Figure 2

G1 arrest requires Dpp and Hh signal reception. All figures show Cyclin B protein (green) in mutant clones and neighboring wild type regions spanning the morphogenetic furrow, with anterior to the left. Homozygous cells are identified by the absence of β-galactosidase (magenta). (A) tkv⁴; (B)Mad¹²; (C) Mad^1-2; (D) tkv⁴in tkv +/+ M background; (E) Mad¹²in Mad +/+ M background; (F) tkv⁴ci⁹⁴in tkv ci +/+ + M background; (G) Mad¹²ci⁹⁴in Mad ci +/+ + M background; (H) smo Mad^1-2in smo Mad +/+ + M background; (I) smo³tkv⁸in smo tkv +/+ + M background; (J) smo³Mad¹²in smo Mad +/+ + M background. Many of these genotypes have also been examined with anti-pH3 labelling to assess mitotic activity, and BrdU incorporation studies to measure S-phase DNA synthesis, confirming the results obtained with CycB labeling in all cases [26](data not shown).