Publication in J Cell Sci for Agathe Chaigne and colleagues

How do cells control spindle positioning in three-dimensional environments? A new publication in Journal of Cell Science by Agathe Chaigne and colleagues reveals three-dimensional geometry controls division symmetry in stem cell colonies. The study uses mouse embryonic stem cells as a model system and finds that they can divide asymmetrically in size (one cell bigger than the other). This assymetry is controlled by the geometry of the colony, as cells at the border of a ball of cells divide assymetrically this more often than cells inside the ball. The mechanism appears to be controlled by E-Cadherin, a component of cell-cell junctions. Interestingly, when the cells change fate towards differentiation, they divide more symmetrically, suggesting that controlling division size fidelity is more important in differentiated cells than stem cells.