Figure 3

ERBB receptor regulated G1/S transition network derived from published data. ERBB receptors are functional (i.e. able to transmit signal to downstream proteins) only when they form heterodimers, except for ERBB1, which is also functional as a homodimer. The number associated with each arrow indicates the reference from which the corresponding interaction was extracted (a list of these references is provided in the Additional file 1, Table 1). Normal arrows denote positive regulations, whereas blunt arrows denote negative regulations. These interactions correspond to transcriptional regulations, post-transcriptional modifications, or physical interaction. EGF constitutes the input and pRB protein represents the output of the network.