The large distance between two loci (green) in rec8− cells indicates decompacted chromosomes.
The role of Rec8, a meiosis-specific cohesin subunit, in chromosome architecture was identified by the authors in a fission yeast screen for meiosis mutants. During meiotic prophase, the yeast nuclei oscillate via microtubule pulling forces that extend chromosomes along the direction of movement. The abnormal movements of chromosomes in rec8− cells suggested an unusual DNA architecture.
The DNA extension that accompanies oscillation offered the group the opportunity to compare chromosome compaction in wild-type and mutant strains. The authors' measurements of the distance between the telomeres and a particular locus revealed long and loose chromosomes in the absences of...
