Replicative aging of Saccharomyces cerevisiae is an established model system for eukaryotic cellular aging. A limitation in yeast lifespan studies has been the difficulty of separating old cells from young cells in large quantities. We engineered a new platform, the Miniature-chemostat Aging Device (MAD), that enables purification of aged cells at sufficient quantities for genomic and biochemical characterization of aging yeast populations. Using MAD, we measured DNA accessibility and gene expression changes in aging cells. Our data highlight an intimate connection between aging, growth rate, and stress. Stress-independent genes that change with age are highly enriched for targets of the signal recognition particle (SRP). Combining MAD with an improved ATAC-Seq method, we find that increasing proteasome activity reduces rDNA instability usually observed in aging cells, and contrary to published findings, provide evidence that global nucleosome occupancy does not change significantly with age.
We've included all processed data in easily accessible tables.Sequencing data have been deposited in GEO under accession codes GSE118581
Genomic analysis of aging yeastPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE118581).
This was work was funded by Calico Life Sciences, LLC
- Matt Kaeberlein, University of Washington, United States
© 2018, Hendrickson 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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