Related Experiment Videos
Sequence-specific fluorescent labeling of double-stranded DNA observed at the single molecule level
Bénédicte Géron-Landre1, Thibaut Roulon, Pierre Desbiolles
1Laboratoire de Biophysique, Muséum National d'Histoire Naturelle, INSERM U565, CNRS UMR8646, 43, rue Cuvier, 75231 Paris Cedex 05, France.
Nucleic Acids Research
|October 8, 2003
Summary
Researchers developed a novel method to fluorescently label short DNA sequences using triplex-forming oligonucleotides and DNA ligase. This technique enables precise visualization and potential manipulation of specific DNA segments.
Area of Science:
- Molecular Biology
- Biotechnology
- Genomics
Background:
- Accurate detection of short DNA sequences is crucial for molecular biology applications.
- Existing methods for DNA labeling and visualization have limitations in sensitivity and specificity for short sequences.
Purpose of the Study:
- To develop a novel method for fluorescent labeling of specific, short double-stranded DNA (dsDNA) sequences.
- To enable precise localization and potential micromanipulation of labeled DNA fragments.
Main Methods:
- Utilizing a stem-loop triplex-forming oligonucleotide (TFO) to bind a target dsDNA sequence.
- Ligating a fluorescent dsDNA fragment to the TFO after ligand-induced triple helix formation.
- Visualizing the labeled DNA using fluorescence microscopy and DNA combing techniques.
Main Results:
- Successfully fluorescently labeled a 15 bp non-repeated sequence on lambda DNA.
- Localized the fluorescent label at a specific position (4.2 +/- 0.5 kb) consistent with the target sequence.
- Observed an alternative DNA combing mechanism initiated from the fluorescent label.
Conclusions:
- The described method provides a new tool for detecting and localizing very short dsDNA sequences.
- This technique offers potential for advanced applications in single DNA molecule micromanipulation and analysis.