Turning on genes may work like forming a flash mob.
Inside a cell’s nucleus, fast-moving groups of floppy proteins crowd together around gene control switches and coalesce into droplets to turn on genes, Ibrahim Cissé of MIT and colleagues report June 21 in two papers in Science.
Researchers have previously demonstrated that proteins form such droplets in the cytoplasm, the cell’s jellylike guts. Some, including Cissé’s MIT colleagues Richard Young and Phillip Sharp, have proposed that this process — called phase separation — could also happen in the nucleus when cellular machinery turns genes on, which involves copying DNA instructions into RNA messages.