Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2017 Jun 27;45(14):8190–8198. doi: 10.1093/nar/gkx556

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com

PMC Copyright notice

Figure 1. — The S-phase duration is the maximum between the stochastic termination time of all inter-origin regions. The illustration considers replication of one linear chromosome with three origins. (A) The activation of each origin is stochastic, and the firing time follows a given phenomenological distribution. (B) In each cell, each origin randomly chooses a firing time from this distribution. The last replicated inter-origin region, which may be different in different cells, determines the total duration of the S phase. In the sketch, red circles indicate origins. Dark blue circles indicate the latest replicated loci for each inter-origin region. Some origins (e.g. the one between I₂ and I₃ in cell 1) may be replicated passively, and never fire in some realization. (C) The stochastic model generates a distribution of S-phase durations, which expresses the cell-to-cell variability. The parameters used in the plots are: chromosome length L = 300 kb, fork velocity = 1 kb/min, firing exponent γ = 0 (blue line in (A) and blue circles in (C)) or 1 (red line in (A) and red triangles in (C)), origin locations x₁ = 50 kb, x₂ = 150 kb and x₃ = 250 kb, origin strength λ_{1, 2, 3} = 0.02 min ⁻¹ (for γ = 0) or 6.3 × 10⁻⁴ min ⁻² (for γ = 1).

Inline graphic — The S-phase duration is the maximum between the stochastic termination time of all inter-origin regions. The illustration considers replication of one linear chromosome with three origins. (A) The activation of each origin is stochastic, and the firing time follows a given phenomenological distribution. (B) In each cell, each origin randomly chooses a firing time from this distribution. The last replicated inter-origin region, which may be different in different cells, determines the total duration of the S phase. In the sketch, red circles indicate origins. Dark blue circles indicate the latest replicated loci for each inter-origin region. Some origins (e.g. the one between I₂ and I₃ in cell 1) may be replicated passively, and never fire in some realization. (C) The stochastic model generates a distribution of S-phase durations, which expresses the cell-to-cell variability. The parameters used in the plots are: chromosome length L = 300 kb, fork velocity = 1 kb/min, firing exponent γ = 0 (blue line in (A) and blue circles in (C)) or 1 (red line in (A) and red triangles in (C)), origin locations x₁ = 50 kb, x₂ = 150 kb and x₃ = 250 kb, origin strength λ_{1, 2, 3} = 0.02 min ⁻¹ (for γ = 0) or 6.3 × 10⁻⁴ min ⁻² (for γ = 1).