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bioRxiv · 10.1101/251306

Anomalous Scaling of Gene Expression in Confined Cell-Free Reactions

Sakamoto, R.·Noireaux, V.·Maeda, Y. T.
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Abstract

Cellular surface breaks the symmetry of molecular diffusion across membrane. Here, we study how steric interactions between the surface and the bulk of cell-sized emulsion droplets alters gene expression emulated by a cell-free transcription/translation (TXTL) system. The concentration of synthesized reporter proteins in droplets of radius R shows an anomalous geometric scaling of R4 different from the expected normal size-dependence of R3. Given that TXTL becomes less efficient at thin surface layer, a mathematical model explains anomalous size-dependence found in experiment. The surface of cell-sized compartment thus plays a regulatory role for cell-free gene expression.

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Sakamoto, R., Noireaux, V., Maeda, Y. T.. 2018-01-22. Anomalous Scaling of Gene Expression in Confined Cell-Free Reactions. https://doi.org/10.1101/251306

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