RTK families

Of the more than
twenty different RTK families, five examples are
selected here: the epidermal growth factor receptor
(EGFR); insulin receptor (IR); fibroblast
growth factor receptor (FGFR) types 1, 2, and 3;
platelet-derived growth factor (PDGFR); and
RET (rearranged during transformation).
These receptors share structural features, although
they differ in function. All have a single
transmembrane domain and an intracellular tyrosine
kinase domain of slightly varied size. The
extracellular domains consist of evolutionarily
conserved motifs: cystein-rich regions, immunoglobulin
(Ig)-like domains, fibronectin repeats
in the tyrosine kinase with Ig and the EGF.
RTK mutations cause a group of important
human diseases and malformation syndromes.
The phenotypes of the mutations differ according
to the particular type of RTK involved and
the type of mutation.