Researchers at the University of California, San Diego engineered these mustard plants to produce a firefly protein called luciferase. The luciferase gene is regulated by a control panel that normally governs a gene called CCA1 — which produces a protein that plays an important role in plants’ circadian clocks. By watching when the light-producing luciferase turns on and off, the researchers can monitor CCA1 activity.

Found in "Vive La Cycles" at sciencenews.org/view/generic/id/41675/title/Vive_la_cycles

Credit: Video courtesy of Steve A. Kay, courtesy of Science/AAAS