Fig. 6.

EGF receptor tyrosine phosphorylation is decreased by Kv1.3 coexpression. HEK 293 cells were transfected with control, EGFr, or Kv1.3 together with EGFr vectors. A, Two days after transfection, cells were treated with EGF (+) or serum-free medium (−). Cell lysates were prepared, and lysate proteins were separated by SDS-PAGE, transferred to nitrocellulose, and probed with anti-EGFr (top) or anti-phosphotyrosine (bottom) antibody. B, EGFr expression levels and protein phosphotyrosine signals were quantified in eachlane by densitometry. EGFr phosphotyrosine values were normalized to EGFr protein levels (EGFr phosphotyrosine/EGFr protein) and expressed relative to the EGFr (+EGF) lane (n = 6; ***p ≤ 0.005, Student’s t test).