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Intermolecular disulfide bond formation in the NEMO dimer requires Cys54 and Cys347.

ABSTRACT: NEMO is an essential regulatory component of the IkappaB kinase (IKK) complex, which controls activation of the NF-kappaB signaling pathway. Herein, we show that NEMO exists as a disulfide-bonded dimer when isolated from several cell types and analyzed by SDS-polyacrylamide gel electrophoresis under non-reducing conditions. Treatment of cells with hydrogen peroxide (H(2)O(2)) induces further formation of NEMO dimers. Disulfide bond-mediated formation of NEMO dimers requires Cys54 and Cys347. The ability of these residues to form disulfide bonds is consistent with their location in a NEMO dimer structure that we generated by molecular modeling. We also show that pretreatment with H(2)O(2) decreases TNFalpha-induced IKK activity in NEMO-reconstituted cells, and that TNFalpha has a diminished ability to activate NF-kappaB DNA binding in cells reconstituted with NEMO mutant C54/347A. This study implicates NEMO as a target of redox regulation and presents the first structural model for the NEMO protein.

SUBMITTER: Herscovitch M

PROVIDER: S-EPMC2277332 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature

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Intermolecular disulfide bond formation in the NEMO dimer requires Cys54 and Cys347.

Herscovitch Melanie M Comb William W Ennis Thomas T Coleman Kate K Yong Sheila S Armstead Brinda B Kalaitzidis Demetrios D Chandani Sushil S Gilmore Thomas D TD

Biochemical and biophysical research communications 20071228 1

NEMO is an essential regulatory component of the IkappaB kinase (IKK) complex, which controls activation of the NF-kappaB signaling pathway. Herein, we show that NEMO exists as a disulfide-bonded dimer when isolated from several cell types and analyzed by SDS-polyacrylamide gel electrophoresis under non-reducing conditions. Treatment of cells with hydrogen peroxide (H(2)O(2)) induces further formation of NEMO dimers. Disulfide bond-mediated formation of NEMO dimers requires Cys54 and Cys347. The ...[more]

PMID: 18164680

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Intermolecular disulfide bond formation in the NEMO dimer requires Cys54 and Cys347.

Publications

Intermolecular disulfide bond formation in the NEMO dimer requires Cys54 and Cys347.

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