Loss of BRC-1 in CO-defective mutants differently influences RAD-51 loading in presence or absence of SC.

(A) Left: quantification of DAPI-stained bodies in diakinesis nuclei in different genotypes. Number of diakinesis nuclei scored: WT, 44; brc-1 brd-1, 46; cosa-1, 42; cosa-1 brc-1 brd-1, 48; msh-5, 43; brc-1 brd-1; msh-5, 55; syp-2, 31; brc-1 brd-1; syp-2, 79. Right: representative images of DAPI-stained diakinesis nuclei in the genotypes quantified. Scale bar, 3 μm. (B) Top. Quantification of RAD-51 foci per nucleus throughout the germline. Each gonad was divided into seven equal zones and RAD-51 foci were counted in each nucleus. Data show the average of at least three gonads for each genotype. Number of nuclei scored from zone 1 to zone 7 in different genetic backgrounds: WT– 154, 226, 189, 157, 113, 95, 92; brc-1 brd-1–173, 189, 186, 156, 136, 125, 72; cosa-1–162, 225, 179, 165, 142, 107, 124; cosa-1 brc-1 brd-1–347, 335, 285, 274, 228, 175, 149; msh-5–205, 179, 120, 115, 94, 74, 66; brc-1 brd-1; msh-5–211, 237, 197, 194, 171, 114, 92; syp-2–244, 265, 241, 233, 190, 131, 118; brc-1 brd-1; syp-2–226, 305, 275, 297, 254, 161, 147. Error bars show S.E.M. Bottom. Representative examples of whole-mount gonads stained with DAPI and RAD-51, showing extended RAD-51 accumulation in both cosa-1 brc-1 brd-1 and brc-1 brd-1; msh-5 mutants, whereas dramatic reduction of RAD-51 is observed in brc-1 brd-1; syp-2 mutants. Green lines indicate regions affected. Scale bars, 30 μm.