In vivo study of gene expression with an enhanced dual-color fluorescent transcriptional timer

  1. Li He  Is a corresponding author
  2. Richard Binari
  3. Jiuhong Huang
  4. Julia Falo-Sanjuan
  5. Norbert Perrimon  Is a corresponding author
  1. Harvard Medical School, United States
  2. Chongqing University of Arts and Sciences, China
  3. Tufts University, United States

Abstract

Fluorescent transcriptional reporters are widely used as signaling reporters and biomarkers to monitor pathway activities and determine cell type identities. However, a large amount of dynamic information is lost due to the long half-life of the fluorescent proteins. To better detect dynamics, fluorescent transcriptional reporters can be destabilized to shorten their half-lives. However, applications of this approach in vivo are limited due to significant reduction of signal intensities. To overcome this limitation, we enhanced translation of a destabilized fluorescent protein and demonstrate the advantages of this approach by characterizing spatio-temporal changes of transcriptional activities in Drosophila. In addition, by combining a fast-folding destabilized fluorescent protein and a slow-folding long-lived fluorescent protein, we generated a dual-color transcriptional timer that provides spatio-temporal information about signaling pathway activities. Finally, we demonstrate the use of this transcriptional timer to identify new genes with dynamic expression patterns.

Data availability

All essential data are provided in the supplementary materials. All the reagents created by this study (plasmids and transgenic flies) will be donated to public domains including Addgene and Bloomington Stock Center.

Article and author information

Author details

  1. Li He

    Department of Genetics, Harvard Medical School, Boston, United States
    For correspondence
    Li_He@hms.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2155-606X
  2. Richard Binari

    Department of Genetics, Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jiuhong Huang

    International Academy of Targeted Therapeutics and Innovation, Chongqing University of Arts and Sciences, Chongqing, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Julia Falo-Sanjuan

    School of Graduate Biomedical Sciences, Tufts University, Medford, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Norbert Perrimon

    Department of Genetics, Harvard Medical School, Boston, United States
    For correspondence
    perrimon@receptor.med.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7542-472X

Funding

National Institute of General Medical Sciences

  • Norbert Perrimon

Damon Runyon Cancer Research Foundation

  • Li He

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

Reviewing Editor

  1. Hugo J Bellen, Baylor College of Medicine, United States

Publication history

  1. Received: February 22, 2019
  2. Accepted: May 28, 2019
  3. Accepted Manuscript published: May 29, 2019 (version 1)
  4. Version of Record published: July 26, 2019 (version 2)

Copyright

© 2019, He 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. Li He
  2. Richard Binari
  3. Jiuhong Huang
  4. Julia Falo-Sanjuan
  5. Norbert Perrimon
(2019)
In vivo study of gene expression with an enhanced dual-color fluorescent transcriptional timer
eLife 8:e46181.
https://doi.org/10.7554/eLife.46181

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