S-Nitrosylation — another biological switch like phosphorylation?

Abstract

Nitric oxide (NO) has emerged as a key-signaling molecule affecting plant growth and development right from seed germination to cell death. It is now being considered as a new plant hormone. NO is predominantly produced by nitric oxide synthase (NOS) in animal systems. NOS converts L-arginine (substrate) to citrulline and NO is a byproduct of the reaction. However, a similar biosynthetic mechanism is still not fully established in plants as NOS is still to be purified. First plant NOS gene (AtNOS1) was cloned from Arabidopsis suggesting the existence of NOS in plants. It was shown to be involved in hormonal signaling, stomatal closure, flowering, pathogen defense response, oxidative stress, senescence and salt tolerance. However, recent studies have raised critical questions/concerns about its substantial role in NO biosynthesis. Despite the ever increasing number of NO responses observed, little is known about the signal transduction pathway(s) and mechanisms by which NO interacts with different components and results in altered cellular activities. A brief overview is presented here. Proteins are one of the major bio-molecule besides DNA, RNA and lipids which are modified by NO and its derivatives. S-nitrosylation is a ubiquitous NO mediated posttranslational modification that might regulate broad spectrum of proteins. In this review S-nitrosylation formation, catabolism and its biological significance is discussed to present the current scenario of this modification in plants.

Roles of sodium hydrosulfide and sodium nitroprusside as priming molecules during drought acclimation in citrus plants

“…7cC), confirming that the photosynthetic system is targeted by S-nitrosylation (Lindermayr et al 2005). Most of the presented S-nitrosylated proteins were also identified previously in various plant systems (e.g., chlorophyll ab binding protein, elongation factor 1, glycolate oxidase, carbonic anhydrase; Lindermayr et al 2005;Abat et al 2008;Ortega-Galisteo et al 2012;Tanou et al 2009Tanou et al , 2012b, however this study pinpoints 2 S-nitrosylated proteins, namely aspartic proteinase nepehthesin-1 and stem-loop binding protein, that represent novel targets of Snitrosylation in plants. Of particular interest is also the fact that the S-nitrosylated protein targets can differ among treatments.…”

Physiological effects of exogenous nitric oxide on Brassica juncea seedlings under NaCl stress

“…Nitric oxide (NO) is a water and lipid soluble gaseous compound with high diffusion coefficient (Abat et al 2008). NO can mediate plant responses to biotic and abiotic stresses including drought (Tian andLei 2006, Zhang et al 2009) and salinity (Sheokand et al 2008, Xie et al 2008.…”

Identification of nuclear target proteins for S-nitrosylation in pathogen-treated Arabidopsis thaliana cell cultures

“…Because of the presence of an unpaired electron in its outer orbital, NO is a reactive free radical gas, which can exist in three different redox-related species, namely nitric oxide radical (NO • ), nitrosonium cation (NO + ), and nitroxyl anion (NO − ) [1,2]. NO also reacts with O 2 and O 2 − and generates NO x and peroxynitrite, respectively.…”