Modified telomeric repeat amplification protocol: a quantitative radioactive assay for telomerase without using...

Area of Science:

• Biochemistry
• Molecular Biology
• Enzyme Assays

Background:

• Telomerase is a crucial enzyme for maintaining telomere length.
• Accurate quantification of telomerase activity is vital for cell biology and cancer research.
• Existing assays often require complex procedures like electrophoresis.

Purpose of the Study:

• To develop a quantitative, PCR-based radioactive assay for telomerase activity.
• To create an assay that does not require electrophoretic evaluation.
• To establish a method suitable for cell-biological studies and inhibitor screening.

Main Methods:

• Developed a telomerase PCR-TRAP (TP-TRAP) assay utilizing a 20-mer oligonucleotide substrate (MTS).
• Incorporated [(3)H]dTTP for radioactive labeling during PCR amplification with two reverse primers (RPC3, RP).
• Isolated amplified radioactive dsDNA via precipitation and filtration for radioactivity determination.

Main Results:

• The TP-TRAP assay is quantitative and does not require electrophoresis.
• Telomerase product length remains constant during amplification due to specific primer use and PCR protocol.
• The assay demonstrated linearity and accuracy, suitable for detecting subtle changes in telomerase activity.
• Successfully used to screen a chemically modified oligonucleotide reverse transcriptase inhibitor.

Conclusions:

• The TP-TRAP assay provides a sensitive, accurate, and efficient method for quantifying telomerase activity.
• This assay is valuable for cell-biological research and the development of telomerase inhibitors.
• TP-TRAP simplifies telomerase activity measurement, enhancing its applicability in various research settings.