Figure 8
From: The Pax gene eyegone facilitates repression of eye development in Tribolium
A model of gena development and evolution in Tribolium. In the ancestral state, retinal differentiation progresses at equal rate and distance along the anterior edge of the developing eye. In Tribolium, retinal differentiation is suppressed in the anterior midline area of the developing eye by an unknown signal (factor X) produced in the posteriorly expanding gena. The results of this study further show that eyg is essential for the competence of cells in the contact zone between retina (blue field) and gena (brown field) to respond to factor X.