Nitric oxide signalling in plants: interplays with Ca2+ and protein kinases

Abstract

Much attention has been paid to nitric oxide (NO) research since its discovery as a physiological mediator of plant defence responses. In recent years, newer roles have been attributed to NO, ranging from root development to stomatal closure. The molecular mechanisms underlying NO action in plants are just begun to emerge. The currently available data illustrate that NO can directly influence the activity of target proteins through nitrosylation and has the capacity to act as a Ca2+-mobilizing intracellular messenger. The interplay between NO and Ca2+ has important functional implications, expanding and enriching the possibilities for modulating transduction processes. Furthermore, protein kinases regulated through NO-dependent mechanisms are being discovered, offering fresh perspective on processes such as stress tolerance.

Signal mediators at induction of heat resistance of wheat plantlets by short-term heating

“…It is known that the plant enzyme, similar to the NO-synthase of animals, is activated with the calcium and/or calmodulin involvement [16,27]. It agrees well with the phenomenon revealed by us, which is the effect of suppression of the increase of NO content in roots, invoked by the hyperthermia, by the calcium antagonists (Fig.…”

Nitric Oxide Contributes to Cadmium Toxicity in Arabidopsis by Promoting Cadmium Accumulation in Roots and by Up-Regulating Genes Related to Iron Uptake

“…Indeed, NO was shown to promote both activation and/or inhibition of Ca 2+ influxes in plant cells exposed to biotic or abiotic stresses, highlighting its involvement in the control of Ca 2+ homeostasis (Besson-Bard et al, 2008b). Mechanistically, pharmacological studies indicate that NO affects the activity of Ca 2+ -permeable channels, but the possibility that it might also promote the activation of Ca 2+ transporters, as reported in animal cells, has been recently discussed (Courtois et al, 2008). Therefore, although the nature of the link between Cd 2+ and Ca 2+ is unresolved at present, we assume that NO might favor Cd 2+ versus Ca 2+ uptake and/or Ca 2+ extrusion partly by modulating the activity of Ca 2+ -permeable channels and/or Ca 2+ transporters.…”

“…Furthermore, NO has also been implicated in the plant adaptive response to biotic and abiotic stresses, notably by acting as a signaling molecule (Gould et al, 2003;Delledonne, 2005). It is becoming apparent that NO mediates its effects through S-nitrosylation of Cys residues of target proteins, modulation of protein kinase activities, and mobilization of free Ca 2+ and other second messengers, including cyclic GMP and cyclic ADP-Rib (Lamattina et al, 2003;Lindermayr et al, 2006;Romero-Puertas et al, 2007;Courtois et al, 2008). These processes are supposed to be a part of NO-dependent pathways leading to the activation or repression of various genes (Delledonne, 2005;Grü n et al, 2006).…”

Reactive Oxygen Species and Nitric Oxide Mediate Actin Reorganization and Programmed Cell Death in the Self-Incompatibility Response of Papaver

“…Evidence for Cross Talk between Ca 2+ , ROS, and NO in Papaver Pollen Tubes There is evidence for cross talk between [Ca 2+ ] cyt and ROS and NO in other systems (Besson-Bard et al, 2008;Courtois et al, 2008). The tip-high [Ca 2+ ] cyt gradient characteristic of tip-growing cells is closely associated with NADPH oxidase generation of ROS in pollen tubes (Potocký et al, 2007) and root hairs (Foreman et al, 2003), suggesting that [Ca 2+ ] cyt may be responsible for stimulating increases in ROS.…”