Cell signaling RTK

Define enzyme coupled receptors (+Typical structure)

• Large, heterogeneous family of transmembrane proteins that function as enzymes

• “Single-pass” membrane proteins (typically):

  • Ligand-binding domain on the extracellular side of the PM.

  • Catalytic site on the cytoplasmic side of the PM.

• Typically, act as protein kinases that phosphorylate specific sets of proteins in the target cell.

• Receptor tyrosine kinases (RTKs) are most common class of these proteins

Examples of extracellular signal proteins that act via RTKs

• EGF - epidermal growth factor

• NGF - Nerve growth factor

• PDGF - platelet-derived growth factor

• FGF - fibroblast growth factor

• VEGF - vascular endothelial growth factor

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