- Danlasky, Brennan M;
- Panzica, Michelle T;
- McNally, Karen P;
- Vargas, Elizabeth;
- Bailey, Cynthia;
- Li, Wenzhe;
- Gong, Ting;
- Fishman, Elizabeth S;
- Jiang, Xueer;
- McNally, Francis J
Anaphase chromosome movement is thought to be mediated by pulling forces generated by end-on attachment of microtubules to the outer face of kinetochores. However, it has been suggested that during C. elegans female meiosis, anaphase is mediated by a kinetochore-independent pushing mechanism with microtubules only attached to the inner face of segregating chromosomes. We found that the kinetochore proteins KNL-1 and KNL-3 are required for preanaphase chromosome stretching, suggesting a role in pulling forces. In the absence of KNL-1,3, pairs of homologous chromosomes did not separate and did not move toward a spindle pole. Instead, each homolog pair moved together with the same spindle pole during anaphase B spindle elongation. Two masses of chromatin thus ended up at opposite spindle poles, giving the appearance of successful anaphase.