Dts-seq: a simple method of library preparation for a highly reproducible characterization of the tRNA epitranscriptome by deep sequencing

High-throughput sequencing of cellular tRNAs is severely hindered by the presence of base modifications. These modifications impair the reverse transcription (RT) enzyme and prevent a large fraction of transcripts to be converted into cDNA in conventional sequence library preparation. Recent attempts to circumvent this issue made use of enzymatic treatments to remove methyl groups (Cozen et al. 2015; Zeng et al. 2015). This approach is, however, not fully satisfactory because it can clear the way to the RT enzyme for only a fraction of all tRNAs. Another approach takes advantage of the interference of modifications with RT enzymes to detect and identify them in fragmented RNA transcripts (Hauenschild et al. 2015; Helm and Motorin 2017; Schwartz and Motorin 2017). In line with this second approach, we present results of an alternate method that is simpler and fully adapted to the direct characterization and quantification of mature tRNA transcripts. An analysis of the obtained read coverages enables to generate highly reproductible patterns of termination signals that can be used to assess the modification state of all tRNAs. ENA Study accession : ERP116057 ; BioProject accession: PRJEB33277