Sadie Wignall Spindle assembly & chromosome segregation during cell division

Research Interests

Proper segregation of chromosomes during mitosis and meiosis depends upon the formation of a bipolar spindle. In most cell types, duplicated centrosomes contribute to spindle assembly by nucleating microtubules and helping to organize the two poles. However, during meiosis in female animals the centrosomes are degraded prior to the meiotic divisions, and therefore oocyte spindles form in their absence. We are interested in understanding how these acentrosomal spindles form, how they are organized, and how they promote proper chromosome partitioning. To address these questions, we combine high-resolution microscopy with genetic, genomic, and biochemical approaches in the nematode C. elegans.

These studies are important since errors in meiotic chromosome segregation result in aneuploidy, a leading cause of miscarriages and birth defects in humans. Female meiosis in particular is highly error prone and this vulnerability has a profound impact on human health; it is estimated that as many as 10-25% of human embryos are chromosomally abnormal, and the vast majority of these defects arise from problems with the oocytes. Our research will yield a better molecular understanding of the mechanisms that promote accurate chromosome segregation during oocyte meiosis, which will shed light on how genomic integrity is maintained during the meiotic divisions.

Selected Publications 

A degron-based strategy reveals new insights into Aurora B function in C. elegans. Divekar NS, Davis-Roca AC, Zhang L, Dernburg AF, and Wignall SM. PLoS Genetics. 2021 May 20;17(5):e1009567.

Dynamic SUMO remodeling drives a series of critical events during the meiotic divisions in C. elegans. Davis-Roca AC, Divekar NS, Ng RK, and Wignall SM. PLoS Genetics. 2018 September 4;14(9):e1007626.

Interplay between microtubule bundling and sorting factors ensures acentriolar spindle stability during C. elegans oocyte meiosis. Mullen TJ and Wignall SM. PLoS Genetics. 2017 September 14;13(9):e1006986.

Caenorhabditis elegans oocytes detect meiotic errors in the absence of canonical end-on kinetochore attachmentsDavis-Roca AC, Muscat CC, and Wignall SM. Journal of Cell Biology. 2017 May 1;216(5):1243-1253.

Kinetochore-independent chromosome segregation driven by lateral microtubule bundles. Muscat CC, Torre-Santiago KM, Tran MV, Powers JA, and Wignall SM. eLife. 2015 May 30;4:e06462.

View all publications by Sarah M. Wignall listed in the National Library of Medicine (PubMed).  Current and former IBiS students in blue.