How Do Cells Learn to Move in Unison?

Article Content

In the quest to understand how complex life forms, scientists have long-wondered how sheets of cells begin to move together to form organs—especially when these sheets form closed, sphere-like surfaces with no edges to direct motion. Researchers at UC San Diego and the University of Chicago used a combination of live imaging, genetic experiments and mathematical modeling to understand how cells in the fruit fly egg chamber synchronize movement with each other.

They found that cells can spontaneously organize into a coordinated global rotation through a self-reinforcing mechanism where a specific protein helps individual cells align their movement. Once the cells start moving, that motion polarizes the protein to the back of the cell, which promotes further movement from the rear cell in the same direction. The coordination of cell movements is mediated by mechanical connections between adjacent cells and the global egg chamber geometry.

The study also explains why the egg chamber always rotates around its long axis. Initially, this is caused by the physical forces through which the egg chamber interacts with nearby support tissues. As the egg chamber grows and becomes more oval-shaped, its own geometry helps stabilize the rotation axis.

This work holds potential implications for understanding both normal development and diseases in which collective cell movement goes awry.