What lava lamps and vinaigrette can teach us about cell biology
When David Courson and Lindsay Moore arrived for a summer research placement in Woods Hole, Massachusetts, they expected to try some new techniques and play with high-end microscopes. As graduate students, they never imagined that they would help to solve a biological problem that had baffled researchers for more than 25 years.
Their instructors at the Marine Biological Laboratory asked them to decipher how pellets of RNA and protein called P granules form in worm embryos — a tall order given how long the structures had flummoxed biologists. Yet as soon as Courson and Moore started making movies of the process, they and their instructors could see something unusual happening under the microscope: the P granules were colliding and coalescing like blobs in a lava lamp.
Solid structures don’t do that; only liquids can. The P granules, they realized, were not hard kernels, as most researchers thought. Rather, they behaved like oil droplets in a bottle of vigorously shaken vinaigrette, first dispersing, then quickly fusing and blending into larger liquid blobs.