Recent results comparing the temporal program of genome replication of yeast species belonging to the Lachancea clade support the scenario that the evolution of replication timing program could be mainly driven by correlated acquisition and loss events of active replication origins. Using these results as a benchmark, we develop an evolutionary model defined as birth-death process for replication origins, and use it to identify the evolutionary biases that shape the replication timing profiles. Comparing different evolutionary models with data, we find that replication origin birth and death events are mainly driven by two evolutionary pressures, the first imposes that events leading to higher double-stall probability of replication forks are penalized, while the second makes less efficient origins more prone to evolutionary loss. This analysis provides an empirically grounded predictive framework for quantitative evolutionary studies of the replication timing program.
The code used to run the simulations, together with a readme file, was shared as a Mendeley data repository (https://data.mendeley.com/datasets/vg3r5355bj/2). The link is available in the methods section.
The evolution of the temporal program of genome replicationSRA - project number: SRP111158. Accessions ranging from SRR5807795 to SRR5807891.
- Marco Cosentino Lagomarsino
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Sandeep Krishna, National Centre for Biological Sciences‐Tata Institute of Fundamental Research, India
© 2021, Droghetti et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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