Mechanical Bounds to Transcriptional Noise

TL;DR

This paper introduces a simple phenomenological model that links mechanical feedback to transcriptional bursting, explaining how mechanical limits influence the intrinsic noise in gene expression.

Contribution

It presents a novel model integrating mechanical feedback with traditional gene expression theories to explain universal noise properties.

Findings

Intrinsic noise lower limit increases with mean expression level.

Mechanical feedback can account for transcriptional bursting phenomena.

Universal properties of gene expression emerge from mechanical constraints.

Abstract

Over the last several decades it has been increasingly recognized that stochastic processes play a central role in transcription. Though many stochastic effects have been explained, the source of transcriptional bursting (one of the most well-known sources of stochasticity) has continued to evade understanding. Recent results have pointed to mechanical feedback as the source of transcriptional bursting but a reconciliation of this perspective with preexisting views of transcriptional regulation is lacking. In this letter we present a simple phenomenological model which is able to incorporate the traditional view of gene expression within a framework with mechanical limits to transcription. Our model explains the emergence of universal properties of gene expression, wherein the lower limit of intrinsic noise necessarily rises with mean expression level.