1. Neuroscience
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High-throughput synapse-resolving two-photon fluorescence microendoscopy for deep-brain volumetric imaging in vivo

  1. Guanghan Meng
  2. Yajie Liang
  3. Sarah Sarsfield
  4. Wan-chen Jiang
  5. Rongwen Lu
  6. Joshua Tate Dudman
  7. Yeka Aponte
  8. Na Ji  Is a corresponding author
  1. University of California, Berkeley, United States
  2. Janelia Research Campus, Howard Hughes Medical Institute, United States
  3. National Institute on Drug Abuse, United States
  4. Johns Hopkins University School of Medicine, United States
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Cite this article as: eLife 2019;8:e40805 doi: 10.7554/eLife.40805

Abstract

Optical imaging has become a powerful tool for studying brains in vivo. The opacity of adult brains makes microendoscopy, with an optical probe such as a gradient index (GRIN) lens embedded into brain tissue to provide optical relay, the method of choice for imaging neurons and neural activity in deeply buried brain structures. Incorporating a Bessel focus scanning module into two-photon fluorescence microendoscopy, we extended the excitation focus axially and improved its lateral resolution. Scanning the Bessel focus in 2D, we imaged volumes of neurons at high-throughput while resolving fine structures such as synaptic terminals. We applied this approach to the volumetric anatomical imaging of dendritic spines and axonal boutons in the mouse hippocampus, and functional imaging of GABAergic neurons in the mouse lateral hypothalamus in vivo.

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Author details

  1. Guanghan Meng

    Department of Physics, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.

  2. Yajie Liang

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    No competing interests declared.

  3. Sarah Sarsfield

    Neuronal Circuits and Behavior Unit, National Institute on Drug Abuse, Baltimore, United States
    Competing interests
    No competing interests declared.

  4. Wan-chen Jiang

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    No competing interests declared.

  5. Rongwen Lu

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    Rongwen Lu, The Bessel focus scanning intellectual property has been licensed to Thorlabs, Inc. by HHMI.

  6. Joshua Tate Dudman

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4436-1057

  7. Yeka Aponte

    Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5967-2579

  8. Na Ji

    Department of Physics, University of California, Berkeley, Berkeley, United States
    For correspondence
    jina@berkeley.edu
    Competing interests
    Na Ji, The Bessel focus scanning intellectual property has been licensed to Thorlabs, Inc. by HHMI.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5527-1663

Funding

Howard Hughes Medical Institute

  • Guanghan Meng
  • Yajie Liang
  • Wan-chen Jiang
  • Rongwen Lu
  • Joshua Tate Dudman
  • Na Ji

National Institute of Neurological Disorders and Stroke

  • Guanghan Meng
  • Na Ji

National Institute on Drug Abuse

  • Sarah Sarsfield
  • Yeka Aponte

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

Ethics

Animal experimentation: All animal experiments were conducted according to the United States National Institutes of Health guidelines for animal research. Procedures and protocols were approved by the Institutional Animal Care and Use Committee at Janelia Research Campus, Howard Hughes Medical Institute (protocol number: 16-147)

Reviewing Editor

  1. David Kleinfeld, University of California, San Diego, United States

Publication history

  1. Received: August 5, 2018
  2. Accepted: December 20, 2018
  3. Accepted Manuscript published: January 3, 2019 (version 1)
  4. Accepted Manuscript updated: January 4, 2019 (version 2)
  5. Version of Record published: January 18, 2019 (version 3)

Copyright

© 2019, Meng 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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