Fig. 5: MDC1 is dispensable for NBS1’s function at meiotic prophase.
From: NBS1 is required for SPO11-linked DNA double-strand break repair in male meiosis
a Immunofluorescence staining analyses of MDC1 and NBS1 in Mdc1+/+ and Mdc1−/− MEFs after treatments of 10 µM bleomycin for 6 h or 5 µM etoposide for 2 h. γH2AX marks DNA damage sites. Scale bar, 10 µm. b Immunofluorescence staining of SYCP3 and γH2AX were used for analyses of stages of meiotic prophase in spermatocytes from Mdc1−/− mice. Scale bar, 5 µm. Surface spreads of zygotene spermatocytes from Mdc1+/+ and Mdc1−/− mice were incubated with antibodies against RAD51 (c), DMC1 (d), RPA2 (e), and MEIOB (f). Scale bar, 5 µm. g Localization of MDC1 in surface spreads of pachytene spermatocytes from Mdc1+/+ and Mdc1−/− mice. Scale bar, 5 µm. h Localization of endogenous NBS1 in surface spreads of pachytene spermatocytes from Mdc1+/+ and Mdc1−/− mice. Scale bar, 5 µm. Cartoons depicting proteins (red) localized on chromosome loops and axes (green) are shown on the right. Arrows mark chromosome axes and arrowheads mark chromosome loops. i Localization of endogenous NBS1 in surface spreads of pachytene spermatocytes from H2ax+/+ and H2ax−/− mice. Scale bar, 5 µm. Cartoons depicting proteins (red) localized on chromosome loops and axes (green) are shown on the right. Arrows mark chromosome axes and arrowheads mark chromosome loops.
