Figure 9.

Cyclin-dependent kinase 1 (Cdk1/cdc2) is expressed in imaginal but not in larval tissues. The cluster analysis for Cdk1 is shown for 41 pairwise comparisons with each box representing one experiment. All the disc-to-disc comparisons (see text) group to the left and display ratios of the intensities close to 1, as indicated by the dark shades of red and green (color coding as in Figure 3). The in situ hybridization to the various imaginal discs confirmed that Cdk1 is expressed in all discs. Cluster analysis of the comparisons of discs (labeled in green) and larval tissues (red) showed a strong induction in imaginal discs (represented by the intense green staining). This finding is confirmed by previous descriptions that Cdk1 is downregulated in endoreplicated tissues and by the lack of signal after in situ hybridization (FB, GUT and SG). The wing disc (W) to brain/optic lobe (OL) comparisons revealed less induction of Cdk1 in the wing disc as indicated by the darker shades of green. This is in good agreement with in situ hybridization data that showed some expression, particularly in the proliferation zones of the optic lobe, but no signal in most parts of the brain. Abbreviations as in Figure 8.