Distinguishing different modes of growth using single-cell data
- Harvard University, United States
- University of Tennessee, United States
- The University of Tennessee, United States
Abstract
Collection of high-throughput data has become prevalent in biology. Large datasets allow the use of statistical constructs such as binning and linear regression to quantify relationships between variables and hypothesize underlying biological mechanisms based on it. We discuss several such examples in relation to single-cell data and cellular growth. In particular, we show instances where what appears to be ordinary use of these statistical methods leads to incorrect conclusions such as growth being non-exponential as opposed to exponential and vice versa. We propose that the data analysis and its interpretation should be done in the context of a generative model, if possible. In this way, the statistical methods can be validated either analytically or against synthetic data generated via the use of the model, leading to a consistent method for inferring biological mechanisms from data. On applying the validated methods of data analysis to infer cellular growth on our experimental data, we find the growth of length in E. coli to be non-exponential. Our analysis shows that in the later stages of the cell cycle the growth rate is faster than exponential.
Data availability
All data generated during this study are deposited in Dataverse-:Kar, Prathitha; Tiruvadi-Krishnan, Sriram; Männik, Jaana; Männik, Jaan; Amir, Ariel, 2021, "Distinguishing different modes of growth using single-cell data", https://doi.org/10.7910/DVN/BNQUDW, Harvard Dataverse, V1
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Data from long-term growth data of Escherichia coli at a single-cell levelFigshare, doi: 10.6084/m9.figshare.c.3493548.
Article and author information
Author details
Funding
US-Israel BSF Research Grant (2017004)
- Jaan Männik
National Institutes of Health (R01GM127413)
- Jaan Männik
National Science Foundation (NSF CAREER 1752024)
- Ariel Amir
National Science Foundation (NSF award 1806818)
- Prathitha Kar
National Institutes of Health (NIH grant 103346)
- Prathitha Kar
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Kar 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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Distinguishing different modes of growth using single-cell data
eLife 10:e72565.
https://doi.org/10.7554/eLife.72565
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