BMI Seminar // Hidenobu Mizuno - Imaging neuronal morphology and activity pattern in developing cerebral cortex layer 4

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Event details

Date 27.10.2021 12:1513:15  
Speaker Hidenobu Mizuno, Kumamoto University, Japan
Location Online
Category Conferences - Seminars
Event Language English
IMPORTANT NOTICE:

In-person attendance of this seminar is subjected to some constraints:
  • Maximum number of participants is limited to 80
  • Valid COVID certificate and ID (e.g. Camipro card), required to enter the conference room, will be checked at the entrance
  • Face masks are mandatory for everyone in the seminar room (excepted the speaker while presenting).
Establishment of precise neuronal connectivity in the neocortex relies on activity-dependent circuit reorganization during postnatal development. In the mouse somatosensory cortex layer 4, barrels are arranged in one-to-one correspondence to whiskers on the face. Thalamocortical axon termini are clustered in the center of each barrel. The layer 4 spiny stellate neurons are located around the barrel edge, extend their dendrites primarily toward the barrel center, and make synapses with thalamocortical axons corresponding to a single whisker. These organized circuits are established during the first postnatal week through activity-dependent refinement processes. However, activity pattern regulating the circuit formation is still elusive. Using two-photon calcium imaging in living neonatal mice, we found that layer 4 neurons within the same barrel fire synchronously in the absence of peripheral stimulation, creating a ''patchwork'' pattern of spontaneous activity corresponding to the barrel map. We also found that disruption of GluN1, an obligatory subunit of the N-methyl-D-aspartate (NMDA) receptor, in a sparse population of layer 4 neurons reduced activity correlation between GluN1 knockout neuron pairs within a barrel. Our results provide evidence for the involvement of layer 4 neuron NMDA receptors in spatial organization of the spontaneous firing activity of layer 4 neurons in the neonatal barrel cortex. In the talk I will introduce our strategy to analyze the role of NMDA receptor-dependent correlated activity in the layer 4 circuit formation.
 

Practical information

  • Informed public
  • Free

Organizer

  • SV Brain Mind Institute Host : Carl Petersen

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