Fluorescent S1 nuclease assay utilizing exponential strand displacement amplification

Area of Science:

• Biochemistry
• Molecular Biology
• Enzyme Assays

Background:

• S1 nuclease is a critical enzyme involved in DNA processing.
• Accurate and sensitive methods for quantifying S1 nuclease activity are essential for biological research and drug discovery.
• Existing methods may lack sensitivity or require complex procedures.

Purpose of the Study:

• To develop a simple, label-free strategy for determining S1 nuclease activity.
• To establish a sensitive assay for S1 nuclease activity measurement.
• To demonstrate the utility of the assay for screening S1 nuclease inhibitors.

Main Methods:

• Utilized exponential strand displacement amplification (eSDA) as the core amplification technique.
• Designed a DNA probe susceptible to S1 nuclease degradation.
• Employed SYBR Green I, a double-stranded DNA-specific fluorescent dye, for signal detection.
• Leveraged target-induced inhibition of eSDA by S1 nuclease activity.

Main Results:

• Achieved selective and sensitive quantification of S1 nuclease activity.
• Demonstrated a significant reduction in fluorescence upon S1 nuclease activity due to blocked eSDA.
• Successfully validated the system's capability for screening potential S1 nuclease inhibitors.

Conclusions:

• The developed method offers a simple and label-free approach for S1 nuclease activity determination.
• The assay exhibits high sensitivity and selectivity for S1 nuclease.
• This novel strategy is effective for screening S1 nuclease inhibitors, with potential applications in drug discovery.