Signal Transduction through Dye-Labeled M-DNA Y-Branched Junctions:  Switching Modulated by Chemical Reduction of Anthraquinone

• Published in: Nano letters Vol. 3; no. 5; pp. 617 - 622
• Main Authors: Wettig, Shawn D, Bare, Grant A, Skinner, Ryan J. S, Lee, Jeremy S
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01-05-2003
• Subjects: Biological and medical sciences; Diverse techniques; Fundamental and applied biological sciences. Psychology; Molecular and cellular biology; Signal transduction; Biochemistry; Method; Molecular biology; DNA
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl034029n

Metal-DNA (M-DNA) is a complex formed between duplex DNA and divalent metal ions which facilitates electron transfer. In this study, 90 base-pair DNA Y-branched junctions were prepared with the electron donor fluorescein attached to one arm and electron acceptors, rhodamine or anthraquinone, to the other arms. Upon formation of M-DNA, the fluorescence of fluorescein was quenched by the electron acceptors, demonstrating that electron transfer could occur through the junction. As well, the quenching was modulated by chemical reduction of anthraquinone, mimicking a chemical switch. Base-pairing defects at the point of the junction were observed to have only a small impact on the quenching, demonstrating the robust nature of electron transfer in M-DNA. Therefore, M-DNA may have extraordinary potential for the development of nanoelectronic devices.