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Fig. 8
A: 1A-5B: spo11 -/- nuclear surface spreads stained for Sycp3 (green), Sycp1 (blue), telomeres (Tel; magenta), and DNA (DAPI, blue). 1C-5C: Magnified (Mag) images are from regions indicated by white boxes in the panels above. Telomere associations are seen at all stages (arrowheads); Short stretches of Sycp1 are seen in some mutant cells (short arrows). Scale bar = 5μm. B: Numbers of engaged telomeres in WT vs. spo11 -/-cells. The mutant cells were categorized based on similarity to WT Sycp3 loading extent. Post-LZ refers to all cells that were classified as pre-pachytene or pachytene in WT and equivalent cells in spo11 mutants. The data was pooled from two experiments done on different days (set 1, orange circles; set 2, green diamonds). P values were acquired using unpaired t test with Welch’s correction. For * p ≤ 0.0314, and for **** p < 0.0001. While WT telomere engagements are reduced at later stages, the telomere engagements in spo11-/- are maintained. C: Dot plot of BAC distance measurements in WT and spo11 -/- males (in μm). In the WT during the early stages when the average Sycp3 lines are short (< 2 μm), the BAC signals are unpaired; As meiosis progresses and the Sycp3 lines elongate (> 2 μm), the BAC signals exhibit pairing (p = 0.0004, unpaired t test with Welch’s correction). In the spo11 -/- males the BAC signals remain unpaired even with extended Sycp3 axes.