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Published on: August 2, 2018
A Multipathway Phosphopeptide Standard for Rapid Phosphoproteomics Assay Development
Brian C Searle1, Allis Chien2, Antonius Koller3
1Department of Biomedical Informatics, The Ohio State University, Columbus, Ohio, USA; Pelotonia Institute for Immuno-Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA.
A new phosphopeptide standard mixture helps researchers standardize phosphoproteomics across labs. Using this standard allows for reproducible, harmonized data, improving the reliability of mass spectrometry-based signaling pathway analysis.
Area of Science:
- Proteomics
- Biochemistry
- Molecular Biology
Background:
- Phosphopeptide analysis is crucial for understanding cell signaling.
- Recent advances offer accessible enrichment strategies and free software for phosphoproteomics.
- Standardization is needed for reproducible phosphoproteomic profiling across different laboratories.
Purpose of the Study:
- To develop and characterize a multipathway phosphopeptide standard mixture.
- To assess the utility of this standard for harmonizing phosphoproteomic data across multiple laboratories.
- To enable rapid assay development for researchers studying signaling networks.
Main Methods:
- A mixture of 131 heavy-labeled phosphopeptides was created, covering seven key signaling networks.
- The standard was spiked into HeLa cell tryptic digests stimulated with growth factors.
- Phosphoproteomic profiling was performed using data-independent acquisition in five independent laboratories.
Main Results:
- Reporting measurements as ratios to the standard yielded reproducible and harmonized datasets across labs.
- Intensity measurements showed lower consistency between laboratories, even after normalization.
- The phosphopeptide standard acted as a quantitative yardstick, enabling cross-laboratory data comparison.
Conclusions:
- Biologically relevant phosphopeptide standards are essential for reproducible phosphoproteomics.
- Standardized quantitative measurements improve data consistency and enable larger-scale collaborative research.
- This phosphopeptide mixture facilitates robust assay development and cross-laboratory validation.
