top-2(it7ts) chromosome-segregation defects are not dependent on SPO-11-induced DSBs. Young adult spo-11(ok79)/nT1; top-2(it7ts) or spo-11(ok79); top-2(it7ts) males (16 hr post-L3) were incubated at either 15 or 24° for 4 hr, the germ lines dissected, fixed, and stained with DAPI. Chromosome segregation was monitored by fluorescence microscopy. Images are from the spermatogenesis condensation and meiotic division zones. Yellow triangles indicate examples of chromatin bridges and incompletely separated chromosomes. The number of germ lines with chromosome-segregation defects at 15°: spo-11(ok79)/nT1; top-2(it7ts), 0 of 7; spo-11(ok79); top-2(it7ts), 5 of 10. The number of germ lines with chromosome-segregation defects at 24°: spo-11(ok79)/nT1; top-2(it7ts), 16 of 17; spo-11(ok79); top-2(it7ts), 14 of 14. Bar, 5 μm.