ATP-stimulated, DNA-mediated redox signaling by XPD, a DNA repair and transcription helicase.
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ABSTRACT:
SUBMITTER: Mui TP
PROVIDER: S-EPMC3234108 | biostudies-other | 2011 Oct
REPOSITORIES: biostudies-other
Publications
ATP-stimulated, DNA-mediated redox signaling by XPD, a DNA repair and transcription helicase.
Mui Timothy P TP Fuss Jill O JO Ishida Justin P JP Tainer John A JA Barton Jacqueline K JK
Journal of the American Chemical Society 20110922 41
Using DNA-modified electrodes, we show DNA-mediated signaling by XPD, a helicase that contains a [4Fe-4S] cluster and is critical for nucleotide excision repair and transcription. The DNA-mediated redox signal resembles that of base excision repair proteins, with a DNA-bound redox potential of ~80 mV versus NHE. Significantly, this signal increases with ATP hydrolysis. Moreover, the redox signal is substrate-dependent, reports on the DNA conformational changes associated with enzymatic function, ...[more]
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