Caenorhabditis elegans spermatocytes can segregate achiasmate homologous chromosomes apart at higher than random frequency during meiosis I.

ABSTRACT: Chromosome segregation errors during meiosis are the leading cause of aneuploidy. Faithful chromosome segregation during meiosis in most eukaryotes requires a crossover which provides a physical attachment holding homologs together in a "bivalent." Crossovers are critical for homologs to be properly aligned and partitioned in the first meiotic division. Without a crossover, individual homologs (univalents) might segregate randomly, resulting in aneuploid progeny. However, Caenorhabditis elegans zim-2 mutants, which have crossover defects on chromosome V, have fewer dead embryos than that expected from random segregation. This deviation from random segregation is more pronounced in zim-2 males than that in females. We found three phenomena that can explain this apparent discrepancy. First,

SUBMITTER: Gong T 

PROVIDER: S-EPMC10319977 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature