Figure 1. A. Schematic of six chromosomes in wildtype worms drawn to scale, as well as in backgrounds with chromosomal rearrangements, mIn1/+,
hIn1/+, meDf2 and mnT12. Arrows indicate the right end of the chromosomes and dashed gray lines indicate portions of chromosomes inverted in mIn1/+ and
hIn1/+. meDf2 is a terminal or near-terminal deletion of the left portion of the X chromosome, with some ambiguity regarding its breakpoint (shaded portion), and mnT12 is a fusion between chromosomes X and IV. Representative images of wildtype (B), mIn1/+ (C), and
hIn1/+ (D) hermaphrodite germlines stained with DAPI (top) and antibodies against DSB-1 (middle) and PCH-2 (bottom). E. Fraction of total meiotic nuclei in the germline stained with DSB-1 and PCH-2 in wildtype, mIn1/+, and
hIn1/+ germlines (n=5 per genotype). No significant difference (ns) is observed between wildtype, mIn1/+, and
hIn1/+. Representative images of meDf2 (F) and mnT12 hermaphrodite germlines (G) stained with DAPI (top) and antibodies against DSB-1 (middle) and PCH-2 (bottom). H. Fraction of total meiotic nuclei in the germline stained with DSB-1 and PCH-2 in wildtype, meDf2, and mnT12 germlines (n=4 for wildtype and n=5 for meDf2 and mnT12). I. Representative images of meiotic nuclei stained with DAPI (magenta) and GFP::COSA-1 (green). The nucleus in mnT12 has six GFP::COSA-1 foci while the nucleus in mnT12;
pch-2 has five. Scale bar indicates 2 microns. J. Histogram representing the fraction of meiotic nuclei with four, five, six, and seven GFP::COSA-1 foci in mnT12 (n=483 nuclei) and mnT12;
pch-2 mutants (n=446 nuclei). In all graphs, error bars indicate standard deviation and ** indicates a p value < 0.001. Unless otherwise stated, scale bars in images indicate 8 microns.