Dissecting Stochasticity in Translation: Time in Start Codon Selection as a Case-Study

With few exceptions, biological research dealing with stochasticity in molecular and cellular biology has focused on transcriptional processes (e.g., Elowitz et al. 2002; Lipniacki et al. 2006). Consequently, philosophical analyses have also centered on its role in transcription (e.g., Casali and Merlin 2020). Nonetheless, recent empirical evidence clearly shows that stochasticity is also pervasive in translation (e.g., Boersma et al. 2019). Focusing on time and a non-canonical case of translation (i.e., standard vs. alternative start codon selection), this paper aims to disentangle a way in which stochasticity can intervene in models of this intracellular process. Having provided a definition of what we mean by stochasticity, first, we introduce two models of time in order to show where and how stochasticity can make a difference in the timing of translation processes. Second, we show how this difference can be biologically relevant for cell physiology. We conclude that, from an explanatory point of view, it is thus worth dissecting stochasticity when studying translation, gene expression and, more generally, biological processes at the molecular level.