In order to operate, our cells constantly switch protein production on and off through specific gene functions.

FORBES: Magazine Article

Dr Chalfie realised that if the GFP gene could be spliced into a chromosome next to the gene for a protein of interest, it would be controlled by the same genetic switch as that protein.

ECONOMIST: The 2008 Nobel science prizes

That protein is a switch that tells a cell to self-destruct.

FORBES: Magazine Article