Figure 7.

The JNK pathway promotes and maintains mitosis until the mitotic-to-endocycle transition point. At the transition, the Notch pathway acts through ttk on the cell cycle components stg, dap, and fzr in follicle cells to stop mitotic cycling and induce endocycling. Notch, which is modulated by Dl, dsh, and sgg, also plays a role in cell differentiation without the involvement of ttk, as shown by its effect on FAS3 expression.