@article {685,
	title = {S-Glutathionylation of p47phox sustains superoxide generation in activated neutrophils. [Mass Spectrometry Facility - Proteomics]},
	journal = {Biochim Biophys Acta},
	volume = {1865},
	year = {2018},
	month = {2018 Feb},
	pages = {444-454},
	abstract = {<p>Post-translational modifications (PTMs) induced conformational changes of proteins can cause their activation or inactivation. Neutrophils clear pathogen through phagocytosis and oxidative burst generation, while participate in inflammation through sustained and uncontrolled generation of ROS. In activated PMNs, cytosolic NOX-2 subunit p47phox following phosphorylation interacts with p67phox, p40phox and along with Rac2 translocate to the membrane. Phosphorylation of p47phox subunit occurs in both short spurts as well as sustained ROS generation, suggesting towards the unidentified molecular mechanism(s) driving these two diverse outcomes by various stimuli. The present study demonstrates that in PMA or NO treated neutrophils a subunit of NOX2, p47phox gets glutathionylated to sustain ROS generation along with a decrease in catalase, Grx-1 activity and change in GSH/GSSG ratio. Surprisingly, fMLP treated cells neither showed sustained ROS production nor glutathionylation of p47phox. S-Glutathionylation was always secondary to phosphorylation of p47phox and inhibition of glutathionylation did not alter phosphorylation but specifically impaired sustained ROS production. Interestingly, forced S-glutathionylation of p47phox converted the fMLP induced ROS generation into sustained release of ROS. We then identified the glutathionylation susceptible cysteine residues of p47phox by LC-MS/MS with IAM switch mapping. Site-directed mutagenesis of cysteine residues further mitigated p47phox S-glutathionylation. Thus, we demonstrate that p47phox S-glutathionylation plays an essential key role in the sustained ROS generation by human neutrophils.</p>
},
	issn = {0006-3002},
	doi = {10.1016/j.bbamcr.2017.11.014},
	author = {Nagarkoti, Sheela and Dubey, Megha and Awasthi, Deepika and Kumar, Vikas and Chandra, Tulika and Kumar, Sachin and Dikshit, Madhu}
}
@article {513,
	title = {L-Plastin S-glutathionylation promotes reduced binding to β-actin and affects neutrophil functions. (Mass Spectrometry)},
	journal = {Free Radic Biol Med},
	volume = {86},
	year = {2015},
	month = {2015 Sep},
	pages = {1-15},
	abstract = {<p>Posttranslational modifications (PTMs) of cytoskeleton proteins due to oxidative stress associated with several pathological conditions often lead to alterations in cell function. The current study evaluates the effect of nitric oxide (DETA-NO)-induced oxidative stress-related S-glutathionylation of cytoskeleton proteins in human PMNs. By using in vitro and genetic approaches, we showed that S-glutathionylation of L-plastin (LPL) and β-actin promotes reduced chemotaxis, polarization, bactericidal activity, and phagocytosis. We identified Cys-206, Cys-283, and Cys-460as S-thiolated residues in the β-actin-binding domain of LPL, where cys-460 had the maximum score. Site-directed mutagenesis of LPL Cys-460 further confirmed the role in the redox regulation of LPL. S-Thiolation diminished binding as well as the bundling activity of LPL. The presence of S-thiolated LPL was detected in neutrophils from both diabetic patients and db/db mice with impaired PMN functions. Thus, enhanced nitroxidative stress may results in LPL S-glutathionylation leading to impaired chemotaxis, polarization, and bactericidal activity of human PMNs, providing a mechanistic basis for their impaired functions in diabetes mellitus.</p>
},
	keywords = {Actins, Adult, Amino Acid Sequence, Animals, Case-Control Studies, Cell Polarity, Chemotaxis, Diabetes Mellitus, Female, Glutathione, HEK293 Cells, Humans, Male, Mice, Inbred C57BL, Mice, Obese, Microfilament Proteins, Middle Aged, Molecular Sequence Data, Neutrophils, Nitric Oxide, Oxidative Stress, Protein Binding, Protein Processing, Post-Translational, Young Adult},
	issn = {1873-4596},
	doi = {10.1016/j.freeradbiomed.2015.04.008},
	author = {Dubey, Megha and Singh, Abhishek K and Awasthi, Deepika and Nagarkoti, Sheela and Kumar, Sachin and Ali, Wahid and Chandra, Tulika and Kumar, Vikas and Barthwal, Manoj K and Jagavelu, Kumaravelu and S{\'a}nchez-G{\'o}mez, Francisco J and Lamas, Santiago and Dikshit, Madhu}
}
