brc-1 : him-8

GFP::COSA-1 foci were further increased in brc-1; him-8 and brc-1;zim-2 double mutants compared to him-8 and zim-2 single mutants. A total of 62.1% and 86.5% of cells had more than six foci of GFP::COSA-1 in brc-1;him-8 and brc-1;zim-2 double mutants, respectively (p<0.00001; Mann-Whitney U test, comparison with each single mutant).

T07G12.20 : brc-1 : zim-2

GFP::COSA-1 foci were further increased in brc-1; him-8 and brc-1;zim-2 double mutants compared to him-8 and zim-2 single mutants. A total of 62.1% and 86.5% of cells had more than six foci of GFP::COSA-1 in brc-1;him-8 and brc-1;zim-2 double mutants, respectively (p<0.00001; Mann-Whitney U test, comparison with each single mutant).

Interaction involving linc-9

Neither linc-9 nor linc-20 led to increased embryonic lethality compared to wild-type worms (Ishtayeh et al. 2021). To test if the combined linc-9; linc-20 leads to increased embryonic lethality, we scored the percentage of unhatched embryos laid by wild-type vs. linc-9; linc-20 worms. We found no significant change between the strains (Fig. 1B, 0.6%0.3% and 0.6%0.2%, n= 20,19 respectively, p value = 0.4 by the two tailed Mann-Whitney test). Therefore, the combined mutations do not lead to increased embryonic lethality.