Cited research: Cell 141, 682–691 (2010)

Why do identical cells often respond differently to the same stimulus? Researchers generally blame noise inherent in biological systems, but there may, in fact, be specific processes at play, according to Ido Golding, now at Baylor College of Medicine in Houston, Texas, and his co-workers.

They watched individual particles of a bacterial virus infect single Escherichia coli cells (pictured, left panel, green dots indicate virus particles) — in theory subjecting the cells to the same stimulus. Each virus particle, they found, makes an individual 'decision': to kill the host cell or to become dormant by integrating into the host's DNA. Those decisions are then summed to determine the cell's ultimate fate. Only a unanimous decision by all virus particles to integrate into the DNA of a particular cell keeps that cell alive (red). If even one particle 'votes' for death, the cell bursts (right panel, in green). A.K.

Credit: ELSEVIER