Target-specific M1 inputs to infragranular S1 pyramidal neurons

The functional role of input from the primary motor cortex (M1) to primary somatosensory cortex (S1) is unclear; one key to understanding this pathway may lie in elucidating the cell-type specific microcircuits that connect S1 and M1. Recently, we discovered that a subset of pyramidal neurons in the infragranular layers of S1 receive especially strong input from M1 (Kinnischtzke AK, Simons DJ, Fanselow EE. Cereb Cortex 24: 2237–2248, 2014), suggesting that M1 may affect specific classes of pyramidal neurons differently. Here, using combined optogenetic and retrograde labeling approaches in the mouse, we examined the strengths of M1 inputs to five classes of infragranular S1 neurons categorized by their projections to particular cortical and subcortical targets. We found that the magnitude of M1 synaptic input to S1 pyramidal neurons varies greatly depending on the projection target of the postsynaptic neuron. Of the populations examined, M1-projecting corticocortical neurons in L6 received the strongest M1 inputs, whereas ventral posterior medial nucleus-projecting corticothalamic neurons, also located in L6, received the weakest. Each population also possessed distinct intrinsic properties. The results suggest that M1 differentially engages specific classes of S1 projection neurons, thereby regulating the motor-related influence S1 exerts over subcortical structures.

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High-order thalamic inputs to primary somatosensory cortex are stronger and longer lasting than cortical inputs

eLife ◽

10.7554/elife.44158 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 26

Author(s):

Wanying Zhang ◽

Randy M Bruno

Keyword(s):

Somatosensory Cortex ◽

Primary Motor Cortex ◽

Pyramidal Neurons ◽

Sensory Stimulation ◽

Primary Somatosensory Cortex ◽

Specific Substrate ◽

Medial Nucleus ◽

Posterior Medial Nucleus ◽

Cortical Inputs

Layer (L) 2/3 pyramidal neurons in the primary somatosensory cortex (S1) are sparsely active, spontaneously and during sensory stimulation. Long-range inputs from higher areas may gate L2/3 activity. We investigated their in vivo impact by expressing channelrhodopsin in three main sources of feedback to rat S1: primary motor cortex, secondary somatosensory cortex, and secondary somatosensory thalamic nucleus (the posterior medial nucleus, POm). Inputs from cortical areas were relatively weak. POm, however, more robustly depolarized L2/3 cells and, when paired with peripheral stimulation, evoked action potentials. POm triggered not only a stronger fast-onset depolarization but also a delayed all-or-none persistent depolarization, lasting up to 1 s and exhibiting alpha/beta-range oscillations. Inactivating POm somata abolished persistent but not initial depolarization, indicating a recurrent circuit mechanism. We conclude that secondary thalamus can enhance L2/3 responsiveness over long periods. Such timescales could provide a potential modality-specific substrate for attention, working memory, and plasticity.

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Synapses from the high-order thalamic nucleus and motor cortex are co-clustered in the distal tuft dendrites of the mouse somatosensory cortex

10.1101/2020.11.08.363200 ◽

2020 ◽

Author(s):

Nari Kim ◽

Sangkyu Bahn ◽

Joon Ho Choi ◽

Jinseop S. Kim ◽

Jong-Cheol Rah

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Pyramidal Neurons ◽

Barrel Cortex ◽

Essential Information ◽

Medial Nucleus ◽

Array Tomography ◽

Posterior Medial Nucleus ◽

Dendritic Branches ◽

Insight Into

ABSTRACTThe posterior medial nucleus of the thalamus (POm) and vibrissal primary motor cortex (vM1) convey essential information to the barrel cortex (S1BF) regarding whisker position and movement. Therefore, understanding the relative spatial relationships of these two inputs is critical prerequisites to acquire insight into how S1 synthesizes information to interpret the location of an object. Using array tomography, we identified the locations of synapses from vM1 and POm on distal tuft dendrites of L5 pyramidal neurons. We found that synapses from vM1 and POm are spatially clustered on the same set of dendrites with unusually high density. Furthermore, the clusters of vM1 and POm synapses colocalize each other. These findings suggest that synaptic clusters, but not dendritic branches, act as functional units and cooperatively contribute to nonlinear dendritic responses.

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Unique properties of high-order thalamic inputs versus cortical inputs to primary somatosensory cortex

10.1101/495218 ◽

2018 ◽

Author(s):

Elaine Zhang ◽

Randy M Bruno

Keyword(s):

Somatosensory Cortex ◽

Primary Motor Cortex ◽

Pyramidal Neurons ◽

Sensory Stimulation ◽

Primary Somatosensory Cortex ◽

Specific Substrate ◽

Medial Nucleus ◽

Posterior Medial Nucleus ◽

Cortical Inputs

Layer (L) 2/3 pyramidal neurons in the primary somatosensory cortex (S1) are sparsely active, spontaneously and during sensory stimulation. Long-range inputs from higher areas may gate L2/3 activity. We investigated their in vivo impact by expressing channelrhodopsin in three main sources of feedback to rat S1: primary motor cortex, secondary somatosensory cortex, and secondary somatosensory thalamic nucleus (the posterior medial nucleus, POm). Inputs from cortical areas were relatively weak. POm, however, more robustly depolarized L2/3 cells and, when paired with peripheral stimulation, evoked action potentials. POm triggered not only a stronger fast-onset depolarization but also a delayed all-or-none persistent depolarization, lasting up to 1 second and exhibiting beta oscillations. Inactivating POm somata abolished persistent but not initial depolarization, indicating a recurrent circuit mechanism. We conclude that secondary thalamus can enhance L2/3 responsiveness over long periods. Such timescales could provide a potential modality-specific substrate for attention, working memory, and plasticity.

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Connectivity characterization of the mouse basolateral amygdalar complex

Nature Communications ◽

10.1038/s41467-021-22915-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Houri Hintiryan ◽

Ian Bowman ◽

David L. Johnson ◽

Laura Korobkova ◽

Muye Zhu ◽

...

Keyword(s):

Granular Cell ◽

Cell Types ◽

Projection Neurons ◽

Cell Type ◽

Connectivity Map ◽

Analysis Techniques ◽

Domain Specific ◽

Cell Type Specific ◽

Unique Domain

AbstractThe basolateral amygdalar complex (BLA) is implicated in behaviors ranging from fear acquisition to addiction. Optogenetic methods have enabled the association of circuit-specific functions to uniquely connected BLA cell types. Thus, a systematic and detailed connectivity profile of BLA projection neurons to inform granular, cell type-specific interrogations is warranted. Here, we apply machine-learning based computational and informatics analysis techniques to the results of circuit-tracing experiments to create a foundational, comprehensive BLA connectivity map. The analyses identify three distinct domains within the anterior BLA (BLAa) that house target-specific projection neurons with distinguishable morphological features. We identify brain-wide targets of projection neurons in the three BLAa domains, as well as in the posterior BLA, ventral BLA, posterior basomedial, and lateral amygdalar nuclei. Inputs to each nucleus also are identified via retrograde tracing. The data suggests that connectionally unique, domain-specific BLAa neurons are associated with distinct behavior networks.

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The role of CpG methylation in cell type-specific expression of the aquaporin-5 gene

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2006.12.126 ◽

2007 ◽

Vol 353 (4) ◽

pp. 1017-1022 ◽

Cited By ~ 17

Author(s):

Johji Nomura ◽

Akinori Hisatsune ◽

Takeshi Miyata ◽

Yoichiro Isohama

Keyword(s):

Cpg Methylation ◽

Cell Type ◽

Aquaporin 5 ◽

Specific Expression ◽

Cell Type Specific Expression ◽

Cell Type Specific

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Presynaptic GABAB receptors differentially modulate GABA release from cholecystokinin and parvalbumin interneurons onto CA1 pyramidal neurons: a cell type-specific labeling and activating study

Neuroscience Letters ◽

10.1016/j.neulet.2022.136448 ◽

2022 ◽

pp. 136448

Author(s):

Caifeng Shao ◽

Jiaxue Dong ◽

Mingwei Zhao ◽

Shenhao Liu ◽

Xue Wang ◽

...

Keyword(s):

Pyramidal Neurons ◽

Gaba Release ◽

Gabab Receptors ◽

Cell Type ◽

Ca1 Pyramidal Neurons ◽

Parvalbumin Interneurons ◽

A Cell ◽

Cell Type Specific

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Periaqueductal efferents to dopamine and GABA neurons of the VTA

10.1101/117416 ◽

2017 ◽

Cited By ~ 1

Author(s):

Niels R. Ntamati ◽

Meaghan Creed ◽

Christian Lüscher

Keyword(s):

Functional Analysis ◽

Ventral Tegmental Area ◽

Periaqueductal Gray ◽

Retrograde Tracing ◽

The Other ◽

Projection Neurons ◽

Cell Type ◽

Gaba Neurons ◽

Other Hand ◽

Cell Type Specific

AbstractNeurons in the periaqueductal gray (PAG) modulate threat responses and nociception. Activity in the ventral tegmental area (VTA) on the other hand can cause reinforcement and aversion. While in many situations these behaviors are related, the anatomical substrate of a crosstalk between the PAG and VTA remains poorly understood. Here we describe the anatomical and electrophysiological organization of the VTA-projecting PAG neurons. Using rabies-based, cell type-specific retrograde tracing, we observed that PAG to VTA projection neurons are evenly distributed along the rostro-caudal axis of the PAG, but concentrated in its posterior and ventrolateral segments. Optogenetic projection targeting demonstrated that the PAG-to-VTA pathway is predominantly excitatory and targets similar proportions of Ih-expressing VTA DA and GABA neurons. Taken together, these results set the framework for functional analysis of the interplay between PAG and VTA in the regulation of reward and aversion.

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Faculty Opinions recommendation of Cell-Type-Specific Role of ΔFosB in Nucleus Accumbens In Modulating Intermale Aggression.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.733431968.793561598 ◽

2019 ◽

Author(s):

Klaus Miczek ◽

Herbert Covington III

Keyword(s):

Nucleus Accumbens ◽

Specific Role ◽

Cell Type ◽

Intermale Aggression ◽

Cell Type Specific

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Integration of signals from different cortical areas in higher order thalamic neurons

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2104137118 ◽

2021 ◽

Vol 118 (30) ◽

pp. e2104137118

Author(s):

Vandana Sampathkumar ◽

Andrew Miller-Hansen ◽

S. Murray Sherman ◽

Narayanan Kasthuri

Keyword(s):

Higher Order ◽

Cortical Layer ◽

Thalamic Neurons ◽

Cortical Areas ◽

Medial Nucleus ◽

Afferent Information ◽

Posterior Medial Nucleus ◽

Depth And Complexity ◽

Genetic Labeling

Higher order thalamic neurons receive driving inputs from cortical layer 5 and project back to the cortex, reflecting a transthalamic route for corticocortical communication. To determine whether or not individual neurons integrate signals from different cortical populations, we combined electron microscopy “connectomics” in mice with genetic labeling to disambiguate layer 5 synapses from somatosensory and motor cortices to the higher order thalamic posterior medial nucleus. A significant convergence of these inputs was found on 19 of 33 reconstructed thalamic cells, and as a population, the layer 5 synapses were larger and located more proximally on dendrites than were unlabeled synapses. Thus, many or most of these thalamic neurons do not simply relay afferent information but instead integrate signals as disparate in this case as those emanating from sensory and motor cortices. These findings add further depth and complexity to the role of the higher order thalamus in overall cortical functioning.

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