Fig. 4.

Dynamics of Kr pattern supports role for the Gt repressor. (A) The blue arrow and blue T-arrow show dual Hb activities on the Kr expression pattern. Repression by Gt (purple T-arrow) is required for maintaining the late Krl pattern. (B) Displayed are the dual-regulation model (dual-B) (Upper) and the same model with Gt repression (Lower). (C) Temporal changes (anterior shift) in the Kr expression pattern during nuclear cleavage cycle 14, from stage 14.4 to 14.6. (D) Blue lines show solutions for stage 14.4 based on the dual-regulation model. Green lines show behavior of these solutions using data from stage 14.6. In the absence of Gt repression, the Kr pattern narrows, which is not in agreement with the observed dynamics of the Kr pattern (see C). (E) In the presence of Gt repression, most solutions from one temporal stage are also valid for the other stage.