Fig. 4. Defects in DSB repair cause a delay in -HIS2AV staining. Wildtype and DSB repair mutant germaria were stained for -HIS2AV (red), DNA (blue) and C(3)G (green). Also shown are the single channels for -HIS2AV and C(3)G staining. (A) A region 3 oocyte from a wild-type female that stains for C(3)G but not for -HIS2AV foci. (B) A region 3 cyst of an okr^WS mutant germarium showing -HIS2AV foci in the oocyte (with extensive C(3)G staining, arrow) and nurse cells (arrowheads). (C) Pro-oocytes in region 2a and 2b cysts of the a spnB^BU mutant germarium. In wildtype, these stages would normally have the maximum number of -H2AX foci for the germarium. Instead, these pro-oocytes have just begun to form foci associated with the SC (arrows). (D) A Region 3 cyst of the spnB^BU mutant shown in (c) that has a large number of foci in the oocyte (arrow) and nurse cells (arrowheads). In this germarium, the previous cyst (region 2b, not shown) was the first one to strongly stain for -HIS2AV and the sixth in the germarium that stained with C(3)G (see C). As in Fig. 3, all images are maximum projections. Bar, 5 µm.