AuNP-CTG based probing system targeting CAG repeat DNA and RNA sequences

Area of Science:

• Biotechnology
• Molecular Biology
• Nanotechnology

Background:

• CAG repeat sequences are associated with various neurological disorders.
• Accurate detection of these sequences is crucial for diagnosis and research.
• Existing detection methods may lack sensitivity or require complex procedures.

Purpose of the Study:

• To develop a novel gold nanoparticle-colloidal gold (AuNP-CTG) based probing system.
• To enable sensitive detection of CAG repeat sequences in DNA and RNA.
• To demonstrate the system's applicability in cellular environments.

Main Methods:

• Synthesis of a AuNP-CTG based probing system.
• Utilizing rolling circle amplification (RCA) for signal amplification.
• Employing fluorescence changes to indicate target detection.
• Testing the system in HeLa cells for DNA and RNA detection.

Main Results:

• The AuNP-CTG system successfully detected various lengths of CAG repeat sequences.
• The system demonstrated efficient transfection into HeLa cells without reagents.
• Significant fluorescence changes were observed upon detection of target CAG repeats.
• The system exhibited high sensitivity, detecting picomolar amounts of target DNA with signal amplification.
• Detection of RNA CAG repeat sequences was also achieved.

Conclusions:

• The developed AuNP-CTG probing system offers a sensitive and versatile method for detecting DNA and RNA CAG repeat sequences.
• The system's ability to function within cells without transfection reagents simplifies experimental procedures.
• This technology holds promise for diagnostic applications and further research into CAG repeat-associated diseases.