Cerebellar granule cells are predominantly generated by terminal symmetric divisions of granule cell precursors
K Nakashima, H Umeshima… - Developmental …, 2015 - Wiley Online Library
K Nakashima, H Umeshima, M Kengaku
Developmental Dynamics, 2015•Wiley Online LibraryBackground: Neurons in the central nervous system (CNS) are generated by symmetric and
asymmetric cell division of neural stem cells and their derivative progenitor cells. Cerebellar
granule cells are the most abundant neurons in the CNS, and are generated by intensive
cell division of granule cell precursors (GCPs) during postnatal development. Dysregulation
of GCP cell cycle is causal for some subtypes of medulloblastoma. However, the details and
mechanisms underlying neurogenesis from GCPs are not well understood. Results: Using …
asymmetric cell division of neural stem cells and their derivative progenitor cells. Cerebellar
granule cells are the most abundant neurons in the CNS, and are generated by intensive
cell division of granule cell precursors (GCPs) during postnatal development. Dysregulation
of GCP cell cycle is causal for some subtypes of medulloblastoma. However, the details and
mechanisms underlying neurogenesis from GCPs are not well understood. Results: Using …
Background: Neurons in the central nervous system (CNS) are generated by symmetric and asymmetric cell division of neural stem cells and their derivative progenitor cells. Cerebellar granule cells are the most abundant neurons in the CNS, and are generated by intensive cell division of granule cell precursors (GCPs) during postnatal development. Dysregulation of GCP cell cycle is causal for some subtypes of medulloblastoma. However, the details and mechanisms underlying neurogenesis from GCPs are not well understood. Results: Using long‐term live‐cell imaging of proliferating GCPs transfected with a fluorescent newborn‐granule cell marker, we found that GCPs underwent predominantly symmetric divisions, generating two GCPs or two neurons, while asymmetric divisions generating a GCP and a neuron were only occasionally observed, in both dissociated culture and within tissues of isolated cerebellar lobules. We found no significant difference in cell cycle length between proliferative and neurogenic divisions, or any consistent changes in cell cycle length during repeated proliferative division. Conclusions: Unlike neural stem cells in the cerebral cortex and spinal cord, which generate many neurons by repeated asymmetric division, cerebellar GCPs produce neurons predominantly by terminal symmetric division. These results indicate diverse mechanisms of neurogenesis in the mammalian brain. Developmental Dynamics 244:748–758, 2015. © 2015 Wiley Periodicals, Inc.
