[A model for screening anti-viral agents based on yeast killer system]

Area of Science:

• Virology
• Microbiology
• Pharmacology

Background:

• The L-A virus in yeast exhibits -1 frameshifting, essential for M1 virus production and K1 toxin activity.
• Reduced K1 toxin activity leads to a diminished inhibition zone, providing a basis for antiviral screening.
• Developing efficient methods to screen for antiviral agents is crucial for combating viral infections.

Purpose of the Study:

• To develop a model for screening antiviral agents based on the L-A virus's altered frameshifting efficiency.
• To optimize the conditions for assaying the killing activity of potential antiviral compounds.
• To identify natural compounds with antiviral properties using the developed screening model.

Main Methods:

• Altering the -1 frameshifting efficiency of the L-A virus in yeast strains T158c/S14a.
• Developing a screening model based on the size of the inhibition zone on methylene blue agar at low pH.
• Optimizing assay conditions, including pH (4.3-4.7) and temperature (20-22°C), for well test assays.
• Screening several Chinese crude drugs for antiviral activity.

Main Results:

• A reduction in M1 virus and K1 toxin was observed upon altering L-A virus frameshifting efficiency.
• The developed screening model effectively correlated inhibition zone size with antiviral activity.
• Optimal conditions for the well test assay were determined to be pH 4.3-4.7 and 20-22°C.
• Flos Lonicerae and Rhizoma Cimicifugae demonstrated significant antiviral effects in the screening model.

Conclusions:

• A novel and effective screening model for antiviral agents was established using the L-A virus system.
• The model's optimal assay conditions were identified, facilitating reliable antiviral screening.
• Chinese crude drugs, specifically Flos Lonicerae and Rhizoma Cimicifugae, possess notable antiviral properties.
• This research lays the foundation for high-throughput screening of antiviral agents.