[Seed dormancy alleviation and oxidative signaling].

Recent advances in plant physiology signaling pathways have led to consider reactive oxygen species (ROS) as being key actors in the regulation of germination and dormancy. ROS accumulation during seed dry storage or during their imbibition would trigger cellular events controlling the realization of germination. We show that ROS accumulation triggers specific carbonylation of proteins thus modifying the occurrence of enzyme-mediated reactions during germination or facilitating reserve protein degradation through the proteasome. This suggests that dormancy is in part controlled by protein oxidation. ROS can also act as a positive signal in seed dormancy release through their effect on other mechanisms such as the control of the cellular redox status and the activation of transcription factors. Their interaction with abscisic acid and gibberellins is also evoked and a new mechanism of dormancy regulation in which ROS crosstalk with hormonal pathways is proposed.