Topoisomerase II immunofluorescence reveals a region of low centromeric staining along the centrosome axis in mouse embryonic fibroblasts

Students: Omoefe Odiase, Shelby Giannamore

Faculty Mentor: Lisa Hua

Biology

College of Science, Technology, and Business

Mitotic antipairing is defined as the spatial segregation of homologous chromosomes along the centrosome axis during metaphase and anaphase of mitosis. This was originally discovered in human umbilical vein endothelial cells (HUVECs), and was also observed in mouse embryonic fibroblast cells (MEFs). Recent findings in our lab revealed a pattern of low centromeric staining along the centrosome axis of HUVECs at metaphase. This region of low centromeric staining may regulate the spatial segregation of homologous pairs. To determine if this pattern is evolutionarily conserved in other mammals and suggests similar mechanisms, we examined topoisomerase II (TopoII), a centromeric protein, in MEFs. Immunofluorescence staining and confocal microscopy of TopoII displayed a region of low centromeric staining along the centrosome axis in MEFs, similar to HUVECs. γ-tubulin was used to visualize the centrosomes, along with a DAPI counterstain to visualize DNA. Our data suggest the pattern of low centromeric staining present in humans may be evolutionarily conserved in mice. Findings from our project will provide a better understanding of important cellular processes that are evolutionarily conserved within mice and humans and hint at a shared mechanism