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Anomalous Scaling of Gene Expression in Confined Cell-Free Reactions.

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 size-dependence of R³. Given that TXTL becomes less efficient at thin surface layer, a mathematical model explains the anomalous size-dependence found in experiment. The surface of cell-sized compartment can thus play a regulatory role for cell-free gene expression.

SUBMITTER: Sakamoto R

PROVIDER: S-EPMC5943292 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Anomalous Scaling of Gene Expression in Confined Cell-Free Reactions.

Sakamoto Ryota R Noireaux Vincent V Maeda Yusuke T YT

Scientific reports 20180509 1

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 R<sup>4</sup> different from the expected size-dependence of R<sup>3</sup>. Given that TXTL becomes less efficient a ...[more]

PMID: 29743508

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