The subiculum is a patchwork of discrete subregions
- Janelia Research Campus, Howard Hughes Medical Institute, United States
Abstract
In the hippocampus, the classical pyramidal cell type of the subiculum acts as a primary output, conveying hippocampal signals to a diverse suite of downstream regions. Accumulating evidence suggests that the subiculum pyramidal cell population may actually be comprised of discrete subclasses. Here, we investigated the extent and organizational principles governing pyramidal cell heterogeneity throughout the mouse subiculum. Using single-cell RNA-seq, we find that the subiculum pyramidal cell population can be deconstructed into eight separable subclasses. These subclasses were mapped onto abutting spatial domains, ultimately producing a complex laminar and columnar organization with heterogeneity across classical dorsal-ventral, proximal-distal, and superficial-deep axes. We further show that these transcriptomically defined subclasses correspond to differential protein products and can be associated with specific projection targets. This work deconstructs the complex landscape of subiculum pyramidal cells into spatially segregated subclasses that may be observed, controlled, and interpreted in future experiments.
Data availability
Raw and processed scRNA-seq datasets have been deposited in the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus under GEO: GSE113069.
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The subiculum is a patchwork of discrete subregionsNCBI Gene Expression Omnibus, GSE113069.
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Dissociable structural and functional hippocampal outputs via distinct subiculum cell classesNCBI Gene Expression Omnibus, GSE100449.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Mark S Cembrowski
- Lihua Wang
- Andrew L Lemire
- Monique Copeland
- Salvatore F DiLisio
- Jody Clements
- Nelson Spruston
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Experimental procedures were approved by the Institutional Animal Care and Use Committee at the Janelia Research Campus.(protocols 14-118 and 17-159).
Copyright
© 2018, Cembrowski 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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The subiculum is a patchwork of discrete subregions
eLife 7:e37701.
https://doi.org/10.7554/eLife.37701
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