Fig. 1. borr is required for mitosis in embryonic VNC cells. (A) Schematic representation of the borr locus (black, coding; white, non-coding). The position of the E133 mutation is indicated by an arrowhead. (B,C) Ventral views of stage 12 (B) wild-type and (C) borr mutant embryos; nuclei are stained with Hoechst dye to visualise DNA. (D) Average volumes of wild-type and borr mutant VNC nuclei; numbers of pixels were calculated for each genotype based on outline tracings of 50 nuclei from five different embryos (see Materials and methods).