Abstract
Nitric oxide (NO) is a ubiquitous signaling molecule involved in diverse physiological process. Despite the wealth of information gathered over the last decade, the mechanisms of NO action are poorly known. We now assess the possibility that nitrated cGMP (8-nitro-cGMP) functions in guard cell signaling. At previous meeting, we reported that 8-nitro-cGMP is formed in an NO- and reactive oxygen species(ROS)-dependent manner and nitrated cGMP induce stomatal closure. At this meeting, we studied sorce of ROS to trigger the nitration of cGMP occur in guard cells, Immunocytochemical analyses were performed using a monoclonal antibody against 8-nitro-cGMP. The mitochondrial respiration cyclase inhibitor, photosynthesis inhibitor and the darek cause decrease of ABA-induced immunofluorescence. These results indicate that mitochondrial respiration and photosynthesis are the source of ROS-cGMP to form 8-nitro-cGMP.
