Cell Division and Reproduction

Group leader

Worldwide it is estimated that 15% of couples have problems conceiving. One potential explanation for the recent decline in human fertility is a poor quality of germ cells or gametes (spermatozoids and oocytes). A major challenge for biologists is to understand the cause of this reduction in gametes quality.

A likely primary cause for poor germ cell quality is aneuploidy (a wrong number of chromosomes in the cell). Indeed, the vast majority of embryos formed from aneuploid gametes are non-viable and lead to spontaneous abortion. A few aneuploid embryos are viable, but lead to lifelong conditions such as Trisomy 21/Down Syndrome (due to an extra chromosome 21) with a prevalence of ~1:1000 live births in the general population. Aneuploidy usually arises from errors in the process of chromosome segregation during cell division.

Our project aims at understanding the mechanisms that promote production of oocytes with a correct number of chromosomes, which is essential for the generation of viable and normal embryos and thus for successful reproduction. We use a multidisciplinary approach that combines genetics, cell biology, cutting edge microscopy technics and the use of the powerful Caenorhabditis elegans model system.

Dumont

Montage illustrating the different steps of chromosome segregation during the first meiotic division of the C. elegans oocyte.
In C. elegans, a microtubule-based spindle (green) assembles during meiotic division and promotes chromosome (red) alignment on a metaphase plate (1). Spindle poles then shrink around chromosomes (2). Finally, during anaphase, microtubules concentrate between the separating chromosomes and ‘push’ them toward the two future daughter cells (3).

Sélection of publications

Laband, K., Le Borgne, R., Edwards, F., Stefanutti, M., Canman, J.C., Verbavatz, J-M. & Dumont, J.
Chromosome segregation occurs by microtubule pushing in oocytes
Nat Comm, Nov 14;8(1):1499, (2017).
Abstract

Gigant, E.*, Stefanutti, M.*, Laband, K., Gluszek-Kustusz, A., Edwards, F., Maton, G., Lacroix, B., Canman, J.C., Welburn, J. & Dumont, J.
Inhibition of ectopic microtubule assembly by the kinesin-13 KLP-7MCAK prevents chromosome segregation and cytokinesis defects in oocytes
Development, 144(9):1674-1686 (2017).
Abstract

Joly, N., Martino, L., Gigant, E., Dumont, J., & Pintard, L.
Microtubule-severing activity of AAA-ATPase Katanin is essential for female meiotic spindle assembly
Development, 143(19):3604-3614 (2016).
Abstract

Hattersley, N., Cheerambathur, D., Moyle, M., Stefanutti, M., Richardson, A., Lee, K.Y., Dumont, J., Oegema, K., & Desai, A.
A Nucleoporin Docks Protein Phosphatase 1 to Direct Meiotic Chromosome Segregation and Nuclear Assembly
Dev. Cell, 35, (5):463-477 (2016).
Abstract

Maton, G.*, Edwards, F.*, Lacroix, B., Stefanutti, M., Laband, K., Lieury, T., Kim, T., Espeut, J., Canman, J.C., & Dumont, J.
Kinetochore components are required for central spindle assembly
Nat Cell Biol 17(5):697-705 (2015). (*co-first authors)
Abstract

Last modified 17 November 2017

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