Semi-Markov models of mRNA-translation

TL;DR

This paper models mRNA translation using semi-Markov processes to account for non-exponential waiting times, providing insights into protein production distributions and an analytically solvable model.

Contribution

It introduces a semi-Markov model for translation that incorporates experimentally observed non-exponential waiting times, advancing beyond traditional exponential assumptions.

Findings

Distribution P(E) is non-geometric for small E

Numerical simulations with realistic parameters conducted

Analytically solvable semi-Markov model relates P(E) to production times

Abstract

Translation is the cellular process in which ribosomes make proteins from information encoded on messenger RNA (mRNA). We model translation with an exclusion process taking into account the experimentally determined, non-exponential, waiting time between steps of a ribosome. From numerical simulations using realistic parameter values, we determine the distribution P(E) of the number of proteins E produced by one mRNA. We find that for small E this distribution is not geometric. We present a simplified and analytically solvable semi-Markov model that relates P(E) to the distributions of the times to produce the first E proteins.