TY - JOUR
T1 - Thioredoxin catalyzes the s-nitrosation of the caspase-3 active site cysteine
AU - Mitchell, Douglas A.
AU - Marletta, Michael A.
N1 - Funding Information:
We wish to thank A. Falick (University of California, Berkeley) for acquiring the CID spectra. We also thank members of the Marletta laboratory for helpful discussions and critical review of the manuscript. This work is supported in part by grants from the DeBenedictis Fund of University of California, Berkeley to M.A.M. and US National Institutes of Health grant CA 26731.
PY - 2005/8
Y1 - 2005/8
N2 - Nitric oxide (NO) signaling through the formation of cGMP is well established; however, there seems to be an increasing role for cGMP-independent NO signaling. Although key molecular details remain unanswered, S-nitrosation represents an example of cGMP-independent NO signaling. This modification has garnered recent attention as it has been shown to modulate the function of several important biochemical pathways1-3. Although an analogy to O-phosphorylation can be drawn4, little is known about protein nitrosothiol regulation in vivo. In solution, NO readily reacts with oxygen to yield a nitrosating agent, but this process alone provides no specificity for nitrosation5. This lack of specificity is exemplified by the in vitro poly-S-nitrosation of caspase-3 (Casp-3, ref. 6) and the ryanodine receptor7.Previous in vivo work with Casp-3 suggests that a protein-assisted process may be responsible for selective S-nitrosation of the catalytic cysteine (Cys163)8. We demonstrated that a single cysteine in thioredoxin (Trx) is capable of a targeted, reversible transnitrosation reaction with Cys163 of Casp-3. A greater understanding of how S-nitrosation is mediated has broad implications for cGMP-independent signaling. The example described here also suggests a new role for Trx in the regulation of apoptosis.
AB - Nitric oxide (NO) signaling through the formation of cGMP is well established; however, there seems to be an increasing role for cGMP-independent NO signaling. Although key molecular details remain unanswered, S-nitrosation represents an example of cGMP-independent NO signaling. This modification has garnered recent attention as it has been shown to modulate the function of several important biochemical pathways1-3. Although an analogy to O-phosphorylation can be drawn4, little is known about protein nitrosothiol regulation in vivo. In solution, NO readily reacts with oxygen to yield a nitrosating agent, but this process alone provides no specificity for nitrosation5. This lack of specificity is exemplified by the in vitro poly-S-nitrosation of caspase-3 (Casp-3, ref. 6) and the ryanodine receptor7.Previous in vivo work with Casp-3 suggests that a protein-assisted process may be responsible for selective S-nitrosation of the catalytic cysteine (Cys163)8. We demonstrated that a single cysteine in thioredoxin (Trx) is capable of a targeted, reversible transnitrosation reaction with Cys163 of Casp-3. A greater understanding of how S-nitrosation is mediated has broad implications for cGMP-independent signaling. The example described here also suggests a new role for Trx in the regulation of apoptosis.
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U2 - 10.1038/nchembio720
DO - 10.1038/nchembio720
M3 - Article
C2 - 16408020
AN - SCOPUS:33644818614
SN - 1552-4450
VL - 1
SP - 154
EP - 158
JO - Nature Chemical Biology
JF - Nature Chemical Biology
IS - 3
ER -