Single molecule approaches for studying spliceosome assembly and catalysis

Area of Science:

• Molecular Biology
• Biochemistry
• Cell Biology

Background:

• Single molecule assays offer unique insights into complex biological processes like pre-mRNA splicing.
• Existing technologies for studying splicing and spliceosome assembly have limitations.
• Visualizing molecular interactions in real-time is crucial for understanding gene expression regulation.

Purpose of the Study:

• To establish a robust protocol for single molecule fluorescence microscopy of spliceosome assembly.
• To enable the visualization of individual pre-mRNA molecules and spliceosome components during assembly.
• To provide a complementary approach to existing methods for studying pre-mRNA processing.

Main Methods:

• Fluorescently labeling pre-mRNAs using splinted RNA ligation.
• Generating fluorescent spliceosome subunits via SNAP-tagging proteins in cell lysate.
• Passivating glass slides with polyethylene glycol for total internal reflection fluorescence (TIRF) microscopy.
• Tethering fluorescent pre-mRNAs to the slide surface and introducing labeled spliceosome components.

Main Results:

• Successful production of fluorescent RNA and protein reagents.
• Demonstration of a passivated surface suitable for TIRF microscopy.
• Visualization of spliceosome assembly dynamics at the single molecule level.
• Analysis of spliceosome assembly using single molecule fluorescence techniques.

Conclusions:

• The developed single molecule assay provides a powerful tool for studying spliceosome assembly.
• This method complements existing techniques, offering higher resolution and dynamic insights.
• The protocol facilitates detailed investigation into the mechanisms of pre-mRNA processing and gene regulation.