Fig. 5. DNA breaks, UbcD6 and SUMO are abundant at the late canoe stage. (A-C) Anti-core histone antibody staining together with TUNEL staining on testes squashes of protamine-eGFP flies to visualise DNA breaks in comparison to histone deposition and protamine incorporation during the canoe stage in the same animal. (A) Anti-histone staining is detectable in early canoe stage spermatids (arrow), but not in any later stages. (B) Protamine-eGFP expression is detectable in late canoe stage (arrowhead) and individualising (double arrow) spermatids. (C) DNA breaks marked by TUNEL staining are detectable only at a low level in early canoe stage spermatids (arrow) reaching their highest level in late canoe stage spermatids (arrowhead). During individualisation, DNA breaks are no longer detectable. (D) Anti-HR6A/B antibody staining is detectable in early (arrow) and late (arrowhead) canoe stage spermatid nuclei, but not in later stages. (E) Anti-SUMO staining is detectable in early (arrow) and late (arrowhead) canoe stage spermatid nuclei, but not in later stages. Bars, 5 µm.