Phosphorylation

Phosphorylation designates the enzymatic addition of phosphate groups to proteins, lipids, or other molecules, representing one of the most important post-translational modifications regulating cellular signalling, enzyme activity, protein localisation, and protein-protein interactions. Protein phosphorylation typically occurs on serine, threonine, or tyrosine residues mediated by kinases, while phosphatases reverse the modification, creating dynamic regulatory switches.

The biopharmaceutical industry extensively targets phosphorylation pathways for therapeutic intervention, particularly in oncology where dysregulated kinase signalling drives uncontrolled proliferation, survival, and metastasis. Kinase inhibitors represent one of the most successful targeted therapy classes, with drugs inhibiting EGFR, BRAF, MEK, or PI3K pathways demonstrating dramatic efficacy in genetically defined cancers. Phosphorylation biomarkers support drug development by confirming target engagement and pathway inhibition, with assays measuring phosphorylated proteins used in preclinical studies and clinical trials. Beyond cancer, phosphorylation regulates inflammatory signalling, neuronal function, and metabolic pathways. Analytical methods including Western blotting, phospho-specific flow cytometry, and mass spectrometry-based phosphoproteomics enable comprehensive phosphorylation profiling across complex biological systems.