S-Nitrosylated proteins in pea (Pisum sativum L.) leaf peroxisomes: changes under abiotic stress

Abstract

Peroxisomes, single-membrane-bounded organelles with essentially oxidative metabolism, are key in plant responses to abiotic and biotic stresses. Recently, the presence of nitric oxide (NO) described in peroxisomes opened the possibility of new cellular functions, as NO regulates diverse biological processes by directly modifying proteins. However, this mechanism has not yet been analysed in peroxisomes. This study assessed the presence of S-nitrosylation in pea-leaf peroxisomes, purified S-nitrosylated peroxisome proteins by immunoprecipitation, and identified the purified proteins by two different mass-spectrometry techniques (matrix-assisted laser desorption/ionization tandem time-of-flight and two-dimensional nano-liquid chromatography coupled to ion-trap tandem mass spectrometry). Six peroxisomal proteins were identified as putative targets of S-nitrosylation involved in photorespiration, β-oxidation, and reactive oxygen species detoxification. The activity of three of these proteins (catalase, glycolate oxidase, and malate dehydrogenase) is inhibited by NO donors. NO metabolism/S-nitrosylation and peroxisomes were analysed under two different types of abiotic stress, i.e. cadmium and 2,4-dichlorophenoxy acetic acid (2,4-D). Both types of stress reduced NO production in pea plants, and an increase in S-nitrosylation was observed in pea extracts under 2,4-D treatment while no total changes were observed in peroxisomes. However, the S-nitrosylation levels of catalase and glycolate oxidase changed under cadmium and 2,4-D treatments, suggesting that this post-translational modification could be involved in the regulation of H2O2 level under abiotic stress.

ROS, Calcium, and Electric Signals: Key Mediators of Rapid Systemic Signaling in Plants

“…NO-mediated S-nitrosylation was also shown to inhibit ROS scavenging enzymes such as catalase and ascorbate peroxidase (Ortega-Galisteo et al, 2012;de Pinto et al, 2013), suggesting that NO could also promote an increase in H 2 O 2 by reducing its decay (Suzuki et al, 2013). Moreover, glutaredoxin S12 in the chloroplast and Gly decarboxylase in the mitochondria were shown to be targets of glutathionylation, and these posttranslational modifications might also contribute to the regulation of ROS levels in cells (Palmieri et al, 2010; for review, see Zaffagnini et al, 2012).…”

Insights into the toxicity mechanism of and cell response to the herbicide 2,4-D in plants

“…A reduction of this molecule has been reported in pea leaves treated with 2,4-D as well as an induction of nitrosoglutathione reductase activity, and changes in the S-nitrosylation of peroxisomal proteins. 11 The role of NO under these conditions is not clear but it can participate with ROS in the regulation of different process such as stomatal movement or gene regulation.…”

Modulation of Protein S-Nitrosylation by Isoprene Emission in Poplar

“…However, the enzymatic removal of the NO group via denitrosylation has been reported (Benhar et al, 2009), ensuring the reversibility of the modification. S-Nitrosylation and denitrosylation events together form the S-nitrosylation pattern of a cell under physiological conditions, which may strongly change upon stress (Abat and Deswal, 2009;Ortega-Galisteo et al, 2012). The S-nitrosylation of enzymes can either inhibit or activate their functions (Astier et al, 2012).…”