Mechanical Properties of Transcription

TL;DR

This paper presents a physical model of transcription mechanics, linking RNA elongation, polymerase rotation, and DNA supercoiling, with implications for gene regulation and genome structure.

Contribution

It introduces a coupled physical framework of transcription mechanics, enabling experimental extraction of mechanical parameters and understanding transcriptional stalling.

Findings

Derived asymptotic behavior for transcription dynamics

Provided equations describing RNA polymerase rotation and DNA supercoiling

Discussed implications for gene expression and chromatin structure

Abstract

Recently the physical characterization of a number of biological processes has proven indispensable for a full understanding of natural phenomena. One such example is the mechanical properties of transcription, which have been shown to have significant effects in gene expression. In this letter we introduce a simple description of the basic physical elements of transcription where RNA elongation, RNA polymerase rotation and DNA supercoiling are coupled. The resulting framework describes the relative amount of RNA polymerase rotation and DNA supercoiling that occurs during RNA elongation. Asymptotic behavior is derived and can be used to experimentally extract unknown mechanical parameters of transcription. Incorporation of mechanical limits to RNA polymerase is accomplished yielding an equation of motion for DNA supercoiling and RNA elongation with transcriptional stalling. Important implications for gene expression, chromatin structure and genome organization are discussed.