Detection of Protein S-nitrosothiols (SNOs) in Plant Samples on Diaminofluorescein (DAF) Gels

In plant cells, the analysis of protein S-nitrosothiols (SNOs) under physiological and adverse stress conditions is essential to understand the mechanisms of Nitric oxide (NO)-based signaling. We adapted a previously reported protocol for detecting protein SNOs in animal systems ( King et al., 2005 ) for plant samples. Briefly, proteins from plant samples are separated via non-reducing SDS-PAGE, then the NO bound by S-nitrosylated proteins is released using UV light and, finally, the NO is detected using the fluorescent probe DAF-FM (Rodriguez-Ruiz et al., 2017). Thus, the approach presented here provides a relatively quick and economical procedure that can be used to compare protein SNOs content in plant samples and provide insight in NO-based signaling in plants.