1. Biochemistry and Chemical Biology
  2. Cell Biology

Gene activation by a CRISPR-assisted trans enhancer

  1. Xinhui Xu
  2. Jinliang Gao
  3. Wei Dai
  4. Danyang Wang
  5. Jian Wu
  6. Jinke Wang  Is a corresponding author
  1. Southeast University, China
https://doi.org/10.7554/eLife.45973
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  1. Xinhui Xu
  2. Jinliang Gao
  3. Wei Dai
  4. Danyang Wang
  5. Jian Wu
  6. Jinke Wang
(2019)
Gene activation by a CRISPR-assisted trans enhancer
eLife 8:e45973.
https://doi.org/10.7554/eLife.45973
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Abstract

The deactivated CRISPR/Cas9 (dCas9) is now the most widely-used gene activators. However, the current dCas9-based gene activators are still limited by their unsatisfactory activity. In this study, we developed a new strategy, CRISPR-assisted trans enhancer, for activating gene expression in high efficiency by combining dCas9-VP64/sgRNA with the widely used strong CMV enhancer. In this strategy, a CMV enhancer DNA was recruited to target gene in trans by two systems, dCas9-VP64/csgRNA-sCMV and dCas9-VP64-GLA4/sgRNA-UAS-CMV. The former recruited trans enhancer by the annealing between two short complementary oligonucleotides at the ends of sgRNA and trans enhancer. The latter recruited trans enhancer by the binding between GLA4 fused to dCas9 and UAS sequence of trans enhancer. The trans enhancer activated gene transcription as the natural looped cis enhancer. The trans enhancer could activate both exogenous reporter gene and variant endogenous genes in various cells, with much higher activation efficiency than the current dCas9 activators.

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All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Xinhui Xu

    State Key Laboratory of Bioelectronics, Southeast University, Nanjing, China
    Competing interests
    The authors declare that no competing interests exist.

  2. Jinliang Gao

    State Key Laboratory of Bioelectronics, Southeast University, Nanjing, China
    Competing interests
    The authors declare that no competing interests exist.

  3. Wei Dai

    State Key Laboratory of Bioelectronics, Southeast University, Nanjing, China
    Competing interests
    The authors declare that no competing interests exist.

  4. Danyang Wang

    State Key Laboratory of Bioelectronics, Southeast University, Nanjing, China
    Competing interests
    The authors declare that no competing interests exist.

  5. Jian Wu

    State Key Laboratory of Bioelectronics, Southeast University, Nanjing, China
    Competing interests
    The authors declare that no competing interests exist.

  6. Jinke Wang

    State Key Laboratory of Bioelectronics, Southeast University, Nanjing, China
    For correspondence
    wangjinke@seu.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3352-4690

Funding

National Natural Science Foundation of China (61571119)

  • Jinke Wang

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2019, Xu 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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  1. Xinhui Xu
  2. Jinliang Gao
  3. Wei Dai
  4. Danyang Wang
  5. Jian Wu
  6. Jinke Wang
(2019)
Gene activation by a CRISPR-assisted trans enhancer
eLife 8:e45973.
https://doi.org/10.7554/eLife.45973

Share this article

https://doi.org/10.7554/eLife.45973

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