Figure 5. Reduced resection length in MRN hypomorphs.
(A) Schematic of MRN hypomorphs. MRE11 R632* (R632 → stop) mimics human R633* identified in ATLD patients21. Nbs1ΔB produces an 80 kDa protein (red box), mimicking the 657del5 allele found in 95% of NBS patients26.
(B) S1-seq at the hotspot from Figure 1F, from 14.5-dpp mice. Wild type is reproduced from Figure 1F. Two biological replicates were averaged for each of the other genotypes.
(C) Heatmaps (data in 40-bp bins) of S1-seq reads around DSB hotspots.
(D) Genome-average S1-seq at hotspots from 14.5-dpp mice. Wild type is reproduced from Figure 2A. Data are smoothed with a 151-bp Hann window and normalized as described in Figure 4D.
(E–H) Minimal if any changes in RAD51 and DMC1 focus numbers during meiosis in Rad50-L1237F or Rad50-D69Y mice. Representative spreads stained for SYCP3 and DMC1 (E) and RAD51 (G) along with quantification (F, H) are shown. Each dot in the graphs is the focus count from a single nucleus; error bars indicate means ± SD. Results of unpaired t tests are shown for zygonema; differences at the other stages were not statistically significant (P > 0.05).