Fig. 1

Structural representation of the RTKs subfamilies. The extracellular ligand binding region differs across RTKs subfamilies, including immunoglobulin (Ig)-like or epidermal growth factor (EGF)-like domains, fibronectin type III repeats, and cysteine/leucine-rich regions. The single-pass transmembrane is linked to the intracellular tyrosine kinase domain (TKD) by the juxtamembrane. When extracellular ligands or a growth factor binds to the extracellular domain, it stimulates dimerization with neighboring RTKs. Dimerization leads to activation of the catalytic site within the TKD. Thus, autophosphorylation occurs as the receptor becomes activated [19]