Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice
Abstract Entorhinal cortical (EC)-hippocampal (HPC) circuits are crucial for learning and memory. Although it was traditionally believed that superficial layers (II/III) of the EC mainly project to the HPC and deep layers (V/VI) receive input from the HPC, recent studies have highlighted the signifi...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2024-02-01
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| Series: | Molecular Brain |
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| Online Access: | https://doi.org/10.1186/s13041-024-01079-5 |
| _version_ | 1827325767836499968 |
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| author | Naoki Yamamoto Jun Yokose Kritika Ramesh Takashi Kitamura Sachie K. Ogawa |
| author_facet | Naoki Yamamoto Jun Yokose Kritika Ramesh Takashi Kitamura Sachie K. Ogawa |
| author_sort | Naoki Yamamoto |
| collection | DOAJ |
| description | Abstract Entorhinal cortical (EC)-hippocampal (HPC) circuits are crucial for learning and memory. Although it was traditionally believed that superficial layers (II/III) of the EC mainly project to the HPC and deep layers (V/VI) receive input from the HPC, recent studies have highlighted the significant projections from layers Va and VI of the EC into the HPC. However, it still remains unknown whether Vb neurons in the EC provide projections to the hippocampus. In this study, using a molecular marker for Vb and retrograde tracers, we identified that the outer layer of Vb neurons in the medial EC (MEC) directly project to both dorsal and ventral hippocampal dentate gyrus (DG), with a significant preference for the ventral DG. In contrast to the distribution of DG-projecting Vb cells, anterior thalamus-projecting Vb cells are distributed through the outer to the inner layer of Vb. Furthermore, dual tracer injections revealed that DG-projecting Vb cells and anterior thalamus-projecting Vb cells are distinct populations. These results suggest that the roles of MEC Vb neurons are not merely limited to the formation of EC-HPC loop circuits, but rather contribute to multiple neural processes for learning and memory. |
| first_indexed | 2024-03-07T14:34:08Z |
| format | Article |
| id | doaj.art-945d2834cfe84a068db85fd139e3e13e |
| institution | Directory Open Access Journal |
| issn | 1756-6606 |
| language | English |
| last_indexed | 2024-03-07T14:34:08Z |
| publishDate | 2024-02-01 |
| publisher | BMC |
| record_format | Article |
| series | Molecular Brain |
| spelling | doaj.art-945d2834cfe84a068db85fd139e3e13e2024-03-05T20:44:34ZengBMCMolecular Brain1756-66062024-02-011711510.1186/s13041-024-01079-5Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in miceNaoki Yamamoto0Jun Yokose1Kritika Ramesh2Takashi Kitamura3Sachie K. Ogawa4Department of Psychiatry, University of Texas Southwestern Medical CenterDepartment of Psychiatry, University of Texas Southwestern Medical CenterDepartment of Psychiatry, University of Texas Southwestern Medical CenterDepartment of Psychiatry, University of Texas Southwestern Medical CenterDepartment of Psychiatry, University of Texas Southwestern Medical CenterAbstract Entorhinal cortical (EC)-hippocampal (HPC) circuits are crucial for learning and memory. Although it was traditionally believed that superficial layers (II/III) of the EC mainly project to the HPC and deep layers (V/VI) receive input from the HPC, recent studies have highlighted the significant projections from layers Va and VI of the EC into the HPC. However, it still remains unknown whether Vb neurons in the EC provide projections to the hippocampus. In this study, using a molecular marker for Vb and retrograde tracers, we identified that the outer layer of Vb neurons in the medial EC (MEC) directly project to both dorsal and ventral hippocampal dentate gyrus (DG), with a significant preference for the ventral DG. In contrast to the distribution of DG-projecting Vb cells, anterior thalamus-projecting Vb cells are distributed through the outer to the inner layer of Vb. Furthermore, dual tracer injections revealed that DG-projecting Vb cells and anterior thalamus-projecting Vb cells are distinct populations. These results suggest that the roles of MEC Vb neurons are not merely limited to the formation of EC-HPC loop circuits, but rather contribute to multiple neural processes for learning and memory.https://doi.org/10.1186/s13041-024-01079-5Medial entorhinal cortexHippocampusAnterior thalamusLearningMemoryCtip2 |
| spellingShingle | Naoki Yamamoto Jun Yokose Kritika Ramesh Takashi Kitamura Sachie K. Ogawa Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice Molecular Brain Medial entorhinal cortex Hippocampus Anterior thalamus Learning Memory Ctip2 |
| title | Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice |
| title_full | Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice |
| title_fullStr | Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice |
| title_full_unstemmed | Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice |
| title_short | Outer layer of Vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice |
| title_sort | outer layer of vb neurons in medial entorhinal cortex project to hippocampal dentate gyrus in mice |
| topic | Medial entorhinal cortex Hippocampus Anterior thalamus Learning Memory Ctip2 |
| url | https://doi.org/10.1186/s13041-024-01079-5 |
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