NADPH oxidase-dependent hydrogen peroxide production, induced by salinity stress, may be involved in the regulation of total calcium in roots of wheat

Salinity-Induced Calcium Signaling and Root Adaptation in Arabidopsis Require the Calcium Regulatory Protein Annexin1

“…This is consistent with our finding (using patch clamping) that AtANN1 is a necessary component of the epidermal plasma membrane Ca 2+ influx conductance activated by NaCl and known from a previous study to require NADPH oxidase activity (Ma et al, 2012). We envisage that as NADPH oxidase activity and extracellular OH c production by roots increase under high salinity stress (Yang et al, 2007;Demidchik et al, 2010;Kaye et al, 2011;Xie et al, 2011;Liu et al, 2012;Ma et al, 2012), AtANN1 fulfills its previously defined role of mediating the root epidermal plasma membrane Ca 2+ influx conductance that is activated by extracellular OH c (Laohavisit et al, 2012). The currentvoltage relationship of recombinant AtANN1 in vitro suggests that AtANN1's contribution to Ca 2+ influx across the plasma membrane would decline if membrane voltage depolarized, for example through increased soil [K + ].…”

“…On exposure to extracellular NaCl, plasma membrane NADPH oxidases are activated to produce extracellular superoxide anion (Yang et al, 2007;Chung et al, 2008;Kaye et al, 2011;Xie et al, 2011;Jiang et al, 2012;Liu et al, 2012;Ma et al, 2012). This drives production of extracellular OH c , with up to a 5-fold increase in [OH c ] detected in NaCl-stressed Arabidopsis roots (Demidchik et al, 2010).…”

NADPH Oxidase-Mediated Redox Signaling: Roles in Cellular Stress Response, Stress Tolerance, and Tissue Repair

“…It is noteworthy that some studies have indicated that there might be a feed-forward mechanism in regulation of the Nox5 function by calcium in plant cells. Evidence has shown that, apart from the Ca 2ϩ -dependent Nox activation, Nox-derived ROS can in turn promote Ca 2ϩ entry into the cells (Foreman et al, 2003;Mori and Schroeder, 2004;Yang et al, 2007b). Animal Nox5 is found in fetal tissues, T and B lymphocytes, and sperm precursors in testis .…”

Plant Plasma Membrane H+-ATPase in Adaptation of Plants to Abiotic Stresses

“…Nitric oxide (NO) and hydrogen peroxide (H 2 O 2 ) function as signal molecules in plants subjected to abiotic stresses. In plants, the generation of H 2 O 2 seems to be mediated by a plasma membrane bound NADPH oxidase complex (Yang et al, 2007;Lherminier et al, 2009). NO is synthesized via nitric oxide synthase (NOS) and nitrate reductase (Yamasaki & Sakihama, 2000).…”