Interaction proteomics: characterization of protein complexes using tandem affinity purification-mass spectrometry

Area of Science:

• Proteomics
• Molecular Biology
• Biochemistry

Background:

• Cellular processes depend on multimeric protein complexes.
• Understanding these complexes requires identifying and characterizing their protein components.
• Mass spectrometry (MS) advances enable sensitive protein complex identification.

Purpose of the Study:

• To describe the tandem affinity purification coupled with mass spectrometry (TAP-MS) approach.
• To highlight its utility in isolating and characterizing native protein complexes.
• To demonstrate its broad applicability across different organisms.

Main Methods:

• Utilizes a tandem affinity purification (TAP) tag with two distinct affinity purification steps.
• Employs Protein A for initial purification and Tobacco Etch Virus (TEV) protease cleavage.
• Uses Calmodulin-Binding Peptide (CBP) and calmodulin beads for the second purification step, with calcium-dependent elution.
• Mass spectrometry (MS) is used for final protein identification.

Main Results:

• The TAP-MS approach effectively isolates native protein complexes.
• It allows for sensitive and accurate identification of protein components within complexes.
• The method has been successfully applied to various model organisms, including bacteria, yeast, mammalian cells, C. elegans, Drosophila, and mice.

Conclusions:

• TAP-MS is a powerful and versatile technique for characterizing protein complexes.
• It provides crucial insights into the composition of molecular machines driving cellular functions.
• This methodology facilitates a deeper understanding of biological pathways and cellular events.