Fig. 7: Crossover formation defects in Brme1^−⁄− spermatocytes.

a Immunostaining of late-pachytene spermatocytes. Two autosomes and sex chromosomes without MLH1 foci are highlighted by white and yellow arrowheads, respectively. Graph: the number of MLH1 foci per spermatocyte associated with the chromosome axis. Red bars: mean value. n shows the analyzed cell number pooled from three mice. Scale bar: 5 μm. b Metaphase I spermatocyte spreads from WT and Brme1^−⁄− males stained with DAPI. Arrowheads: univalent chromosomes. Graph: the number of univalent chromosomes per metaphase I spermatocyte. The mean value is shown as a black bar. n shows the analyzed cell number pooled from three mice. Scale bar: 5 μm. c Testis sections from 8-week-old WT and Brme1^−⁄− males stained with hematoxylin and eosin. Arrowheads: the misaligned univalent chromosomes in metaphase I. Scale bars: 100 μm or 5 μm in the magnified panel. d Brme1^−⁄− testis sections with stage XII seminiferous tubule from 8-week-old male mice stained with TUNEL and DAPI. A TUNEL-positive metaphase I spermatocyte with misaligned univalent chromosomes in the magnified panel. Arrowheads: univalent chromosomes. Scale bars: 15 μm or 5 μm in the magnified panel. e Schematic summary of Brme1^−⁄− male phenotypes. All analyses used two-tailed t tests. ****p < 0.0001. Source data are provided as a Source Data file.