Miniaturised interaction proteomics on a microfluidic platform with ultra-low input requirements.

Area of Science:

• Biochemistry
• Molecular Biology
• Proteomics

Background:

• Protein-protein interactions (PPIs) are fundamental to cellular processes.
• Affinity purification coupled to mass spectrometry (AP-MS) is a key technique for identifying PPIs.
• Traditional AP-MS methods require substantial amounts of biological material.

Purpose of the Study:

• To develop a microfluidic-based AP-MS workflow (on-chip AP-MS) for PPI identification.
• To enable PPI analysis using significantly reduced input material.
• To demonstrate the versatility of the on-chip AP-MS platform for both tagged and native proteins.

Main Methods:

• Implementation of a microfluidic-based automated platform for AP-MS.
• Purification of protein complexes from minute amounts of cellular lysate (as low as 4 micrograms).
• Application of the on-chip AP-MS workflow to identify components of human Cohesin, CCC, and Mediator complexes.

Main Results:

• Achieved a 50-100 fold downscaling of input material compared to conventional methods.
• Successfully purified tagged baits and native cellular proteins with their interaction partners.
• Demonstrated the efficacy of the on-chip AP-MS workflow for complex protein mixture analysis.

Conclusions:

• The on-chip AP-MS workflow offers a highly sensitive method for PPI identification.
• This technology significantly reduces sample requirements, making PPI analysis more accessible.
• The platform holds substantial potential for biological and clinical research involving limited sample quantities.