FIGURE 9.

Kinase activator-receiver hierarchy in ErbB heterodimers. A, schematic diagrams of ErbB heterodimers showing kinase activator-receiver preferences and C-terminal tail phosphorylation patterns (black dots). B, the ErbB2 kinase is the dominant activator when paired with ErbB1 but the dominant receiver when paired with ErbB4. C, due to kinase activator-receiver preferences, ErbB1/ErbB4 heterodimers will result in different patterns of kinase activation and C-terminal tail phosphorylation depending on whether EGF or NRG1β is the stimulating ligand.