Action and target sites of nitric oxide in chloroplasts

• Target sites of nitric oxide action in chloroplasts.
• Nitric oxide-induced changes in the photosynthetic apparatus.
• Role of nitric oxide for increased stability of PSII under stress.

Nitric oxide (NO) is an important signalling molecule in plants under physiological and stress conditions. Here we review the influence of NO on chloroplasts which can be directly induced by interaction with the photosynthetic apparatus by influencing photophosphorylation, electron transport activity and oxido-reduction state of the Mn clusters of the oxygen-evolving complex or by changes in gene expression. The influence of NO-induced changes in the photosynthetic apparatus on its functions and sensitivity to stress factors are discussed.