Fig. 7. The proposed role of GL3 and EGL3 in epidermal cell specification. In the N cell position, there is a relatively high level of WER relative to CPC, which enables a WER-GL3/EGL3 complex to form and promote GL2 and CPC transcription. In the H position, a relatively high level of CPC leads predominantly to formation of the inactive CPC-GL3/EGL3 complex. Proteins shown in white ovals are at low concentrations. See text for detailed discussion.