We have adapted a recently developed quantitative proteomics based approach to measure protein solubility following a lysate centrifugation assay to determine the proportion of a protein in distinct subpopulations in a proteome-wide manner (Sridharan et al., 2019). Further, by combining the solubility measurements with phosphoproteomics (Potel et al., 2021), we have quantitatively mapped phosphorylation sites enriched in the different protein subpopulations.