Spine morphogenesis in newborn granule cells is differentially regulated in the outer and middle molecular layers

Abstract Glutamatergic mossy cells (MCs) are responsible for the associational and commissural connectivity of the dentate gyrus. MCs are widely distributed along the dorsoventral axis, but potential heterogeneity within MCs is scarcely explored. Here, we showed that MCs consist of two subpopulations which differ in their neuronal properties and functions. We discovered that MCs, depending on their dorsoventral location, extend distinct axonal projections in the molecular layers. Comparative transcriptional profiling of dorsal and ventral MCs revealed different neurobiological characteristics in axon guidance and synapse assembly. Despite common activation by external stimuli, dorsal MCs, but not ventral MCs, provide net inhibitory control on granule cells across the longitudinal axis. Furthermore, dorsal MC inhibition, unlikely that of ventral MCs, increases behavioral anxiety and disables rapid contextual discrimination. Collectively, dorsoventral heterogeneity of MCs may provide a novel mechanism for functional differentiation as well as distinct association along the longitudinal extent of the hippocampus.

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Neuronal localization of GAS7 within human brain tissue: Implications for schizophrenia research

Neurology International ◽

10.4081/ni.2018.7563 ◽

2018 ◽

Vol 10 (4) ◽

Cited By ~ 1

Author(s):

Michael A. Meyer

Keyword(s):

Cerebral Cortex ◽

Human Brain ◽

Brain Tissue ◽

Granule Cells ◽

Molecular Data ◽

Histochemical Localization ◽

Human Brain Tissue ◽

Sequencing Studies ◽

Normal Human ◽

Molecular Layers

In view of recent data on the linkage of Gas7 protein to schizophrenia, and in view of its role in neurite outgrowth, histochemical localization of the Gas7 protein was studied in normal human brain tissue using an online tissue atlas. Selective localization to neurons in the cerebral cortex was found with moderate levels in the hippocampus and caudate, but fairly low levels were noted within the human cerebellum and was limited to small granule cells as well as the neuropil of the cerebellar molecular layers. Despite this low intensity histochemical localization in the cerebellum, molecular data indicate a substantially large number of RNA transcripts in the cerebellum that exceeded the cerebral cortex as determined by sequencing studies.

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Brainstem projections to molecular layer heterotopia of the cerebellar vermis: Evidence from the Allen Mouse Brain Connectivity Database

10.7287/peerj.preprints.562 ◽

2014 ◽

Author(s):

Raddy L Ramos

Keyword(s):

Granule Cells ◽

Vestibular Nucleus ◽

Brain Connectivity ◽

Present Report ◽

Molecular Layer ◽

Dorsal Cochlear Nucleus ◽

Cerebellar Vermis ◽

Axonal Projections ◽

Viii And Ix ◽

Molecular Layers

Molecular layer heterotopia of the cerebellar vermis are a characteristic feature of C57BL/6 mice. Heterotopia consist of neurons and glia in the molecular layers between folia VIII and IX in regions lacking pia. Previously, we described the cellular composition of heterotopia which includes granule cells, Purkinje cells, Golgi cells, etc. However, the axonal constituents and afferent connections of these malformations remain poorly understood. In the present report axonal projections to heterotopia are documented from diverse brainstem nuclei such as the spinal vestibular nucleus, dorsal cochlear nucleus, and nucleus prepositus. These findings are relevant toward understanding the mechanisms of normal and abnormal cerebellar development and the establishment of cerebellar circuits.

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Brainstem projections to molecular layer heterotopia of the cerebellar vermis: Evidence from the Allen Mouse Brain Connectivity Database

10.7287/peerj.preprints.562v1 ◽

2014 ◽

Author(s):

Raddy L Ramos

Keyword(s):

Granule Cells ◽

Vestibular Nucleus ◽

Brain Connectivity ◽

Present Report ◽

Molecular Layer ◽

Dorsal Cochlear Nucleus ◽

Cerebellar Vermis ◽

Axonal Projections ◽

Viii And Ix ◽

Molecular Layers

Molecular layer heterotopia of the cerebellar vermis are a characteristic feature of C57BL/6 mice. Heterotopia consist of neurons and glia in the molecular layers between folia VIII and IX in regions lacking pia. Previously, we described the cellular composition of heterotopia which includes granule cells, Purkinje cells, Golgi cells, etc. However, the axonal constituents and afferent connections of these malformations remain poorly understood. In the present report axonal projections to heterotopia are documented from diverse brainstem nuclei such as the spinal vestibular nucleus, dorsal cochlear nucleus, and nucleus prepositus. These findings are relevant toward understanding the mechanisms of normal and abnormal cerebellar development and the establishment of cerebellar circuits.

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Ultrasturcture of cerebellar cells and neuropil in rats subjected to partial global cerebral ischemia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014227x ◽

1986 ◽

Vol 44 ◽

pp. 126-127

Author(s):

R.V.W. Dimlich ◽

M.H. Biros

Keyword(s):

Purkinje Cells ◽

Glial Cells ◽

Granule Cells ◽

Molecular Layer ◽

Cell Types ◽

Primary Objective ◽

Global Cerebral Ischemia ◽

Forebrain Ischemia ◽

Substantial Evidence ◽

Cerebellar Cells

Although a previous study in this laboratory determined that Purkinje cells of the rat cerebellum did not appear to be damaged following 30 min of forebrain ischemia followed by 30 min of reperfusion, it was suggested that an increase in rough endoplasmic reticulum (RER) and/or polysomes had occurred in these cells. The primary objective of the present study was to morphometrically determine whether or not this increase had occurred. In addition, since there is substantial evidence that glial cells may be affected by ischemia earlier than other cell types, glial cells also were examined. To ascertain possible effects on other cerebellar components, granule cells and neuropil near Purkinje cells as well as neuropil in the molecular layer also were evaluated in this investigation.

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Effects of aging on axon terminals in the dentate molecular layer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128924 ◽

1987 ◽

Vol 45 ◽

pp. 928-929

Author(s):

K. Cullen-Dockstader ◽

E. Fifkova

Keyword(s):

Granule Cells ◽

Molecular Layer ◽

Age Groups ◽

Long Term Potentiation ◽

Male Rats ◽

Perforant Path ◽

Axon Terminals ◽

Fischer 344 ◽

Spatial Memory Deficit ◽

Effects Of Aging

Normal aging results in a pronounced spatial memory deficit associated with a rapid decay of long-term potentiation at the synapses between the perforant path and spines in the medial and distal thirds of the dentate molecular layer (DML), suggesting the alteration of synaptic transmission in the dentate fascia. While the number of dentate granule cells remains unchanged, and there are no obvious pathological changes in these cells associated with increasing age, the density of their axospinous contacts has been shown to decrease. There are indications that the presynaptic element is affected by senescence before the postsynaptic element, yet little attention has been given to the fine structure of the remaining axon terminals. Therefore, we studied the axon terminals of the perforant path in the DML across three age groups.5 Male rats (Fischer 344) of each age group (3, 24 and 30 months), were perfused through the aorta.

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