A comprehensive excitatory input map of the striatum reveals novel functional organization
- Oregon Health and Science University, United States
Abstract
The striatum integrates excitatory inputs from the cortex and the thalamus to control diverse functions. Although the striatum is thought to consist of sensorimotor, associative and limbic domains, their precise demarcations and whether additional functional subdivisions exist remain unclear. How striatal inputs are differentially segregated into each domain is also poorly understood. This study presents a comprehensive map of the excitatory inputs to the mouse striatum. The input patterns reveal boundaries between the known striatal domains. The most posterior striatum likely represents a novel functional subdivision, and the dorsomedial striatum integrates highly heterogeneous, multimodal inputs. The complete thalamo-cortico-striatal circuit loop is also presented, which reveals that the thalamic subregions innervated by the basal ganglia preferentially interconnect with motor-related cortical areas. Optogenetic experiments show the subregion-specific heterogeneity in the synaptic properties of striatal inputs from both the cortex and the thalamus. This projectome will guide functional studies investigating diverse striatal functions.
Data availability
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AIBS Mouse Brain Connectivity Atlaspublicaly available for download.
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Thalamus-whole brain projection datasetDownsized images are freely available for download. Full size images are available from T. Mao lab upon request.
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R01NS081071)
- Tianyi Mao
National Institute of Mental Health (DP2OD008425)
- Haining Zhong
National Science Foundation
- Barbara J Hunnicutt
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 National Institutes of Health guidelines for animal research and were approved by the Institutional Animal Care and Use Committee (IACUC protocol number: IS00003542).
Copyright
© 2016, Hunnicutt 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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A comprehensive excitatory input map of the striatum reveals novel functional organization
eLife 5:e19103.
https://doi.org/10.7554/eLife.19103
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