Figure 1. A. DAPI stained chromosomes in oocytes of the indicated genotype at diakinesis, the last stage of meiotic prophase; while six pairs of attached homologs are detected in wild-type animals, chromosome structural defects such as fragments (blue arrowhead) or partially decondensed chromosomes (purple arrowhead) are observed in the
me98 mutant. B. Detection of the crossover site marker GFP::COSA-1 in WT (left) and
me98 mutant germ-cells (right). Scale bars on panels A and B represent 2µm. C. Detection of the recombinase RAD-51 in the region of the gonad corresponding to early to middle stages of meiotic prophase in WT (left) and
me98 mutant (right) worms. RAD-51 foci are transiently detected in wild-type animals in early prophase as DNA breaks are formed and repair progresses. In contrast, in
me98 mutants, RAD-51 foci accumulate and remain at high levels. Scale bar represents 10µm. D. Position and nature of the
me98 deletion, located in the second exon of the
rad-54 coding sequence, and its consequences on the encoded protein product. E. Screenshot of genome browser centered on the
rad-54 locus. Positions of the previously described
rad-54 allele,
ok615, and the newly identified
me98 mutation are represented respectively as a yellow and a red bar.