Applying UV crosslinking to study RNA-protein interactions in multicomponent ribonucleoprotein complexes

Area of Science:

• Molecular Biology
• Biochemistry
• Genetics

Background:

• Ribonucleoprotein complexes (RNPs) are essential for numerous biological functions.
• Understanding RNA-protein interactions within RNPs is critical for deciphering cellular mechanisms.

Purpose of the Study:

• To establish an experimental approach for identifying protein-binding sites on RNA within RNPs.
• To demonstrate the utility of UV crosslinking for mapping RNA-protein interactions in a model system.

Main Methods:

• Utilized a hexahistidine-tagged protein component for purification of Saccharomyces cerevisiae RNase P/MRP RNPs.
• Employed UV crosslinking to covalently link proteins to bound RNA.
• Isolated tagged proteins and co-isolated crosslinked RNA, followed by enzymatic degradation of protein and purification of RNA.
• Identified crosslink locations using primer extension with reverse transcriptase and gel electrophoresis.

Main Results:

• Successfully mapped protein-binding sites on RNA within RNase P/MRP RNPs.
• Demonstrated the co-isolation of crosslinked RNA with its interacting protein component.
• Validated the primer extension method for precise localization of RNA-protein crosslinks.

Conclusions:

• The described UV crosslinking approach is effective for identifying RNA-binding sites of proteins in complex RNPs.
• This method provides valuable insights into the architecture and function of RNPs.
• The technique is applicable to all protein components within RNase P/MRP complexes.