EMBO Gold Medal Lecture

In shape to divide: coordination of cell polarization and division

Cell polarization is a fundamental property that underlies many cellular functions. We study the spatial organization of cells and how this organization controls cell growth and division. We use a simple unicellular eukaryotic model, the fission yeast Schizosaccharomyces pombe, which exhibits a regular rod-shape. Its cellular form is established by microtubules, which mark the extremities of the cells as zones of polarized growth and ensure division at the cell middle. Microtubules deposit proteins required for cell polarization at cell tips; these factors promote the local activation of the widely conserved small GTPase Cdc42. In turn, Cdc42 promotes actin organization and vesicle trafficking to drive polarized cell growth. Yeast cells then use their simple geometry to orchestrate the position and timing of cell division. Positive signals provided by the nucleus at the cell middle, as well as negative signals from cell extremities combine to position division medially, giving rise to equally-sized daughter cells. I will present our recent work on the regulation of the Cdc42 polarization machinery, and discuss how spatial concentration gradients of a protein kinase, Pom1, may serve to link growth to cell division.

Biography

Sophie Martin studied Biology at the University of Lausanne and earned her Diploma in 1999 for her study of chromatin organization in the laboratory of Susan Gasser. She received her PhD in 2003 from the University of Cambridge for her work in the laboratory of Daniel St Johnston on the molecular mechanisms of cell polarization and mRNA localization in Drosophila. She obtained postdoctoral training in Fred Chang’s laboratory at Columbia University in New York, studying cell polarization and the cytoskeleton in the fission yeast. Since 2007, she leads her research group, first as a Swiss National Science Foundation professor and from 2010 as associate professor, at the University of Lausanne, where she studies how the spatial organization of the cell underlies its growth, division and differentiation. In 2009, she was elected an EMBO Young Investigator, in 2012 she received the WICB Junior Award from the American Society for Cell Biology, and in 2014 the Friedrich Miescher award.

The Award

Sophie Martin will receive the EMBO Gold Medal and an award of 10,000 Euros at The FEBS-EMBO Meeting in Paris where she will also give a lecture about her research.

See the EMBO Press Release for more details.