LiP-MS Limited Proteolysis - Mass Spectrometry
LiP-MS is a label-free, high-throughput, in situ conformational analysis core technology in structural proteomics. Through limited proteolysis by proteinase K combined with high-resolution MS quantification, it achieves precise characterization of protein conformational dynamics and interactions in complex systems.
- No chemical modification or protein purification required — preserves physiological conformation in situ
- Single-run identification of ~3,500 proteins / ~40,000 peptides — 3–5× coverage improvement over traditional methods
- Conformational response detection limit down to nM level — sample consumption only 1/10 of labeling methods
- Reproducibility: biological replicate R² > 0.95, technical replicate R² > 0.98
CETSA Cellular Thermal Shift Assay
CETSA is based on the principle that ligand binding alters protein thermal stability, enabling direct detection of target protein-ligand interactions inside living cells. It overcomes limitations of traditional interaction techniques that depend on purified proteins outside physiological environments.
- Classic CETSA (Western Blot detection): for known target validation
- MS-CETSA (whole-proteome detection): for unknown target screening & off-target analysis
- ΔTm > 2 °C indicates specific binding — supports concentration-dependency validation