Hypertonic Stress Increased Extracellular ATP Levels and the Expression of Stress-Responsive Genes inArabidopsis thalianaSeedlings

Receptor-Like Activity Evoked by Extracellular ADP in Arabidopsis Root Epidermal Plasma Membrane

“…Extracellular purine nucleotides have been shown to be involved in the regulation of plant cell viability, membrane permeability, immunity, symbiosis, stress responses, and growth (Lew and Dearnaley, 2000;Tang et al, 2003;Chivasa et al, 2005Chivasa et al, , 2009Kim et al, 2006Kim et al, , 2009Roux and Steinebrunner, 2007;Wu et al, 2007;Riewe et al, 2008a;Wu and Wu, 2008;Yi et al, 2008;Demidchik et al, 2009;Govindarajulu et al, 2009;Kim et al, 2009;Clark et al, 2010aClark et al, , 2010bTanaka et al, 2010aTanaka et al, , 2010bTerrile et al, 2010;Tonó n et al, 2010). Purine nucleotide release from plant cells may occur through wounding, exocytosis, or through the activity of plasma membrane (PM) ATP-binding cassette transporters (Thomas et al, 2000;Kim et al, 2006).…”

“…Manipulation of ecto-apyrase levels results in abnormal growth in Arabidopsis (Arabidopsis thaliana), cotton (Gossypium hirsutum), and potato (Solanum tuberosum; Wu et al, 2007;Riewe et al, 2008a;Clark et al, 2010aClark et al, , 2010b while nodulation by Bradyrhizobium japonicum is impaired in ecto-apyrase-deficient soybean (Glycine max; Govindarajulu et al, 2009). Current models suggest that poise of the cell's state between death, stress adaptation, and growth involves signaling governed by the level of extracellular ATP (Chivasa et al, 2005Roux and Steinebrunner, 2007;Wu et al, 2007;Wu and Wu, 2008;Kim et al, 2009;Clark et al, 2010aClark et al, , 2010bTerrile et al, 2010;Tonó n et al, 2010).…”

Extracellular ATP signaling and homeostasis in plant cells

“…In Arabidopsis, hypertonic stress induced an obvious elevation of [eATP] and is accompanied by an increased expression of APY1 and APY2. 8,9 Similarly, we found that the transcripts of PeAPY1 and PeAPY2 in cell cultures of P. euphratica were upregulated by a various abiotic stresses (Sun J., Deng S. and Chen S., unpublished data). These data reveal that apyrases, which contribute to eATP homeostasis, play an important role in regulating the plant adaptations to environmental stress.…”

“…[1][2][3][4][5] In plant cells, intracellular ATP, which is in the mM range, can be released into extracellular matrix (ECM) under various environmental conditions, such as wounding, 6 mechanical stimulation, 7 hypertonic and hypotonic shock. 8,9 The release of ATP is usually through anion channels, 10 protein transporters 11 and exocytosis of ATPenriched vesicles. 12 In animals, eATP is sensed by the plasma membrane purinergic receptors, including ligand-gated ion channels (P2X) and G protein-coupled receptors (P2Y), and then triggers downstream physiological responses.…”

Release of extracellular purines from plant roots and effect on ion fluxes

“…16 ATP is released at plant wound and growth points, in response to touch, elicitors and hyperosmotic stress imposed by salts. 1,17,18 Here, wounding, hyperosmotic or sodicity stress resulted in distinct levels and time courses of ATP accumulation around excised roots of A. thaliana ( Fig. 1).…”