In 1996, Peter Klein of the University of Pennsylvania discovered that one of lithium's biological activities was inhibiting GSK - 3, an enzyme that modifies other proteins by attaching phosphate molecules, a process called phosphorylation. (sciencedaily.com)
But mutated or dysfunctional Rb is associated with several major cancers and Cyclin D has long been described as an oncogene that promotes cancer because it was believed to inactivate the Rb tumor suppressor function through a process called phosphorylation, which involves phosphate molecules being added to proteins, essentially turning them on or off. (sciencedaily.com)
The idea is that adding a phosphate group, a process called phosphorylation, to the protein Runx2, changes its structure to activate specific genes in both bone and prostate cancer cells — but with vastly different results. (sciencedaily.com)