Articles by Hisato Maruoka in JoVE
Large-scale Three-dimensional Imaging of Cellular Organization in the Mouse Neocortex Taisuke Yoneda1, Seiichiro Sakai1,2, Hisato Maruoka1, Toshihiko Hosoya1 1RIKEN Brain Science Institute, 2Tokyo Metropolitan Institute of Medical Science Here we describe a procedure for tissue clearing, fluorescent labeling, and large-scale imaging of mouse brain tissue which, thereby, enables visualization of the three-dimensional organization of cell types in the neocortex.
Other articles by Hisato Maruoka on PubMed
Periodic Organization of a Major Subtype of Pyramidal Neurons in Neocortical Layer V The Journal of Neuroscience : the Official Journal of the Society for Neuroscience. Dec, 2011 | Pubmed ID: 22171052 A major question in neocortical research is the extent to which neuronal organization is stereotyped. Previous studies have revealed functional clustering and neuronal interactions among cortical neurons located within tens of micrometers in the tangential orientation (orientation parallel to the pial surface). In the tangential orientation at this scale, however, it is unknown whether the distribution of neuronal subtypes is random or has any stereotypy. We found that the tangential arrangement of subcerebral projection neurons, which are a major pyramidal neuron subtype in mouse layer V, was not random but significantly periodic. This periodicity, which was observed in multiple cortical areas, had a typical wavelength of 30 μm. Under specific visual stimulation, neurons in single repeating units exhibited strongly correlated c-Fos expression. Therefore, subcerebral projection neurons have a periodic arrangement, and neuronal activity leading to c-Fos expression is similar among neurons in the same repeating units. These results suggest that the neocortex has a periodic functional micro-organization composed of a major neuronal subtype in layer V.
Lattice System of Functionally Distinct Cell Types in the Neocortex Science (New York, N.Y.). 11, 2017 | Pubmed ID: 29097542 The mammalian neocortex contains many cell types, but whether they organize into repeated structures has been unclear. We discovered that major cell types in neocortical layer 5 form a lattice structure in many brain areas. Large-scale three-dimensional imaging revealed that distinct types of excitatory and inhibitory neurons form cell type-specific radial clusters termed microcolumns. Thousands of microcolumns, in turn, are patterned into a hexagonal mosaic tessellating diverse regions of the neocortex. Microcolumn neurons demonstrate synchronized in vivo activity and visual responses with similar orientation preference and ocular dominance. In early postnatal development, microcolumns are coupled by cell type-specific gap junctions and later serve as hubs for convergent synaptic inputs. Thus, layer 5 neurons organize into a brainwide modular system, providing a template for cortical processing.