Synthetic mammalian transgene negative autoregulation

Molecular Systems Biology

Vinay Shimoga¹  Jacob T White¹  Yi Li¹  Eduardo Sontag² 

[1] Bioengineering Department, The University of Texas at Dallas, Richardson, TX, USA;Department of Mathematics, Rutgers University, New Brunswick, NJ, USA

关键词: cellular noise;    human cells;    negative feedback;    transgenes;   

DOI  :  10.1038/msb.2013.27

来源: Wiley

【 摘 要 】

Abstract

Biological networks contain overrepresented small-scale topologies, typically called motifs. A frequently appearing motif is the transcriptional negative-feedback loop, where a gene product represses its own transcription. Here, using synthetic circuits stably integrated in human kidney cells, we study the effect of negative-feedback regulation on cell-wide (extrinsic) and gene-specific (intrinsic) sources of uncertainty. We develop a theoretical approach to extract the two noise components from experiments and show that negative feedback results in significant total noise reduction by reducing extrinsic noise while marginally increasing intrinsic noise. We compare the results to simple negative regulation, where a constitutively transcribed transcription factor represses a reporter protein. We observe that the control architecture also reduces the extrinsic noise but results in substantially higher intrinsic fluctuations. We conclude that negative feedback is the most efficient way to mitigate the effects of extrinsic fluctuations by a sole regulatory wiring.

Synopsis

The effect of negative feedback on global and local sources of uncertainty is studied with synthetic circuits stably integrated in human cells. Negative feedback is shown to be the most efficient way to mitigate the effects of global fluctuations by introducing a single additional regulatory link.

• A method is presented to extract the extrinsic and intrinsic noise contributions from measurements of two reporter proteins controlled by non-identical promoters.
• Negative feedback reduces total noise in human transgene integrations.
• Negative feedback reduces extrinsic noise while it marginally increases intrinsic noise.
• Negative feedback is the most efficient way to mitigate the effects of extrinsic fluctuations by a single regulatory link.

【 授权许可】

CC BY-NC-SA   
Copyright © 2013 EMBO and Macmillan Publishers Limited

Creative Commons Attribution License, which permits distribution, and reproduction in any medium, provided the original author and source are credited. This license does not permit commercial exploitation without specific permission.