Nitric oxide is induced by wounding and influences jasmonic acid signaling in Arabidopsis thaliana

Abstract

Nitric oxide (NO) has been associated with plant defense responses during microbial attack, and with induction and/or regulation of programmed cell death. Here, we addressed whether NO participates in wound responses in Arabidopsis thaliana (L.) Heynh. Real-time imaging by confocal laser-scanning microscopy in conjunction with the NO-selective fluorescence indicator 4,5-diaminofluorescein diacetate (DAF-2 DA) uncovered a strong NO burst after wounding or after treatment with JA. The NO burst was triggered within minutes, reminiscent of the oxidative burst during hypersensitive responses. Furthermore, we were able to detect NO in plants (here induced by wounding) by means of electron paramagnetic resonance measurements using diethyldithiocarbamate as a spin trap. When plants were treated with NO, Northern analyses revealed that NO strongly induces key enzymes of jasmonic acid (JA) biosynthesis such as allene oxide synthase (AOS) and lipoxygenase (LOX2). On the other hand, wound-induced AOS gene expression was independent of NO. Furthermore, JA-responsive genes such as defensin (PDF1.2) were not induced, and NO induction of JA-biosynthesis enzymes did not result in elevated levels of JA. However, treatment with NO resulted in accumulation of salicylic acid (SA). In transgenic NahG plants (impaired in SA accumulation and/or signaling), NO did induce JA production and expression of JA-responsive genes. Altogether, the presented data demonstrate that wounding in Arabidopsis induces a fast accumulation of NO, and that NO may be involved in JA-associated defense responses and adjustments.

Cross Talk between Nitric Oxide and Phytohormones Regulate Plant Development during Abiotic Stresses

“…Later, Jih et al [150] demonstrated that SNP-derived NO delayed wounding-induced IPO expression, providing evidence for antagonistic association between NO and JA. In Arabidopsis, NO treatments led to elevated expression of key enzymes of the octadecanoid pathway, like LOX2, AOS, or OPR3, in wounded leaf epidermis [151]. However, this induction did not inluence JA responsible genes, like PDF1.2, hence supporting the earlier evidences about NO and JA association.…”

An Iron-induced Nitric Oxide Burst Precedes Ubiquitin-dependent Protein Degradation for Arabidopsis AtFer1 Ferritin Gene Expression

“…After overlaying by the glass cover, the slides were placed under the microscope, and the images were taken within 5 min on the same cells for each treatment. Settings and laser of the Zeiss Axiovert 100M inverted microscope were as described previously (31). Microscope, laser, and photomultiplier settings were held constant during the course of an experiment to obtain comparable data.…”

Peroxisomes Are Required for in Vivo Nitric Oxide Accumulation in the Cytosol following Salinity Stress of Arabidopsis Plants

“…This plant has been used in many plant studies to determine the involvement of NO in seed germination (Beligni and Lamattina, 2000;Batak et al, 2002;Bethke et al, 2006), biotic stress (Delledonne et al, 1998(Delledonne et al, , 2001), abiotic stress (Mackerness et al, 2001;Huang et al, 2004), programmed cell death (Clarke et al, 2000;Zhang et al, 2003), stomatal closure (Garcia-Mata et al, 2003;Desikan et al, 2004), iron metabolism (Murgia et al, 2004;Perazzolli et al, 2004), flowering (He et al, 2004;Simpson, 2005), and the protein S-nitrosylation (Feechan et al, 2005;Lindermayr et al, 2005), among others. Using the DAF-FM DA as a fluorescence probe, our results provide a detailed picture of the overall distribution of NO during the early development of 3-to 11-d-old Arabidopsis seedlings.…”