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bioRxiv · 10.1101/623371

Extrinsic noise and heavy-tailed laws in gene expression

Ham, L.·Brackston, R. D.·Stumpf, M. P. H.
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Abstract

Noise in gene expression is one of the hallmarks of life at the molecular scale. Here we derive analytical solutions to a set of models describing the molecular mechanisms underlying transcription of DNA into RNA. Our Ansatz allows us to incorporate the effects of extrinsic noise - encompassing factors external to the transcription of the individual gene - and discuss the ramifications for heterogeneity in gene product abundance that has been widely observed in single cell data. Crucially, we are able to show that heavy-tailed distributions of RNA copy numbers cannot result from the intrinsic stochasticity in gene expression alone, but must instead reflect extrinsic sources of variability.

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Ham, L., Brackston, R. D., Stumpf, M. P. H.. 2019-04-30. Extrinsic noise and heavy-tailed laws in gene expression. https://doi.org/10.1101/623371

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