Figure 1

Diagrams of the functional domains of Pax6 and of the alterations in the mutant mouse lines used in this study. Pax6^Aey18 mutants lack exons 5a and 6 of the paired domain. Pax6^4Neu and Pax6^14Neu mutants carry point mutations at adjacent sites in the third helix of the homeodomain which abolish binding of that domain to its classical P3 DNA target sequence. Pax6^Sey-Neu lack the transactivation domain. (PD = paired domain; HD = homeodomain; TA = transactivating domain; PAI/RED = N- and C-terminal DNA-binding sub-domains of the PD).