A Yeast-Based High-Throughput Screening Platform for the Discovery of Novel pre-mRNA Splicing Modulators

Area of Science:

• Molecular Biology
• Genetics
• Drug Discovery

Background:

• Pre-messenger RNA (pre-mRNA) splicing is vital for eukaryotic gene expression.
• Dysregulation of splicing is implicated in numerous diseases.
• Few small molecules exist to modulate splicing or inhibit splicing machinery.

Purpose of the Study:

• To establish a novel high-throughput screening (HTS) platform for identifying splicing-modulating compounds.
• To discover small molecules that can inhibit pre-mRNA splicing.
• To investigate the therapeutic potential of identified compounds in cancer models.

Main Methods:

• A two-tiered screening approach using yeast (*S. cerevisiae*) strains.
• Primary screen: measuring growth inhibition in sensitized yeast strains.
• Secondary screen: utilizing fluorescent protein production as a readout for splicing inhibition.

Main Results:

• Identified 4 small molecules that induce accumulation of unspliced pre-mRNA *in vivo* in yeast.
• One compound demonstrated increased sensitivity in cancer cells with an SRSF2^P95H mutation compared to wild-type.
• Transcriptome analysis revealed widespread gene expression changes in sensitive cells.

Conclusions:

• The yeast-based HTS platform is effective for identifying compounds that alter pre-mRNA splicing outcomes.
• The identified compounds represent potential leads for developing novel therapeutics targeting splicing dysregulation.
• This approach offers a powerful tool for drug discovery in splicing-related diseases.