A serial multiplex immunogold labeling method for identifying peptidergic neurons in connectomes

Abstract

Electron microscopy-based connectomics aims to comprehensively map synaptic connections in neural tissue. However, current approaches are limited in their capacity to directly assign molecular identities to neurons. Here, we use serial multiplex immunogold labeling (siGOLD) and serial-section transmission electron microscopy (ssTEM) to identify multiple peptidergic neurons in a connectome. The high immunogenicity of neuropeptides and their broad distribution along axons, allowed us to identify distinct neurons by immunolabeling small subsets of sections within larger series. We demonstrate the scalability of siGOLD by using 11 neuropeptide antibodies on a full-body larval ssTEM dataset of the annelid Platynereis. We also reconstruct a peptidergic circuitry comprising the sensory nuchal organs, found by siGOLD to express pigment-dispersing factor, a circadian neuropeptide. Our approach enables the direct overlaying of chemical neuromodulatory maps onto synaptic connectomic maps in the study of nervous systems.

Article and author information

Author details

  1. Réza Shahidi

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Elizabeth A Williams

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Markus Conzelmann

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Albina Asadulina

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Csaba Verasztó

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Sanja Jasek

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Luis A Bezares-Calderón

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Gáspár Jékely

    Max-Planck-Institute for Developmental Biology, Tübingen, Germany
    For correspondence
    gaspar.jekely@tuebingen.mpg.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Ronald L Calabrese, Emory University, United States

Publication history

  1. Received: August 26, 2015
  2. Accepted: November 27, 2015
  3. Accepted Manuscript published: December 15, 2015 (version 1)
  4. Version of Record published: January 28, 2016 (version 2)

Copyright

© 2015, Shahidi 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. Réza Shahidi
  2. Elizabeth A Williams
  3. Markus Conzelmann
  4. Albina Asadulina
  5. Csaba Verasztó
  6. Sanja Jasek
  7. Luis A Bezares-Calderón
  8. Gáspár Jékely
(2015)
A serial multiplex immunogold labeling method for identifying peptidergic neurons in connectomes
eLife 4:e11147.
https://doi.org/10.7554/eLife.11147

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