Schematic diagrams for hypothesized HER receptor interaction patterns. These diagrams illustrate the EGFR-HER3 interaction patterns that have been reported in the literature. (A) EGFR and HER3 receptors interact directly, i.e., HER2 is not required; (B) HER2 is the explicit facilitator of a lateral interaction; and (C) EGFR and HER3 do not interact with each other but both of them independently interact with HER2. EGFR can also activate itself by forming homodimers.
Zhang et al. BMC Cell Biology 2009 10:78 doi:10.1186/1471-2121-10-78