Fig. 6. The myt1 mutant over-proliferation defects are due to a failure of Cdk1 inhibitory phosphorylation. (A,D) PH3 (red) staining shows that heat-shocked Cdk1AF testes (D) have extra dividing cells, compared with controls (A). (B,E) BamC (green) and PH3 (red) staining identifies dividing secondary spermatogonia. In the heat-shocked Cdk1AF testes, a 16-cell cyst undergoing ectopic mitosis (E, white arrow) is shown, not seen in the controls (B). (C,F) Eya (green) staining to label somatic cyst cells shows that heat-shocked Cdk1AF testes have more cyst cells (F) than do controls (C). Scale bar: 40 µm for A,D; 8 µm for B,E; 20 µm for C,F.