Vincent Archambault and his team are studying the molecular mechanisms that regulate the cell division cycle, particularly mitosis. Disruptions in this process can contribute to the emergence and abnormal proliferation of cancer cells.

Research topic

Cell division is essential for the development, survival, and reproduction of all living species. At each cycle, cellular components, including chromosomes, must be synthesized and segregated accurately when one cell becomes two cells. This process requires the coordination of several intracellular events by a network of enzymes that appeared early in the evolution of eukaryotes. Defects in the functions of these enzymes can lead to chromosome segregation errors or excessive cell divisions, which promote the development of cancer.

To understand the molecular mechanisms of cell division, the Archambault laboratory uses Drosophila as a model organism, as well as healthy and cancerous human cells in culture. Their multidisciplinary approach combines genetics, molecular biology, biochemistry, chemical biology, and various types of microscopy, including video microscopy. New mechanisms identified in Drosophila are generally conserved in humans.

The team is particularly interested in the spatiotemporal mechanisms that control the entry and exit of mitosis. When a cell enters mitosis, it condenses its chromosomes, breaks down its nuclear envelope, and assembles a mitotic spindle to which the chromosomes attach. These events require the coordinated activities of several kinase enzymes. At the end of mitosis, the chromosomes are separated and the two emerging cells reconstitute a nuclear envelope, decondense their chromosomes, dismantle the spindle, and separate by cytokinesis. These events require other enzymes, including phosphatases. To modify their substrates in an orderly fashion, mitotic enzymes communicate with each other and undergo marked changes in localization during cell division.

Research objectives

The Archambault laboratory aims to identify the most crucial substrates of key mitotic enzymes and determine how changes in substrates translate into physical changes during cell division. Another objective is to understand how mitotic enzymes are themselves regulated in time and space within the cell, and how this regulation serves their functions. Finally, the team is working to better understand the cellular and physiological consequences of mitotic defects in the context of cancer development.

This fundamental knowledge of cell biology can serve as a basis for the development of new treatments that interfere with cancer cell division or exploit the tendency of cancer cells to divide abnormally.