Synaptic and peptidergic connectome of a neurosecretory centre in the annelid brain
Neurosecretory centers in animal brains use peptidergic signaling to influence physiology and behavior. Understanding neurosecretory center function requires mapping cell types, synapses, and peptidergic networks. Here we use transmission electron microscopy and gene expression mapping to analyze the synaptic and peptidergic connectome of an entire neurosecretory center. We reconstructed 78 neurosecretory neurons and mapped their synaptic connectivity in the brain of larval Platynereis dumerilii, a marine annelid. These neurons form an anterior neurosecretory center expressing many neuropeptides, including hypothalamic peptide orthologs and their receptors. Analysis of peptide-receptor pairs in spatially mapped single-cell transcriptome data revealed sparsely connected networks linking specific neuronal subsets. We experimentally analyzed one peptide-receptor pair and found that a neuropeptide can couple neurosecretory and synaptic brain signaling. Our study uncovered extensive networks of peptidergic signaling within a neurosecretory center and its connection to the synaptic brain.
Article and author information
- Elizabeth A Williams
- Csaba Verasztó
- Sanja Jasek
- Markus Conzelmann
- Philipp Bauknecht
Deutsche Forschungsgemeinschaft (JE 777/1-1)
- Elizabeth A Williams
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Oliver Hobert, Howard Hughes Medical Institute, Columbia University, United States
- Received: February 24, 2017
- Accepted: December 2, 2017
- Accepted Manuscript published: December 4, 2017 (version 1)
- Accepted Manuscript updated: December 13, 2017 (version 2)
- Version of Record published: December 29, 2017 (version 3)
© 2017, Williams 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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