TY - JOUR
T1 - Molecular basis for the redox control of nuclear transport of the structural chromatin protein Hmgb1
AU - Hoppe, George
AU - Talcott, Katherine E.
AU - Bhattacharya, Sanjoy K.
AU - Crabb, John W.
AU - Sears, Jonathan E.
N1 - Funding Information:
This work was supported by Grant-in-aid #0555235B from the American Heart Association (to G.H.), K12HD049091/NIH/NICHD (to JS), the Thomas R. Lee Award for National Glaucoma Research Program of American Health Assistance Foundation (to S.K.B.) and NIH grants EY015266 (to S.K.B.), EY06603, EY014239, and EY015638 (to J.W.C.). Authors are indebted to Dr. Marco Bianchi (San Raffaele Research Institute, Milan, Italy) for the kind gift of plasmid encoding Hmgb1-EGFP. We thank Karen A. West and Dr. Bruce Levison for conducting mass spectrometry and Dr. Jian Sun for her assistance with bioinformatics.
PY - 2006/11/1
Y1 - 2006/11/1
N2 - Oxidative stress can induce a covalent disulfide bond between protein and peptide thiols that is reversible through enzymatic catalysis. This process provides a post-translational mechanism for control of protein function and may also protect thiol groups from irreversible oxidation. High mobility group protein B1 (Hmgb1), a DNA-binding structural chromosomal protein and transcriptional co-activator was identified as a substrate of glutaredoxin. Hmgb1 contains 3 cysteines, Cys23, 45, and 106. In mild oxidative conditions, Cys23 and Cys45 readily form an intramolecular disulfide bridge, whereas Cys106 remains in the reduced form. The disulfide bond between Cys23 and Cys45 is a target of glutathione-dependent reduction by glutaredoxin. Endogenous Hmgb1 as well as GFP-tagged wild-type Hmgb1 co-localize in the nucleus of CHO cells. While replacement of Hmgb1 Cys23 and/or 45 with serines did not affect the nuclear distribution of the mutant proteins, Cys106-to-Ser and triple cysteine mutations impaired nuclear localization of Hmgb1. Our cysteine targeted mutational analysis suggests that Cys23 and 45 induce conformational changes in response to oxidative stress, whereas Cys106 appears to be critical for the nucleocytoplasmic shuttling of Hmgb1.
AB - Oxidative stress can induce a covalent disulfide bond between protein and peptide thiols that is reversible through enzymatic catalysis. This process provides a post-translational mechanism for control of protein function and may also protect thiol groups from irreversible oxidation. High mobility group protein B1 (Hmgb1), a DNA-binding structural chromosomal protein and transcriptional co-activator was identified as a substrate of glutaredoxin. Hmgb1 contains 3 cysteines, Cys23, 45, and 106. In mild oxidative conditions, Cys23 and Cys45 readily form an intramolecular disulfide bridge, whereas Cys106 remains in the reduced form. The disulfide bond between Cys23 and Cys45 is a target of glutathione-dependent reduction by glutaredoxin. Endogenous Hmgb1 as well as GFP-tagged wild-type Hmgb1 co-localize in the nucleus of CHO cells. While replacement of Hmgb1 Cys23 and/or 45 with serines did not affect the nuclear distribution of the mutant proteins, Cys106-to-Ser and triple cysteine mutations impaired nuclear localization of Hmgb1. Our cysteine targeted mutational analysis suggests that Cys23 and 45 induce conformational changes in response to oxidative stress, whereas Cys106 appears to be critical for the nucleocytoplasmic shuttling of Hmgb1.
KW - Chromatin remodeling
KW - Cysteine
KW - GFP
KW - Glutaredoxin
KW - High mobility group
KW - Oxidative stress
KW - Thiol-disulfide reactions
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U2 - 10.1016/j.yexcr.2006.07.020
DO - 10.1016/j.yexcr.2006.07.020
M3 - Article
C2 - 16962095
AN - SCOPUS:33749125188
VL - 312
SP - 3526
EP - 3538
JO - Experimental Cell Research
JF - Experimental Cell Research
SN - 0014-4827
IS - 18
ER -