Biochemical characterization of mutant EGF receptors expressed in the hemopoietic cell line BaF/3

Abstract

The Epidemal Growth Factor (EGF) receptor appears to require a fully active tyrosine kinase domain to transmit mitogenic signals. However, waved-2 mice carrying a mutation in the α-helix C of their EGF-R, which abolishes tyrosine kinase activity, only display a mild phenotype and are fully viable. This suggests that the mutant EGF-R signals through heterodimerization with endogenous, kinase active members of the EGF-R family such as ErbB-2 or ErbB-4. We have examined the biochemistry of EGF-Rs carrying mutations in the α-helix C of the human EGF-R (V741G and Y740F), in the ATP binding site (K721R) and at the C-terminus (CT957), by expression in BaF/3 cells which are devoid of EGF-R family me..