Hydrogen peroxide is a common signal for darkness- and ABA-induced stomatal closure in Pisum sativum

• DOI: 10.1071/fp04035
• Publication Date: 2004-12-22T00:56:07Z
• Authors: Radhika Desikan; Man-Kim Cheung; Andrew Clarke; Sarah Golding; Moshe Sagi; Robert Fluhr; Christopher Rock; John Hancock; Steven Neill
• Keywords: Darkness

The requirement for hydrogen peroxide (H2O2) generation and action during stomatal closure induced by darkness abscisic acid (ABA) was investigated in pea (Pisum sativum L.). Stomatal or ABA inhibited the H2O2-scavenging enzyme catalase antioxidant N-acetyl cysteine (NAC), diphenylene iodonium (DPI), an inhibitor of H2O2-generating NADPH oxidase. Exogenous H2O2 a dose- time-dependent manner, also required ABA-inhibition opening light. accumulation guard cells increased ABA, as assessed with fluorescent dye dichlorodihydrofluorescein diacetate (H2-DCFDA) confocal microscopy. Such increases were catalase, NAC DPI, consistent effects these compounds on apertures. Employing polymerase chain reaction (PCR) degenerate oligonucleotide primers, several oxidase homologues identified from genomic DNA that had substantial identity to Arabidopsis thaliana (L.) Heynh. rboh (respiratory burst homologue) genes. Furthermore, antibody raised against tomato immunoreactive proteins epidermal, mesophyll cells.