1. Neuroscience
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Cre-assisted fine-mapping of neural circuits using orthogonal split inteins

  1. Haojiang Luan
  2. Alexander Kuzin
  3. Ward F Odenwald
  4. Benjamin H White  Is a corresponding author
  1. National Institute of Mental Health, United States
  2. National Institute of Neurological Disease and Stroke, United States
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Cite this article as: eLife 2020;9:e53041 doi: 10.7554/eLife.53041

Abstract

Existing genetic methods of neuronal targeting do not routinely achieve the resolution required for mapping brain circuits. New approaches are thus necessary. Here, we introduce a method for refined neuronal targeting that can be applied iteratively. Restriction achieved at the first step can be further refined in a second step, if necessary. The method relies on first isolating neurons within a targeted group (i.e. Gal4 pattern) according to their developmental lineages, and then intersectionally limiting the number of lineages by selecting only those in which two distinct neuroblast enhancers are active. The neuroblast enhancers drive expression of split Cre recombinase fragments. These are fused to non-interacting pairs of split inteins, which ensure reconstitution of active Cre when all fragments are expressed in the same neuroblast. Active Cre renders all neuroblast-derived cells in a lineage permissive for Gal4 activity. We demonstrate how this system can facilitate neural circuit-mapping in Drosophila.

Data availability

Data generated during this study are included in the manuscript and supporting files. Source data files have been provided for Figure 2I

Article and author information

Author details

  1. Haojiang Luan

    Laboratory of Molecular Biology, National Institute of Mental Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Alexander Kuzin

    Neural Cell-Fate Determinants Section, National Institute of Neurological Disease and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Ward F Odenwald

    Neural Cell-Fate Determinants Section, National Institute of Neurological Disease and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Benjamin H White

    Laboratory of Molecular Biology, National Institute of Mental Health, Bethesda, United States
    For correspondence
    benjaminwhite@mail.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0612-8075

Funding

National Institute of Mental Health (ZIA-MH002800)

  • Benjamin H White

National Institute of Neurological Disorders and Stroke (ZIA-NS002820-26)

  • Ward F Odenwald

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

Reviewing Editor

  1. K VijayRaghavan, National Centre for Biological Sciences, Tata Institute of Fundamental Research, India

Publication history

  1. Received: October 24, 2019
  2. Accepted: April 11, 2020
  3. Accepted Manuscript published: April 14, 2020 (version 1)
  4. Version of Record published: May 12, 2020 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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