Part 1 gave an overview on mass spectrometry-based proteomics. Now it’s time to talk about how this strategy can be used to identify peptides with post-translational modifications (PTM) from a complex biological sample.
After sequencing of the human genome was complete, it was time to roll up our sleeves and get started on the daunting task of unraveling the complexity of the proteome. Thus the era of proteomics, the study of the function of all expressed proteins, was born. This task is especially complicated because unlike the human genome, which is largely static in every cell, the proteome is different between say a liver cell and a brain cell, or between a healthy cell and a cancerous cell, or even between an individual cell at the different stages of development. To address this challenge the Human Proteome Project was founded. Its mission is to characterize all human genes by generating a map of the protein based molecular architecture of the body. In this way, it will become a resource to help elucidate the biological and molecular function of genes and facilitate the advanced diagnosis and treatment of disease.
Thinking about lab expenses isn’t as enjoyable as investigating your favorite signaling pathway. However, because research money is hard to come by, it is something that should be considered when picking your reagents for western blotting. It makes sense to keep the quality of your primary antibody in mind, because the success of the entire experiment depends on the antibody being reliable, specific, and sensitive. If the antibody does not perform as expected your experiment may fail . . . and the cost of a failed western blot may be more than you think.
Simplifying proteomics part 1 introduced mass spectrometry-based proteomics for profiling post-translational modifications (PTMs). Part 2 explained how you can go fishing for low abundance PTM peptides from a complex mixture using PTMScan.
If visualization is more your thing, it might be helpful to watch the PTMScan tutorial video to learn more about:
- How PTMScan employs PTM-sequence motif and PTM-specific antibodies to immunoenrich PTM-containing peptides before LC-MS/MS
- How you can use PTMScan services and kits from CST to study PTMs like phosphorylation, acetylation, ubiquitination, methylation, and succinylation
- The PTMScan service workflow from experimental design to data analysis