Fig. 2: Activation of the replication checkpoint upon POLA2 depletion.

A, B Confocal images of the wing pouch of ap > GFP (A) and ap > GFP + POLA2-i (B) discs labeled with anti-pH2Av and EdU. In the merge, DAPI, GFP, pH2Av, and EdU are shown in blue, green, red, and grayscale, respectively. Scale bars, 10 µm. C Confocal image of the wing pouch of an ap > POLA2-i disc carrying an RPA1-GFP sensor and labeled with anti-pH2Av. A magnification of the dorsal compartment is shown in C'. In the merge, DAPI, RPA1-GFP, and pH2Av are shown in blue, green, and red, respectively. Scale bars, 10 µm. D–F Confocal images of the wing pouch of ap > GFP (D) and ap > GFP+Brca2-i (E) discs 4 h after irradiation and of a non-irradiated ap > GFP + POLA2-i (F) disc stained with anti-pH2Av and anti-Rad51. The DV boundary is outlined in yellow. The Rad51 maxima panel exhibits the selection of Rad51 foci in the dorsal compartment. In the merge, DAPI, GFP, pH2Av, and Rad51 are shown in blue, green, red, and grayscale, respectively. Scale bars, 10 µm. G Quantification of the Rad51 foci per area in the dorsal compartment of the genotypes indicated in D-F (n = 20, 15, 30). Data shown are mean ± SD. Statistical analyses were performed using a two-tailed Mann–Whitney test (for the ap > GFP vs ap > GFP+Brca2-i comparison) and a two-tailed unpaired t-test with Welch’s correction (for the ap > GFP vs ap > GFP + POLA2-i comparison).