the germination and growth effects of extracellular ATPγS were transduced via nitric oxide. The results showed that increases in extracellular ATPγS induced increases in cellular nitric oxide, chemical agonists of the nitric oxide signalling pathway lowered the threshold of extracellular ATPγS that inhibits pollen germination, an antagonist of guanylate cyclase, which can inhibit some nitric oxide signalling pathways, blocked the ATPγS-induced inhibition of both pollen germination and pollen tube elongation, and the effects of applied ATPγS were blocked in nia1nia2 mutants, which have diminished NO production. The concurrence of these four data sets support the conclusion that the suppression of pollen germination and pollen tube elongation by extracellular nucleotides is mediated in part via the nitric oxide signalling pathway.Keywords
This publication has 55 references indexed in Scilit:
- AtNOS/AtNOA1 Is a Functional Arabidopsis thaliana cGTPase and Not a Nitric-oxide SynthasePublished by Elsevier BV ,2008
- Extracellular ATP-induced NO production and its dependence on membrane Ca2+ flux in Salvia miltiorrhiza hairy rootsJournal of Experimental Botany, 2008
- Transcriptome Analyses Show Changes in Gene Expression to Accompany Pollen Germination and Tube Growth in ArabidopsisPlant Physiology, 2008
- The Potato-Specific Apyrase Is Apoplastically Localized and Has Influence on Gene Expression, Growth, and DevelopmentPlant Physiology, 2008
- Permeation Properties of a P2X Receptor in the Green Algae Ostreococcus tauriPublished by Elsevier BV ,2008
- Extracellular ATP Induces Nitric Oxide Production in Tomato Cell SuspensionsPlant Physiology, 2007
- Apyrases (Nucleoside Triphosphate-Diphosphohydrolases) Play a Key Role in Growth Control in ArabidopsisPlant Physiology, 2007
- Extracellular ATP in Plants. Visualization, Localization, and Analysis of Physiological Significance in Growth and SignalingPlant Physiology, 2006
- Cross Talk between Reactive Nitrogen and Oxygen Species during the Hypersensitive Disease Resistance ResponsePlant Physiology, 2006
- Responses of the ciliates Tetrahymena and Paramecium to external ATP and GTPPurinergic Signalling, 2005