(A) Schematic diagram of the temperature-shift experiment. (B) Expression of TORDN before CW attainment causes arrest of DNA content increase. The PGs (upper panels, outlined) and nuclei of PG cells (lower panels, outlined) in control +Gal80ts and TORDN +Gal80ts animals were labeled for Dib (green) and DNA (white) at indicated stages. Scale bars, 50 μm (upper panels) and 10 μm (lower panels). (C) The C value of PG cells of control +Gal80ts and TORDN +Gal80ts larvae in the continuous 18°C (left), late shift (middle), and early shift (right) experiments at indicated stages. The CW checkpoint in control +Gal80ts is indicated by a dashed line. Average C value of control +Gal80ts at 192 hAEL in continuous 18°C experiment is normalized to 64C. Error bars represent standard errors. 12–18 PGs were analyzed for each group. (D–F) Expression of TORDN before CW attainment causes developmental arrest. Percentages of pupariated control +Gal80ts and TORDN +Gal80ts animals are shown at indicated stages in continuous 18°C (D), late shift (E), and early shift (F) experiments. The CW checkpoint in control +Gal80ts is indicated by a dashed line. 30 animals were tested in each group.