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A web tool for the design of prime-editing guide RNAs
- Ryan D. Chow ORCID:orcid.org/0000-0002-1872-63071,2,3,4 na1,
- Jennifer S. Chen ORCID:orcid.org/0000-0002-7808-26704,5,6,7 na1,
- Johanna Shen1,2,3 &
- …
- Sidi Chen ORCID:orcid.org/0000-0002-3819-50051,2,3,4,7,8,9,10,11,12,13,14
Nature Biomedical Engineeringvolume 5, pages190–194 (2021)Cite this article
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Abstract
Prime editing enables diverse genomic alterations to be written into target sites without requiring double-strand breaks or donor templates. The design of prime-editing guide RNAs (pegRNAs), which must be customized for each edit, can however be complex and time consuming. Compared with single guide RNAs (sgRNAs), pegRNAs have an additional 3′ extension composed of a primer binding site and a reverse-transcription template. Here we report a web tool, which we named pegFinder (http://pegfinder.sidichenlab.org), for the rapid design of pegRNAs from reference and edited DNA sequences. pegFinder can incorporate sgRNA on-target and off-target scoring predictions into its ranking system, and nominates secondary nicking sgRNAs for increasing editing efficiency. CRISPR-associated protein 9 variants with expanded targeting ranges are also supported. To facilitate downstream experimentation, pegFinder produces a comprehensive table of candidate pegRNAs, along with oligonucleotide sequences for cloning.
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Data availability
The main data supporting the results in this study are available within the paper and itsSupplementary Information. For the pegRNAs that were experimentally tested in this study, all relevant information is provided as Supplementary Information. This information can be used to recreate the pegRNA designs described here, via the pegFinder web portal (http://pegfinder.sidichenlab.org).
Code availability
The custom code is available at GitHub (https://github.com/rdchow/pegfinder). The web portal is accessible athttp://pegfinder.sidichenlab.org.
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Acknowledgements
We thank S. Eisenbarth for support. R.D.C. is supported by the Yale NIH Medical Scientist Training Program (MSTP) training grant (no. T32GM136651) and an NIH National Research Service Award (NRSA) fellowship from NCI (no. F30CA250249). J.S.C. is supported by the Yale MSTP training grant from NIH (no. T32GM136651) and an NIH NSRA fellowship from NHLBI (no. F30HL149151). S.C. is supported by Yale SBI/Genetics Startup Fund, NIH/NCI/NIDA (nos. DP2CA238295, 1R01CA231112, U54CA209992-8697, R33CA225498, RF1DA048811), DoD (no. W81XWH-20-1-0072/BC190094), AACR (nos. 499395, 17-20-01-CHEN), Cancer Research Institute (CLIP), V Foundation, Ludwig Family Foundation, Sontag Foundation (DSA), Blavatnik Family Foundation and Chenevert Family Foundation.
Author information
These authors contributed equally: Ryan D. Chow, Jennifer S. Chen.
Authors and Affiliations
Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
Ryan D. Chow, Johanna Shen & Sidi Chen
Systems Biology Institute, Yale University, West Haven, CT, USA
Ryan D. Chow, Johanna Shen & Sidi Chen
Center for Cancer Systems Biology, Yale University, West Haven, CT, USA
Ryan D. Chow, Johanna Shen & Sidi Chen
M.D.-Ph.D. Program, Yale University, New Haven, CT, USA
Ryan D. Chow, Jennifer S. Chen & Sidi Chen
Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT, USA
Jennifer S. Chen
Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
Jennifer S. Chen
Immunobiology Program, Yale University, New Haven, CT, USA
Jennifer S. Chen & Sidi Chen
Combined Program in the Biological and Biomedical Sciences, Yale University, New Haven, CT, USA
Sidi Chen
Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA
Sidi Chen
Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
Sidi Chen
Yale Stem Cell Center, Yale University School of Medicine, New Haven, CT, USA
Sidi Chen
Yale Liver Center, Yale University School of Medicine, New Haven, CT, USA
Sidi Chen
Yale Center for Biomedical Data Science, Yale University School of Medicine, New Haven, CT, USA
Sidi Chen
Center for RNA Science and Medicine, Yale University School of Medicine, New Haven, CT, USA
Sidi Chen
- Ryan D. Chow
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- Jennifer S. Chen
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- Johanna Shen
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- Sidi Chen
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Contributions
R.D.C. conceived the pegRNA design tool and developed the pegFinder algorithm. J.S.C. developed the web interface. R.D.C. and J.S. performed experiments. R.D.C. and J.S.C. wrote the manuscript. S.C. provided conceptual advice and supervised the work.
Corresponding author
Correspondence toSidi Chen.
Ethics declarations
Competing interests
The authors declare no competing interests. For full disclosure, S.C. is a co-founder, funding recipient and scientific advisor of EvolveImmune Therapeutics; the company has no relation to this study.
Additional information
Peer review information Peer reviewer reports are available.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Supplementary Information
Supplementary figures and notes.
Supplementary Dataset 1
DNA sequences used as inputs to pegFinder.
Supplementary Dataset 2
Example results produced by pegFinder, detailing candidate pegRNAs and cloning oligos for generating mutant KRAS G12D in human cells.
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Chow, R.D., Chen, J.S., Shen, J.et al. A web tool for the design of prime-editing guide RNAs.Nat Biomed Eng5, 190–194 (2021). https://doi.org/10.1038/s41551-020-00622-8
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