video: Top left: Fluorescence images from a time lapse experiment show how a periodically modulated concentration of the transcriptional inducer arabinose (red) entrains a synthetic genetic oscillator that drives the expression of the green fluorescent protein (green) in single bacterial cells. Top right: In contrast, like circadian clocks in constant darkness, synthetic oscillators run sustainedly but mutually out of phase in a constant concentration of inducers. Bottom left and right: Inducer concentration and multiple single-cell fluorescence traces as a function of time from the respective experiments shown above. Left: Oscillations in entrained single cells track the sinusoidal environmental input (period of 30 min.) with a definite phase lag. Right: Synthetic oscillations are asynchronous in a constant environment. This video relates to an article that appeared in the Sept. 2, 2011, issue of Science, published by AAAS. The study, by Dr. O. Mondragón-Palomino of the University of California, San Diego in La Jolla, Calif., and colleagues was titled, "Entrainment of a Population of Synthetic Genetic Oscillators.” view more
Credit: Video © <i>Science</i>/AAAS