NO regulates temperature stress in plants

Plants are affected by environmental changes, such as extreme temperature, which influences plant physiology and metabolism. Nitric oxide is a gaseous molecule that can be involved in several aspects of plant life. Heat and low temperature stresses, respectively, induces generation of nitric oxide mainly through the activity of nitrate reductase. Antioxidant machinery has an important role in the maintenance of cellular redox homeostasis. Nitric oxide regulates antioxidant enzyme activities, for example the activity of ascorbate peroxidase, through its posttranslational modifications and increase membrane stability during heat stress. Cold stress modified S-nitrosylated proteins might influence the activity of superoxide dismutase and RuBisCO. Furthermore, nitric oxide can contribute for the production of different defense molecules including heat-shock proteins. Moreover, nitric oxide may interact with different hormones, such as abscisic acid, ethylene and polyamines, through signaling molecules or by posttranslational modifications, which is also an important aspect of nitric oxide-mediated temperature stress responses.