Growth factor–dependent ErbB vesicular dynamics couple receptor signaling to spatially and functionally distinct Erk pools
The related growth factors EGF and HRG signal through related receptors to the same effector, the kinase Erk, yet can elicit the divergent responses of proliferation and migration. The group of Prof. Philippe Bastiaens analyzed how EGF and HRG induced these responses through different patterns of receptor trafficking to spatially distinct pools of Erk. Whereas HRG stimulated receptors and a pool of Erk localized to the plasma membrane to induce migration, EGF triggered receptor internalization and transient activation of a cytoplasmic pool of Erk, resulting in proliferation. However, a low concentration of EGF resulted in receptor recycling to the plasma membrane and migratory responses. Thus, the cellular outcome of growth factor stimulation is dictated by ligand- and concentration-dependent receptor trafficking patterns to different subcellular pools of Erk.