Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Protocol
  • Published:

Nucleotide resolution profiling of m7G tRNA modification by TRAC-Seq

Abstract

Precise identification of sites of RNA modification is key to studying the functional role of such modifications in the regulation of gene expression and for elucidating relevance to diverse physiological processes. tRNA reduction and cleavage sequencing (TRAC-Seq) is a chemically based approach for the unbiased global mapping of 7-methylguansine (m7G) modification of tRNAs at single-nucleotide resolution throughout the tRNA transcriptome. m7G TRAC-Seq involves the treatment of size-selected (<200 nt) RNAs with the demethylase AlkB to remove major tRNA modifications, followed by sodium borohydride (NaBH4) reduction of m7G sites and subsequent aniline-mediated cleavage of the RNA chain at the resulting abasic sites. The cleaved sites are subsequently ligated with adaptors for the construction of libraries for high-throughput sequencing. The m7G modification sites are identified using a bioinformatic pipeline that calculates the cleavage scores at individual sites on all tRNAs. Unlike antibody-based methods, such as methylated RNA immunoprecipitation and sequencing (meRIP-Seq) for enrichment of methylated RNA sequences, chemically based approaches, including TRAC-Seq, can provide nucleotide-level resolution of modification sites. Compared to the related method AlkAniline-Seq (alkaline hydrolysis and aniline cleavage sequencing), TRAC-Seq incorporates small RNA selection, AlkB demethylation, and sodium borohydride reduction steps to achieve specific and efficient single-nucleotide resolution profiling of m7G sites in tRNAs. The m7G TRAC-Seq protocol could be adapted to chemical cleavage–mediated detection of other RNA modifications. The protocol can be completed within ~9 d for four biological replicates of input and treated samples.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Partial m7G TRAC-Seq workflow.
Fig. 2: Flowchart summarizing the basic bioinformatic analyses.
Fig. 3: Isolation of small RNAs and total RNA from R1/E mESCs.
Fig. 4: SDS–PAGE analysis of purified recombinant AlkB WT and AlkB D135S.
Fig. 5: Cleavage of an m7G site in tRNA.
Fig. 6: Size distribution of the TRAC-Seq library.
Fig. 7: Anticipated result of TRAC-Seq.

Similar content being viewed by others

Data availability

The TRAC-Seq data were deposited into the Gene Expression Omnibus database (GEO accession no. GSE112670).

Code availability

The TRAC-seq data analysis source code is available via GitHub (https://github.com/rnabioinfor/TRAC-Seq, https://doi.org/10.5281/zenodo.2671795) and is for research purposes only.

References

  1. Lyons, S. M., Fay, M. M. & Ivanov, P. The role of RNA modifications in the regulation of tRNA cleavage. FEBS Lett. 592, 2828–2844 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  2. Sokolowski, M., Klassen, R., Bruch, A., Schaffrath, R. & Glatt, S. Cooperativity between different tRNA modifications and their modification pathways. Biochim Biophys. Acta Gene Regul. Mech. 1861, 409–418 (2018).

    Article  CAS  PubMed  Google Scholar 

  3. Kawarada, L. et al. ALKBH1 is an RNA dioxygenase responsible for cytoplasmic and mitochondrial tRNA modifications. Nucleic Acids Res. 45, 7401–7415 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Torres, A. G., Batlle, E. & Ribas de Pouplana, L. Role of tRNA modifications in human diseases. Trends Mol. Med. 20, 306–314 (2014).

    Article  CAS  PubMed  Google Scholar 

  5. Dominissini, D., Moshitch-Moshkovitz, S., Salmon-Divon, M., Amariglio, N. & Rechavi, G. Transcriptome-wide mapping of N(6)-methyladenosine by m(6)A-seq based on immunocapturing and massively parallel sequencing. Nat. Protoc. 8, 176–189 (2013).

    Article  CAS  PubMed  Google Scholar 

  6. Lin, S., Choe, J., Du, P., Triboulet, R. & Gregory, R. I. The m(6)A methyltransferase METTL3 promotes translation in human cancer cells. Mol. Cell 62, 335–345 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Choe, J. et al. mRNA circularization by METTL3-eIF3h enhances translation and promotes oncogenesis. Nature 561, 556–560 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Boccaletto, P. et al. MODOMICS: a database of RNA modification pathways. 2017 update. Nucleic Acids Res. 46, D303–D307 (2018).

    Article  CAS  PubMed  Google Scholar 

  9. Shaheen, R. et al. Mutation in WDR4 impairs tRNA m(7)G46 methylation and causes a distinct form of microcephalic primordial dwarfism. Genome Biol. 16, 210 (2015).

    Article  PubMed  PubMed Central  Google Scholar 

  10. Lin, S. et al. Mettl1/Wdr4-mediated m(7)G tRNA methylome is required for normal mRNA translation and embryonic stem cell self-renewal and differentiation. Mol. Cell 71, 244–255.e245 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Zheng, G. et al. Efficient and quantitative high-throughput tRNA sequencing. Nat. Methods 12, 835–837 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Cozen, A. E. et al. ARM-seq: AlkB-facilitated RNA methylation sequencing reveals a complex landscape of modified tRNA fragments. Nat. Methods 12, 879–884 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Zueva, V. S., Mankin, A. S., Bogdanov, A. A. & Baratova, L. A. Specific fragmentation of tRNA and rRNA at a 7-methylguanine residue in the presence of methylated carrier RNA. Eur. J. Biochem. 146, 679–687 (1985).

    Article  CAS  PubMed  Google Scholar 

  14. Wintermeyer, W. & Zachau, H. G. Tertiary structure interactions of 7-methylguanosine in yeast tRNA Phe as studied by borohydride reduction. FEBS Lett. 58, 306–309 (1975).

    Article  CAS  PubMed  Google Scholar 

  15. Kellner, S., Burhenne, J. & Helm, M. Detection of RNA modifications. RNA Biol. 7, 237–247 (2010).

    Article  CAS  PubMed  Google Scholar 

  16. Helm, M. & Motorin, Y. Detecting RNA modifications in the epitranscriptome: predict and validate. Nat. Rev. Genet. 18, 275–291 (2017).

    Article  CAS  PubMed  Google Scholar 

  17. Marchand, V. et al. AlkAniline-Seq: profiling of m(7) G and m(3) C RNA modifications at single nucleotide resolution. Angew. Chem. 57, 16785–16790 (2018).

    Article  CAS  Google Scholar 

  18. Schwartz, S. et al. Transcriptome-wide mapping reveals widespread dynamic-regulated pseudouridylation of ncRNA and mRNA. Cell 159, 148–162 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Bailey, T. L. & Elkan, C. Fitting a mixture model by expectation maximization to discover motifs in biopolymers. Proc. Int. Conf. Intell. Syst. Mol. Biol. 2, 28–36 (1994).

    CAS  PubMed  Google Scholar 

  20. Lowe, T. M. & Eddy, S. R. tRNAscan-SE: a program for improved detection of transfer RNA genes in genomic sequence. Nucleic Acids Res. 25, 955–964 (1997).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Langmead, B. Aligning short sequencing reads with Bowtie. Curr. Protoc. Bioinforma. 32, 11.7.1–14 (2010).

    Google Scholar 

  22. Langmead, B. & Salzberg, S. L. Fast gapped-read alignment with Bowtie 2. Nat. Methods 9, 357–359 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Li, H. et al. The sequence alignment/map format and SAMtools. Bioinformatics 25, 2078–2079 (2009).

    Article  PubMed  PubMed Central  Google Scholar 

  24. Quinlan, A. R. & Hall, I. M. BEDTools: a flexible suite of utilities for comparing genomic features. Bioinformatics 26, 841–842 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Langmead, B., Trapnell, C., Pop, M. & Salzberg, S. L. Ultrafast and memory-efficient alignment of short DNA sequences to the human genome. Genome Biol. 10, R25 (2009).

    Article  PubMed  PubMed Central  Google Scholar 

  26. Li, H. & Durbin, R. Fast and accurate long-read alignment with Burrows–Wheeler transform. Bioinformatics 26, 589–595 (2010).

    Article  PubMed  PubMed Central  Google Scholar 

  27. Trapnell, C., Pachter, L. & Salzberg, S. L. TopHat: discovering splice junctions with RNA-Seq. Bioinformatics 25, 1105–1111 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Dobin, A. et al. STAR: ultrafast universal RNA-seq aligner. Bioinformatics 29, 15–21 (2013).

    Article  CAS  PubMed  Google Scholar 

  29. Kim, D., Langmead, B. & Salzberg, S. L. HISAT: a fast spliced aligner with low memory requirements. Nat. Methods 12, 357–360 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Robinson, J. T. et al. Integrative genomics viewer. Nat. Biotechnol. 29, 24–26 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Quinlan, A. R. BEDTools: the Swiss-army tool for genome feature analysis. Curr. Protoc. Bioinforma. 47, 11.12.1–34 (2014).

    Article  Google Scholar 

  32. Bailey, T. L. et al. MEME SUITE: tools for motif discovery and searching. Nucleic Acids Res. 37, W202–W208 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

S.L. was supported by grants from the National Natural Science Foundation of China (81772999), the Guangzhou People’s Livelihood Science and Technology Project (201903010006), and a Young Investigator grant from the Alex’s Lemonade Stand Foundation (GR-000000296). R.I.G. was supported by grants from the US National Institute of General Medical Sciences (R01GM086386) and the National Institute of Mental Health (R21MH118594).

Author information

Authors and Affiliations

Authors

Contributions

S.L. developed the protocol. S.L. and Y.-Z.J. performed the experiments. Q.L. designed the bioinformatic pipeline and analyzed the data. S.L., Q.L., and R.I.G. wrote the manuscript.

Corresponding authors

Correspondence to Shuibin Lin or Richard I. Gregory.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Protocols thanks Frank Lyko and other anonymous reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Related link

Key reference using this protocol

Lin, S. et al. Mol. Cell 71, 244–255.e5 (2018) https://doi.org/10.1016/j.molcel.2018.06.001

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lin, S., Liu, Q., Jiang, YZ. et al. Nucleotide resolution profiling of m7G tRNA modification by TRAC-Seq. Nat Protoc 14, 3220–3242 (2019). https://doi.org/10.1038/s41596-019-0226-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41596-019-0226-7

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing