Sadie Wignall


Ph.D., University of California, Berkeley

Interdisciplinary Biological Sciences Program
Molecular Biosciences

Office Phone: 847.467.0386
Email
Wignall Lab

Research

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, biochemical, and biophysical 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

  1. Wignall, S.M., and Heald, R. (2001).  “Methods for the study of centrosome-independent spindle assembly in Xenopus extracts.”  Methods in Cell Biology.  67: 241-256.  PMID:  11550472.
  2. Chang Y.T., Wignall, S.M., Rosania, G.R., Gray, N.S., Hanson, S.R., Su, A.I., Merlie, J., Moon, H.S., Sangankar, S.B., Perez, O., Heald, R., and Schultz, P.G. (2001).  “Synthesis and biological evaluation of myoseverin derivatives: microtubule assembly inhibitors.”  Journal of Medicinal Chemistry.  44 (26):  4497-4500.  PMID: 11741468
  3. Wignall, S.M., Deehan, R., Maresca, T., and Heald, R. (2003).  “The condensin complex is required for proper spindle assembly and chromosome segregation in Xenopus extracts.”  Journal of Cell Biology. 161(6): 1041-1051.  PMCID: PMC2172990
  4. Wignall, S.M. and Heald, R. (2003).  “The role of chromosome architecture in spindle assembly and anaphase:  The condensed version.”  Cell Cycle.  2(6):  590-591.  PMID: 14512775
  5. Wignall, S.M., Gray, N.S., Chang, Y.T., Juarez, L., Jacob, R., Burlingame, A., Schultz, P.G., and Heald, R. (2004).  “Identification of a novel protein regulating microtubule stability using a chemical approach.”  Chemistry and Biology.  11(1): 135-146.  ** Faculty of 1000 “Recommended” paper.  Was also highlighted in a minireview in the same issue.  PMID: 15113003
  6. Wignall, S.M., and Villeneuve, A. (2009).  “Lateral microtubule bundles promote chromosome alignment during acentrosomal oocyte meiosis.”  Nature Cell Biology.  11(7): 839-844.  ** Faculty of 1000 “Must Read” paper.  Was also highlighted in a minireview in the same issue.  PMCID: PMC2760407
  7. Schvarzstein, M., Wignall, S.M., and Villeneuve, A. (2009).  “Coordinating cohesion, coorientation and congression during meiosis:  Lessons from holocentric chromosomes.”  Genes and Development.  24(3):  219-228.  PMCID: PMC2811823

 

 

Recent Photos

October 27, 2015