Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur Graph Search.
Concept
Subgranular zone
Résumé
The subgranular zone (SGZ) is a brain region in the hippocampus where adult neurogenesis occurs. The other major site of adult neurogenesis is the subventricular zone (SVZ) in the brain.
The subgranular zone is a narrow layer of cells located between the granule cell layer and hilus of the dentate gyrus. This layer is characterized by several types of cells, the most prominent type being neural stem cells (NSCs) in various stages of development. However, in addition to NSCs, there are also astrocytes, endothelial cells, blood vessels, and other components, which form a microenvironment that supports the NSCs and regulates their proliferation, migration, and differentiation. The discovery of this complex microenvironment and its crucial role in NSC development has led some to label it as a neurogenic “niche”. It is also frequently referred to as a vascular, or angiogenic, niche due to the importance and pervasiveness of the blood vessels in the SGZ.
The brain comprises many different types of neurons, but the SGZ generates only one type: granule cells—the primary excitatory neurons in the dentate gyrus (DG)--which are thought to contribute to cognitive functions such as memory and learning. The progression from neural stem cell to granule cell in the SGZ can be described by tracing the following lineage of cell types:
Radial glial cells. Radial glial cells are a subset of astrocytes, which are typically thought of as non-neuronal support cells. The radial glial cells in the SGZ have cell bodies that reside in the SGZ and vertical (or radial) processes that extend into the molecular layer of the DG. These processes act as a scaffold upon which newly formed neurons can migrate the short distance from the SGZ to the granule cell layer. Radial glia are astrocytic in their morphology, their expression of glial markers such as GFAP, and their function in regulating the NSC microenvironment. However, unlike most astrocytes, they also act as neurogenic progenitors; in fact, they are widely considered to be the neural stem cells that give rise to subsequent neuronal precursor cells.
Source officielle
À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.