Transcriptomic encoding of sensorimotor transformation in the midbrain
Abstract
Sensorimotor transformation, a process that converts sensory stimuli into motor actions, is critical for the brain to initiate behaviors. Although the circuitry involved in sensorimotor transformation has been well delineated, the molecular logic behind this process remains poorly understood. Here, we performed high-throughput and circuit-specific single-cell transcriptomic analyses of neurons in the superior colliculus (SC), a midbrain structure implicated in early sensorimotor transformation. We found that SC neurons in distinct laminae express discrete marker genes. Of particular interest, Cbln2 and Pitx2 are key markers that define glutamatergic projection neurons in the optic nerve (Op) and intermediate gray (InG) layers, respectively. The Cbln2+ neurons responded to visual stimuli mimicking cruising predators, while the Pitx2+ neurons encoded prey-derived vibrissal tactile cues. By forming distinct input and output connections with other brain areas, these neuronal subtypes independently mediate behaviors of predator avoidance and prey capture. Our results reveal that, in the midbrain, sensorimotor transformation for different behaviors may be performed by separate circuit modules that are molecularly defined by distinct transcriptomic codes.
Data availability
The scRNA-seq data used in this study have been deposited in the Gene Expression Omnibus (GEO) under accession numbers GSE162404 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE162404).
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Revealing the molecular mechanism of mouse innate behavior by single-cell sequencingNCBI Gene Expression Omnibus, GSE162404.
Article and author information
Author details
Funding
Ministry of Science and Technology of the People's Republic of China (2019YFA0110100; 2017YFA0103303)
- Xiaoqun Wang
Ministry of Science and Technology of the People's Republic of China (2017YFA0102601)
- Qian Wu
Chinese Academy of Sciences (XDB32010100)
- Xiaoqun Wang
National Natural Science Foundation of China (31925019)
- Peng Cao
National Natural Science Foundation of China (31771140; 81891001)
- Xiaoqun Wang
BUAA-CCMU Big Data and Precision Medicine Advanced Innovation Center Project (BHME-2019001)
- Xiaoqun Wang
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 experimental procedures were conducted following protocols approved by the Administrative Panel on Laboratory Animal Care at the National Institute of Biological Sciences, Beijing (NIBS) (NIBS2021M0006) and Institute of Biophysics, Chinese Academy of Sciences (SYXK2019015).
Copyright
© 2021, Xie 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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