Near‐field optical imaging of abasic sites on a single DNA molecule

FEBS Letters

Kawai, Tomoji¹  Kim, JongMin¹  Lee, HeaYeon¹  Muramatsu, Hiroshi² 

[1] ISIR-Sanken, Osaka University, 8-1 Mohogaoka, Ibaraki, Osaka 567-0047, Japan;School of Bionics, Tokyo University of Technology, Katakura, Hachioji, Tokyo 192-0982 Japan

关键词: Scanning near-field optical microscopy;    DNA damage;    DNA imaging;    Avidin–biotin interaction;    SNOM;    scanning near-field optical microscopy;    AP;    apurinic/apyrimidinic;    A532;    alexa 532;    FWHM;    full width half maximum;   

DOI  :  10.1016/S0014-5793(03)01298-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Scanning near-field optical microscopy (SNOM) imaging was performed to allow for the direct visualization of damaged sites on individual DNA molecules to a scale of a few tens of nanometers. Fluorescence in situ hybridization on extended DNA molecules was modified to detect a single abasic site. Abasic sites were specifically labelled with a biotinlylated aldehyde-reactive probe and fluorochrome-conjugated streptavidin. By optimizing the performance of the SNOM technique, we could obtain high contrast near-field optical images that enabled high-resolution near-field fluorescence imaging using optical fiber probes with small aperture sizes. High-resolution near-field fluorescence imaging demonstrated that two abasic sites within a distance of 120 nm are clearly obtainable, something which is not possible using conventional fluorescence in situ hybridization combined with far-field fluorescence microscopy.

【 授权许可】

Unknown