Simultaneous quantification of mRNA and protein in single cells reveals post-transcriptional effects of genetic variation
Abstract
Trans-acting DNA variants may specifically affect mRNA or protein levels of genes located throughout the genome. However, prior work compared trans-acting loci mapped in separate studies, many of which had limited statistical power. Here, we developed a CRISPR-based system for simultaneous quantification of mRNA and protein of a given gene via dual fluorescent reporters in single, live cells of the yeast Saccharomyces cerevisiae. In large populations of recombinant cells from a cross between two genetically divergent strains, we mapped 86 trans-acting loci affecting the expression of ten genes. Less than 20% of these loci had concordant effects on mRNA and protein of the same gene. Most loci influenced protein but not mRNA of a given gene. One locus harbored a premature stop variant in the YAK1 kinase gene that had specific effects on protein or mRNA of dozens of genes. These results demonstrate complex, post-transcriptional genetic effects on gene expression.
Data availability
Raw DNA reads from bulk segregant mapping are available via the NCBI BioProject PRJNA644804.Transcriptome sequencing data is available at GEO under accession GSE155998.Source Data files are available for Figures 4, 5, and 7.
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Differential RNA abundance between S. cerevisiae yeast BY4741 strains with YAK1_WT and YAK1_Q578*NCBI Gene Expression Omnibus, GSE155998.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R35-GM124676)
- Frank Wolfgang Albert
Alfred P. Sloan Foundation (FG-2018- 10408)
- Frank Wolfgang Albert
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Brion 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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