Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 108, Issue 35, Pages E600-E606Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1110736108
Keywords
cysteine; nitric oxide; S-nitrosoglutathione; transnitrosation
Categories
Funding
- Massachusetts Institute of Technology (MIT)
- American Cancer Society
- National Institutes of Health (NIH) [CA26731, GM080272]
- MIT Center for Environmental Health Sciences [ES002109]
Ask authors/readers for more resources
Protein S-nitrosation on cysteine residues has emerged as an important posttranslational modification in mammalian cells. Previous studies have suggested a primary role for thioredoxin (Trx) in controlling protein S-nitrosation reactions. Human Trx contains five conserved Cys, including two redox-active catalytic Cys (Cys32 and Cys35) and three non-active-site Cys (Cys62, Cys69, and Cys73), all of which have been reported as targets of S-nitrosation. Prior reports have studied thermodynamic end points of nitrosation reactions; however, the kinetics of Trx nitrosation has not previously been investigated. Using the transnitrosation agent, S-nitrosoglutathione, a kinetic analysis of the selectivity and redox dependence of Trx nitrosation at physiologically relevant concentrations and times was performed, utilizing a mass spectrometry-based method for the direct analysis of the nitrosated Trx. Reduced Trx (rTrx) was nitrosated 2.7-times faster than oxidized Trx (oTrx), and rTrx was nitrosated selectively on Cys62, whereas oTrx was nitrosated only on Cys73. These sites of nitrosation were confirmed at the peptide level using a novel modification of the biotin-switch technique called the reductive switch. These results suggest separate signaling pathways for Trx-SNO under different cellular redox states.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available