Figure 8.

DNA replication in mitotic cyclin mutants. Embryos at the appropriate developmental stages were pulse labeled with BrdU followed by double labeling with anti-BrdU antibodies (A–F) and anti-β-galactosidase antibodies for genotype determination (not shown). Control embryos are shown in A, C, E and Cyclin A⁻ Cyclin B⁻ Cyclin B3⁻ triple mutants (Df(2R)59AB; CycA^C8LR1 CycB3¹) in B, D, F. (A,B) stage 9; (C,D) stage 10; (E,F) stage 14. Arrows in D indicate rare pairs of BrdU-positive nuclei in the epidermis of triple mutants at the stage of S phase 16. (cns) Central nervous system; (mg) midgut. For further explanations, see text.