2022 Volume 7 Issue 1 Pages 9-14
The immunoprecipitation-mass spectrometry (IP-MS) method, in which protein complexes are immunoprecipitated from extracts of biological samples and the precipitates are analyzed by mass spectrometry after enzymatic digestion, is useful to elucidate biological functions of target proteins. IP-MS can globally identify and quantify various post-translational modifications and interacting proteins of the target proteins. We have performed numerous IP-MS experiments on various types of proteins, including cytoplasmic, nuclear, membrane, and extracellular proteins, and have optimized the experimental protocols. As a result, it has become clear that the conditions of various steps of immunoprecipitation should be changed for IP-MS compared to conventional Western blot analysis of immunoprecipitates. Here, this report focuses on the steps from the immunoprecipitation to the preparation of digested peptides, which are important for researchers who are not experts in proteomics.
