ATP-Stimulated, DNA-Mediated Redox Signaling by XPD, a DNA Repair and Transcription Helicase
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, and may reflect a general biological role for DNA charge transport.
© 2011 American Chemical Society. Received: August 1, 2011. Publication Date (Web): September 22, 2011. This research was supported by the NIH (GM49216 to J.K.B. and CA112093 to J.A.T.) and the DOE (ENIGMA program under Contract No. DE-AC02-05CH11231 to J.A.T.). T.P.M. also thanks the NSF for a graduate fellowship.
Accepted Version - nihms328262.pdf
Supplemental Material - ja207222t_si_001.pdf