Partitioning Variability of a Compartmentalized In Vitro Transcriptional Thresholding Circuit.

摘要: Encapsulation of in vitro biochemical reaction circuits into small, cell-sized compartments can result considerable variations the dynamical properties circuits. As a model system, we here investigate simple transcriptional circuit, which generates an ultrasensitive fluorescence response when concentration RNA transcript reaches preset threshold. The circuit is compartmentalized spherical water-in-oil microemulsion droplets, and progress monitored by microscopy. A quantitative statistical analysis thousands individual droplets ranging size from few up to 20 μm reveals strong variability effective production rates, computational modeling traced back larger-than-Poisson RNAP activities droplets. noise level terms strength (the Fano factor) strongly dependent on ratio between transcription templates polymerases, increases for hig...