Different subsets of the tRNA pool in human are expressed in different cellular conditions. The 'proliferation-tRNAs' are induced upon normal and cancerous cell division, while the 'differentiation tRNAs' are active in non-dividing, differentiated cells. Here we examine the essentiality of the various tRNAs upon cellular growth and arrest. We established a CRISPR-based editing procedure with sgRNAs that each target a tRNA family. We measured tRNA essentiality for cellular growth and found that most proliferation tRNAs are essential compared to differentiation tRNAs in rapidly growing cell lines. Yet in more slowly dividing lines, the differentiation tRNAs were more essential. In addition, we measured the essentiality of each tRNA family upon response to cell cycle arresting signals. Here we detected a more complex behavior with both proliferation-tRNAs and differentiation-tRNAs showing various levels of essentiality. These results provide the so-far most comprehensive functional characterization of human tRNAs with intricate roles in various cellular states.
Source data files have been provided for Figure 1.Sequencing data are available in GEO under the accession code GSE163611
Manipulation of the human tRNA pool reveals distinct tRNA sets that act in cellular proliferation or cell cycle arrest.NCBI Gene Expression Omnibus, GSE163611.
- Yitzhak Pilpel
- Yitzhak Pilpel
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Ivan Topisirovic, Jewish General Hospital, Canada
© 2020, Aharon-Hefetz 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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