Nanoluciferase-based complementation assays to monitor activation, modulation and signaling of receptor tyrosine kinases (RTKs)

Receptor tyrosine kinases (RTKs) are transmembrane receptors activated by a wide diversity of growth factors, cytokines or hormones. They ensure multiple roles in cellular processes, including proliferation, differentiation and survival. They are also crucial drivers of development and progression of multiple cancer types, and represent important drug targets. Generally, ligand binding induces dimerization of RTK monomers, which induces auto-/transphosphorylation of tyrosine residues on the intracellular tails leading to the recruitment of adaptor proteins and modifying enzymes to promote and modulate various downstream signaling pathways. This chapter details easy, rapid, sensitive and versatile methods based on split Nanoluciferase complementation technology (NanoBiT) to monitor activation and modulation of two models of RTKs (EGFR and AXL) through the measurement of their dimerization and the recruitment of the adaptor protein Grb2 (SH2 domain-containing growth factor receptor-bound protein 2) and the receptor-modifying enzyme, the ubiquitin ligase Cbl.