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From Individual to Population: Circuit Organization of Pyramidal Tract and Intratelencephalic Neurons in Mouse Sensorimotor Cortex

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Specialty Biology
Date 2024 Oct 8
PMID 39376961
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Abstract

The sensorimotor cortex participates in diverse functions with different reciprocally connected subregions and projection-defined pyramidal neuron types therein, while the fundamental organizational logic of its circuit elements at the single-cell level is still largely unclear. Here, using mouse Cre driver lines and high-resolution whole-brain imaging to selectively trace the axons and dendrites of cortical pyramidal tract (PT) and intratelencephalic (IT) neurons, we reconstructed the complete morphology of 1,023 pyramidal neurons and generated a projectome of 6 subregions within the sensorimotor cortex. Our morphological data revealed substantial hierarchical and layer differences in the axonal innervation patterns of pyramidal neurons. We found that neurons located in the medial motor cortex had more diverse projection patterns than those in the lateral motor and sensory cortices. The morphological characteristics of IT neurons in layer 5 were more complex than those in layer 2/3. Furthermore, the soma location and morphological characteristics of individual neurons exhibited topographic correspondence. Different subregions and layers were composed of different proportions of projection subtypes that innervate downstream areas differentially. While the axonal terminals of PT neuronal population in each cortical subregion were distributed in specific subdomains of the superior colliculus (SC) and zona incerta (ZI), single neurons selectively innervated a combination of these projection targets. Overall, our data provide a comprehensive list of projection types of pyramidal neurons in the sensorimotor cortex and begin to unveil the organizational principle of these projection types in different subregions and layers.

References
1.
Harrison T, Ayling O, Murphy T . Distinct cortical circuit mechanisms for complex forelimb movement and motor map topography. Neuron. 2012; 74(2):397-409. DOI: 10.1016/j.neuron.2012.02.028. View

2.
Barth T, Jones T, Schallert T . Functional subdivisions of the rat somatic sensorimotor cortex. Behav Brain Res. 1990; 39(1):73-95. DOI: 10.1016/0166-4328(90)90122-u. View

3.
Benavidez N, Bienkowski M, Zhu M, Garcia L, Fayzullina M, Gao L . Organization of the inputs and outputs of the mouse superior colliculus. Nat Commun. 2021; 12(1):4004. PMC: 8239028. DOI: 10.1038/s41467-021-24241-2. View

4.
Jensen K, Kadmon Harpaz N, Dhawale A, Wolff S, Olveczky B . Long-term stability of single neuron activity in the motor system. Nat Neurosci. 2022; 25(12):1664-1674. PMC: 11152193. DOI: 10.1038/s41593-022-01194-3. View

5.
Andrewes D, Jenkins L . The Role of the Amygdala and the Ventromedial Prefrontal Cortex in Emotional Regulation: Implications for Post-traumatic Stress Disorder. Neuropsychol Rev. 2019; 29(2):220-243. DOI: 10.1007/s11065-019-09398-4. View