Selected reaction monitoring for quantitative proteomics: a tutorial

Area of Science:

• Proteomics
• Systems Biology
• Analytical Chemistry

Background:

• Systems biology requires consistent protein identification and precise quantification across samples, a challenge for current proteomics methods.
• Shotgun proteomics excels at discovery but has limitations in quantifying low-abundance proteins.

Purpose of the Study:

• To explain the application of Selected Reaction Monitoring (SRM) for quantitative proteomics.
• To detail the selection of proteotypic peptides and optimization/validation of transitions for SRM assays.
• To discuss factors influencing sensitivity, accuracy, and normalization in SRM experiments.

Main Methods:

• Utilizes a triple quadrupole mass spectrometer to monitor specific precursor and fragment ion transitions over time.
• Employs retention time alignment with a series of transitions to create definitive peptide assays.
• Focuses on the selection and validation of proteotypic peptides for targeted quantification.

Main Results:

• SRM provides a complementary approach to shotgun proteomics, enabling reliable quantification of low-abundance analytes.
• A series of precursor/fragment ion transitions combined with retention time serves as a definitive assay.
• The tutorial covers essential aspects from peptide selection to assay validation and data normalization.

Conclusions:

• Selected Reaction Monitoring (SRM) is a powerful technique for precise and reliable quantification in complex biological mixtures.
• SRM effectively addresses the need for consistent protein quantification in systems biology.
• This tutorial provides a comprehensive guide for applying SRM in quantitative proteomics.