Gene expression stochastic results

A similar approach was used to discriminate between intrinsic noise, stochastic fluctuations that arise from fluctuations of the molecules directly involved in gene expression, and extrinsic contributions that arise form fluctuations in other molecules that regulate or otherwise contribute to the process [22]. The latter are uniform within a cell but vary from cell to cell while the former produce fluctuations over time within an individual cell. The two forms of noise were distinguished by determining the extent of correlation between the expression of cyan and yellow fluorescent proteins under the control of identical promoters in the same cell. The intrinsic noise was measured as the difference in fluorescence intensity of the YFP and CFP. The extrinsic noise was determined by using the fact that the square of the total noise equals the sum of the squares of the intrinsic and extrinsic noises. The results show that both types of noise contribute significantly. 

The results coming from our stochastic modeling are geared to aid experimental design, and experimental validation of our predictions will be needed to further explore and improve our understanding of the compartmentalized PS. A better description of liposome formation kinetics will also help the community to test different encapsulation efficiencies for different molecules, which will in turn affect the internal gene expression kinetics. 

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