Signal transduction by the receptor tyrosine kinase Ret.

Ret is the receptor for glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN). Defects in this receptor underlie several genetic syndromes. The receptor is a transmembrane tyrosine kinase which transduces Ret-mediated signaling to a variety of signaling pathways, most notably the Ras signaling pathway and the phosphatidylinositol-3 kinase pathway. These pathways are activated through the interaction of adaptor proteins to tyrosine phosphorylated receptor. The ultimate biological effects, depending on the cell type, include morphological changes in the cytoskeleton, cell scattering, proliferation, and differentiation.