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bioRxiv · 10.1101/301671

Concurrent processes set E. coli cell division

Micali, G.·Grilli, J.·Osella, M.·Cosentino Lagomarsino, M.
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Abstract

A cell can divide only upon completion of chromosome segregation, or its daughters would lose genetic material [1, 2]. In E. coli bacteria, the prevalent view is that cells divide a fixed amount of time after they start to copy the chromosomes [3, 4], and a known pathway prevents cells from dividing if the chromosomes interfere with the cytokinesis machinery [5]. However, whether completion of segregation is typically the bottleneck process for the decision to divide has never been stringently tested on single cells. We show how key trends in single-cell data lead to challenge the classic idea of replication-segregation limiting cell division. Instead, the data agree with a model where two concurrent processes (setting replication initiation and inter-division time) set cell division on competing time scales. During each cell cycle, division is set by the slowest process (an \" ...

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Micali, G., Grilli, J., Osella, M., Cosentino Lagomarsino, M.. 2018-04-16. Concurrent processes set E. coli cell division. https://doi.org/10.1101/301671

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