Characterization of dependencies between growth and division in budding yeast
Abstract
Cell growth and division are processes vital to the proliferation and development of life. Coordination between these two processes has been recognized for decades in a variety of organisms. In the budding yeastSaccharomyces cerevisiae, this coordination or ‘size control’ appears as an inverse correlation between cell size and the rate of cell-cycle progression, routinely observed in G1prior to cell division commitment. Beyond this point, cells are presumed to complete S/G2/M at similar rates and in a size-independent manner. As such, studies of dependence between growth and division have focused on G1. Moreover, in unicellular organisms, coordination between growth and division has commonly been analysedwithinthe cycle of a single cell without accounting for correlations in growth and division characteristicsbetweencycles of related cells. In a comprehensive analysis of three published time-lapse microscopy datasets, we analyse both intra- and inter-cycle dependencies between growth and division, revisiting assumptions about the coordination between these two processes. Interestingly, we find evidence (i) that S/G2/M durations are systematically longer in daughters than in mothers, (ii) of dependencies between S/G2/M and size at budding that echo the classical G1dependencies, and (iii) in contrast with recent bacterial studies, of negative dependencies between size at birth and size accumulated during the cell cycle. In addition, we develop a novel hierarchical model to uncover inter-cycle dependencies, and we find evidence for such dependencies in cells growing in sugar-poor environments. Our analysis highlights the need for experimentalists and modellers to account for new sources of cell-to-cell variation in growth and division, and our model provides a formal statistical framework for the continued study of dependencies between biological processes.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 01, 2017
- Source ID
- 10.1098/rsif.2016.0993
Entities
People
- Alexander J. Hartemink
- Edwin S. Iversen
- Michael B Mayhew
Organizations
- Defense Advanced Research Projects Agency
- Duke University
- Lawrence Livermore National Laboratory
- National Institutes of Health