{"entity":{"id":"phosphorylation","kind":"term","name":"Phosphorylation","aka":["phosphorylated","phosphorylates","phosphate group","phosphate groups","dephosphorylation","phospho-","phosphorylate"],"tldr":"Attaching a small phosphate tag to a protein, which changes its shape and switches it on or off. It is the cell's main way of passing signals from one protein to the next.","summary":"Kinases add phosphates and phosphatases remove them, so the balance of the two determines whether a signal is flowing. In a growth pathway, each protein is phosphorylated by the one above it and then phosphorylates the one below, which is why a single stuck kinase can light up the entire chain. Detecting phosphorylated proteins (phospho-ERK, phospho-AKT) in tumour tissue is a direct readout of whether a pathway is active and whether a drug has actually switched it off.","asOf":"2026-09-09","wikipedia":"https://en.wikipedia.org/wiki/Protein_phosphorylation","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Protein_phosphorylation"}],"tags":[],"related":["kinase","signalling-pathway","enzyme","growth-signal"],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":["ras-mapk","pi3k-akt-mtor"],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"Biology basics"},"route":"/terms/phosphorylation/","neighbours":{"term":[{"id":"enzyme","kind":"term","name":"Enzyme","route":"/terms/enzyme/"},{"id":"growth-signal","kind":"term","name":"Growth signal","route":"/terms/growth-signal/"},{"id":"kinase","kind":"term","name":"Kinase","route":"/terms/kinase/"},{"id":"signalling-pathway","kind":"term","name":"Signalling pathway","route":"/terms/signalling-pathway/"}],"pathway":[{"id":"pi3k-akt-mtor","kind":"pathway","name":"PI3K / AKT / mTOR","route":"/pathways/pi3k-akt-mtor/"},{"id":"ras-mapk","kind":"pathway","name":"RAS / RAF / MEK / ERK (MAPK)","route":"/pathways/ras-mapk/"}]}}