Biology subjects

Dunville, K.

Publications and source records attributed to Dunville, K..

3 recordsLinked to original sources

bioRxiv2026

Spatial representation in CA1 superficial pyramidal cells is impaired after postnatal ablation of hippocampal Cajal Retzius cells

Cajal-Retzius neurons (CRs) are a transient cell type that populates the postnatal hippocampus. To test how the persistence of CRs shapes the maturation of hippocampal function, we used a CRs-specific transgenic mouse line combined with targeted viral delivery to selectively ablate CRs in the postnatal hippocampus. Single cell sequencing revealed that gene networks in superficial CA1 pyramidal cells were more strongly perturbed compared to deep CA1 pyramidal cells. To test if these two subpopulations were also distinctly affected in their function, we performed in vivo recordings from spatially modulated cells in CA1. Our analysis showed an impaired spatial representation specifically in superficial CA1 pyramidal cells. Additionally, we observed an increased CA3 to CA1 excitatory drive, as indicated by increased gamma oscillations, and alterations of intrinsic firing properties in superficial CA1 pyramidal neurons confirmed by in vitro electrophysiological recordings. Together, these results indicate a crucial role for CRs in the maturation of hippocampal subcircuits.

neuroscience↗

bioRxiv2022

Persistence of Cajal-Retzius cells in the postnatal hippocampus is required for development of dendritic spines of CA1 pyramidal cells

Cajal-Retzius (CR) cells are a transient type of neuron that populate the postnatal hippocampus. The role of transient cell types and circuits have been vastly addressed in neocortical regions, but poorly studied in the hippocampus. To understand how CR cells persistence influences the maturation of hippocampal circuits, we specifically ablated CR cells from the postnatal hippocampus. Our results highlighted layer-specific effects on dendritic spines and synaptic-related genes and revealed a critical role of CR cells in the establishment of the hippocampal network.

neuroscience↗

bioRxiv2020

An Eutherian-Specific microRNA Controls the Translation of Satb2 in a Model of Cortical Differentiation

Cerebral cortical development is controlled by key transcription factors that specify the neuronal identities in the different cortical layers. These transcription factors are crucial for the identity of the different neurons, but the mechanisms controlling their expression in distinct cells are only partially known. Here we investigate the expression and stability of the mRNAs of Tbr1, Bcl11b, Fezf2, Satb2 and Cux1 in single developing mouse cortical cells. We focus on Satb2 and find that its mRNA expression occurs much earlier than its protein synthesis and in a set of cells broader than expected, suggesting an initially tight control of its translation, which is subsequently de-repressed at late developmental stages. Mechanistically, Satb2 3UTR modulates protein translation of GFP reporters during mouse corticogenesis. By in vitro pull-down of Satb2 3UTR-associated miRNAs, we select putative miRNAs responsible for SATB2 inhibition, focusing on those strongly expressed in early progenitor cells and reduced in late cells. miR-541, an Eutherian-specific miRNA, and miR-92a/b are the best candidates and their inactivation triggers robust and premature SATB2 translation in both mouse and human cortical cells. Our findings indicate that RNA interference plays a major role in the timing of cortical cell identity and may be part of the toolkit involved in specifying supra-granular projection neurons.

developmental biology↗