Whole-brain connectivity atlas of glutamatergic and GABAergic neurons in the mouse dorsal and median raphe nuclei
- Huazhong University of Science and Technology (HUST), China
- HUST-Suzhou Institute for Brainsmatics, China
- Hainan University, China
Abstract
The dorsal raphe nucleus (DR) and median raphe nucleus (MR) contain populations of glutamatergic and GABAergic neurons that regulate diverse behavioral functions. However, their whole-brain input-output circuits remain incompletely elucidated. We used viral tracing combined with fluorescence micro-optical sectioning tomography to generate a comprehensive whole-brain atlas of inputs and outputs of glutamatergic and GABAergic neurons in the DR and MR. We found that these neurons received inputs from similar upstream brain regions. The glutamatergic and GABAergic neurons in the same raphe nucleus had divergent projection patterns with differences in critical brain regions. Specifically, MR glutamatergic neurons projected to the lateral habenula through multiple pathways. Correlation and cluster analysis revealed that glutamatergic and GABAergic neurons in the same raphe nucleus received heterogeneous inputs and sent different collateral projections. This connectivity atlas further elucidates the anatomical architecture of the raphe nuclei, which could facilitate better understanding of their behavioral functions.
Data availability
The analysis results and data have been uploaded in the form of Supplementary Table.To present and share the TB-sized raw data, we developed an interactive website (http://atlas.brainsmatics.org/a/xu2011).
Article and author information
Author details
Funding
National Natural Science Foundation of China (91749209)
- Qingming Luo
National Natural Science Foundation of China (61890953)
- Hui Gong
National Natural Science Foundation of China (91827901)
- Anan Li
Science Fund for Creative Research Groups (61721092)
- Qingming Luo
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 approved by the Institutional Animal Care and Use Committee at HUST-Suzhou Institute For Brainsmatics (S20190601) and were conducted in accordance with relevant guidelines.
Copyright
© 2021, Xu 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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Whole-brain connectivity atlas of glutamatergic and GABAergic neurons in the mouse dorsal and median raphe nuclei
eLife 10:e65502.
https://doi.org/10.7554/eLife.65502
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