Search results for "reelin"
showing 10 items of 12 documents
Neurochemical Phenotype of Reelin Immunoreactive Cells in the Piriform Cortex Layer II
2016
Reelin, a glycoprotein expressed by Cajal-Retzius neurons throughout the marginal layer of developing neocortex, has been extensively shown to play an important role during brain development, guiding neuronal migration and detachment from radial glia. During the adult life, however, many studies have associated Reelin expression to enhanced neuronal plasticity. Although its mechanism of action in the adult brain remains mostly unknown, Reelin is expressed mainly by a subset of mature interneurons. Here, we confirm the described phenotype of this subpopulation in the adult neocortex. We show that these mature interneurons, although being in close proximity, lack polysialylated neural cell ad…
Endothelial Dab1 signaling orchestrates neuro-glia-vessel communication in the central nervous system.
2018
Developing the bloodbrain barrier During development, signals need to be dynamically integrated by endothelial cells, neurons, and glia to achieve functional neuro-glia-vascular units in the central nervous system. During cortical development, neuronal Dab1 and ApoER2 receptors respond to a guidance cue called reelin. Studying mice, Segarra et al. found that Dab1 and ApoER2 are also expressed in endothelial cells (see the Perspective by Thomas). The integration of reelin signaling in endothelial cells and neurons facilitates the communication between vessels, glia, and neurons that is necessary for the correct positioning of neurons during cortical development. This integration is also impo…
Alterations in reelin and reelin receptors in Down syndrome.
2019
Reelin is an extracellular matrix glycoprotein that modulates synaptic function and plasticity, with a crucial role in neuronal migration. Changes in the expression of this protein have been reported in neurodegenerative diseases, such as Alzheimer's disease (AD). This molecule is produced by Cajal-Retzius neurons during development and by inhibitory neurons in the adult nervous system. Individuals with Down syndrome (DS) present an early development of AD; therefore, we analyzed the alterations in this molecule and its receptors in the murine model for DS Ts65Dn as well as in human with DS. We performed immunofluorescence analysis for reelin and its receptors very-low-density lipoprotein r…
Altered morphological and electrophysiological properties of Cajal-Retzius cells in cerebral cortex of embryonic Presenilin-1 knockout mice
2004
Mutations of Presenilin-1 are the major cause of familial Alzheimer's disease. Presenilin-1 knockout (PS1-/-) mice develop severe cortical dysplasia related to human type 2 lissencephaly. This overmigration syndrome has been attributed to the premature loss of Cajal-Retzius cells (CRcs), pioneer neurons required for the termination of radial neuronal migration. To elucidate the potential cellular mechanisms responsible for this premature neuronal loss, we investigated the morphological and electrophysiological properties of visually identified CRcs of wild-type (WT) and PS1-/- mouse brains at embryonic day 16.5. The density of CRcs was substantially reduced in the cerebral cortex of PS1-/-.…
Cajal–Retzius and subplate cells: transient cortical neurons and circuits with long-term impact
2020
Abstract The laminar and columnar organization of the mature cerebral cortex is determined by a variety of early developmental processes. Two distinct populations of early generated neurons play important roles in corticogenesis. Cajal–Retzius neurons, located in the marginal zone (later layer 1), control the formation of neocortical layers by releasing the extracellular matrix protein reelin, which serves as a guiding signal for migrating neurons. Subplate neurons in the lower neocortical layer play an active role in axonal pathfinding of thalamocortical connections and in transient synaptic circuits, influence early cortical plasticity and the maturation of the columnar architecture. Both…
Early life stress stimulates hippocampal reelin gene expression in a sex-specific manner: Evidence for corticosterone-mediated action
2010
Early life stress predisposes to the development of psychiatric disorders. In this context the hippocampal formation is of particular interest, because it is affected by stress on the structural and cognitive level. Since little is known how early life stress is translated on the molecular level, we mimicked early life stress in mouse models and analyzed the expression of the glycoprotein Reelin, a master molecule for development and differentiation of the hippocampus. From postnatal day 1 (P1) to P14, mouse pups were subjected to one of the following treatments: nonhandling (NH), handling (H), maternal separation (MS), and early deprivation (ED) followed by immediate (P15) or delayed (P70)…
Reelin expression in human prostate cancer: a marker of tumor aggressiveness based on correlation with grade
2007
Reelin is a glycoprotein that plays a critical role in the regulation of neuronal migration during brain development and, since reelin has a role in the control of cell migration, it might represents an important factor in cancer pathology. In this study, 66 surgical specimens of prostate cancer were analyzed for reelin expression by immunohistochemical method. The reelin expression was correlated with Gleason score and individual Gleason patterns. Reelin expression was found in 39% prostate cancers. Stromal tissues, normal epithelial cells and prostate intraepithelial neoplasia (PIN) of any grade around and distant from cancer were always negative for reelin. Reelin was found in malignant …
Cajal–Retzius cells: Update on structural and functional properties of these mystic neurons that bridged the 20th century
2014
Cajal-Retzius cells (CRc) represent a mostly transient neuronal cell type localized in the uppermost layer of the developing neocortex. The observation that CRc are a major source of the extracellular matrix protein reelin, which is essential for the laminar development of the cerebral cortex, attracted the interest in this unique cell type. In this review we will (i) describe the morphological and molecular properties of neocortical CRc, with a special emphasize on the question which markers can be used to identify CRc, (ii) summarize reports that identified the different developmental origins of CRc, (iii) discuss the fate of CRc, including recent evidence for apoptotic cell death and a p…
Reelin and CXCL12 regulate distinct migratory behaviors during the development of the dopaminergic system.
2014
The proper functioning of the dopaminergic system requires the coordinated formation of projections extending from dopaminergic neurons in the substantia nigra (SN), ventral tegmental area (VTA) and retrorubral field to a wide array of forebrain targets including the striatum, nucleus accumbens and prefrontal cortex. The mechanisms controlling the assembly of these distinct dopaminergic cell clusters are not well understood. Here, we have investigated in detail the migratory behavior of dopaminergic neurons giving rise to either the SN or the medial VTA using genetic inducible fate mapping, ultramicroscopy, time-lapse imaging, slice culture and analysis of mouse mutants. We demonstrate that…
The multiple facets of Cajal-Retzius neurons.
2021
ABSTRACTCajal-Retzius neurons (CRs) are among the first-born neurons in the developing cortex of reptiles, birds and mammals, including humans. The peculiarity of CRs lies in the fact they are initially embedded into the immature neuronal network before being almost completely eliminated by cell death at the end of cortical development. CRs are best known for controlling the migration of glutamatergic neurons and the formation of cortical layers through the secretion of the glycoprotein reelin. However, they have been shown to play numerous additional key roles at many steps of cortical development, spanning from patterning and sizing functional areas to synaptogenesis. The use of genetic l…