Protein glutathionylation in respiratory epithelial cell lines

Glutathionylation is a reversible binding of glutathione (GSH) to SH-groups of proteins. Activity of many critical proteins (e.g. protein tyrosine phosphatase 1b, NF-kappaB, AP-1), involved in signal transduction during inflammation and oxidative stress, may be regulated through glutathionylation. Recently, a protocol using a biotinylated glutathione monoester to identify glutathionylated proteins was published (Sullivan DM et al, 2002). For our experiments, we modified this procedure and studied protein glutathionylation in respiratory epithelial cell lines (16HBE14o-, gift from Prof. D. Gruenert and A549, obtained from ATCC) exposed to hydrogen peroxide (1 or 24h). Glutathionylated proteins were affinity-purified from cell lysates and subjected to 2D gel electrophoresis. The described procedure revealed four glutathionylated proteins in hydrogen peroxide-stimulated samples. The mass-spectrometric identification of glutathionylated proteins is underway.

Conclusion: protein glutathionylation is documented in respiratory epithelial cell lines. Further studies are planned to study the significance of protein glutathionylation in signal transduction during oxidative stress and glutathione augmentation.

Supported by: NSERC and Canadian CF Foundation