Upon binding to their respective ligands, typically growth factors, RTKs undergo dimerization or oligomerization. This conformational change activates the receptor's intrinsic kinase activity, leading to the autophosphorylation of tyrosine residues within the cytoplasmic domain. These phosphorylated tyrosines serve as docking sites for a variety of signaling proteins that contain Src homology 2 (SH2) or phosphotyrosine-binding (PTB) domains. These interactions initiate multiple signaling pathways, such as the RAS-MAPK pathway, the PI3K-AKT pathway, and the JAK-STAT pathway.
