Fig. 3. Regulatory interactions during lens formation in the head surface ectoderm and lens. (A) Schematic depicting selected transcription factors important for lens formation that are expressed in the mouse head surface ectoderm. These interactions help specify the activation of Foxe3 in the lens placode. (B) Roles of Foxe3 in the development and differentiation of the lens (orange). Feedback loops are not depicted here and arrows between genes do not necessarily imply direct regulatory interactions.