Fig. 3: BRME1 is a meiotic DSB-associating protein.

a Immunostaining of WT spermatocytes. Graph: the number of BRME1 foci associated with the chromosome axes. Red bars: mean value. n shows the analyzed spermatocyte number pooled from three mice. b Immunostaining of WT spermatocytes. 79%, 81%, and 89% of the BRME1 foci stained positive for MEILB2 and 83%, 85%, and 86% of the MEILB2 foci stained positive for BRME1 at the leptotene (five cells), zygotene (nine cells), and early-pachytene (seven cells) stages, respectively. Cells were pooled from two mice. c Schematic of BRME1 truncations. F (a.a. 1–605), N (a.a. 1–518), C (a.a. 519–605), and MBD (a.a. 519–600). d Immunostaining of WT spermatocytes in zygotene (Z; top) or early-pachytene (EP; bottom) expressing ^GFP-BRME1 truncations shown in c. e The number of ^GFP-BRME1 foci associated with the chromosome axes. Red bars: mean value. n shows the analyzed spermatocyte number pooled from three electroporated mice for each transgene. f Immunostaining of zygotene spermatocytes. Intensified BRME1 signals in Meilb2^−⁄− are shown in Supplementary Fig. 3d. Graph: the number of BRME1 (left) or RPA2 (right) foci associated with the chromosome axes. Red bars: mean value. n shows the analyzed spermatocyte number pooled from two mice for each genotype. g, h Immunostaining of zygotene spermatocytes. MEILB2 g and BRME1 h are stained. Leptotene (L), zygotene (Z), early-pachytene (EP), late-pachytene (LP), diplotene (D). All analyses were with two-tailed t tests. ns, not significant. Scale bars: 5 μm or 1 μm (magnified panel). Source data are provided as a Source Data file.