Cargando…
Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2
BACKGROUND: Adult neurogenesis continuously adds new neurons to the dentate gyrus and the olfactory bulb. It involves the proliferation and subsequent differentiation of neuronal progenitors, and is thus closely linked to the cell cycle machinery. Cell cycle progression is governed by the successive...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
BioMed Central
2012
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3403990/ https://www.ncbi.nlm.nih.gov/pubmed/22564330 http://dx.doi.org/10.1186/1471-2202-13-46 |
_version_ | 1782238963933642752 |
---|---|
author | Ansorg, Anne Witte, Otto W Urbach, Anja |
author_facet | Ansorg, Anne Witte, Otto W Urbach, Anja |
author_sort | Ansorg, Anne |
collection | PubMed |
description | BACKGROUND: Adult neurogenesis continuously adds new neurons to the dentate gyrus and the olfactory bulb. It involves the proliferation and subsequent differentiation of neuronal progenitors, and is thus closely linked to the cell cycle machinery. Cell cycle progression is governed by the successive expression, activation and degradation of regulatory proteins. Among them, D-type cyclins control the exit from the G(1) phase of the cell cycle. Cyclin D2 (cD2) has been shown to be required for the generation of new neurons in the neurogenic niches of the adult brain. It is differentially expressed during hippocampal development, and adult cD2 knock out (cD2KO) mice virtually lack neurogenesis in the dentate gyrus and olfactory bulb. In the present study we examined the dynamics of postnatal and adult neurogenesis in the dentate gyrus (DG) of cD2KO mice. Animals were injected with bromodeoxyuridine at seven time points during the first 10 months of life and brains were immunohistochemically analyzed for their potential to generate new neurons. RESULTS: Compared to their WT litters, cD2KO mice had considerably reduced numbers of newly born granule cells during the postnatal period, with neurogenesis becoming virtually absent around postnatal day 28. This was paralleled by a reduction in granule cell numbers, in the volume of the granule cell layer as well as in apoptotic cell death. CD2KO mice did not show any of the age-related changes in neurogenesis and granule cell numbers that were seen in WT litters. CONCLUSIONS: The present study suggests that hippocampal neurogenesis becomes increasingly dependent on cD2 during early postnatal development. In cD2KO mice, hippocampal neurogenesis ceases at a time point at which the tertiary germinative matrix stops proliferating, indicating that cD2 becomes an essential requirement for ongoing neurogenesis with the transition from developmental to adult neurogenesis. Our data further support the notion that adult neurogenesis continuously adds new neurons to the hippocampal network, hence increasing cell density of the DG. |
format | Online Article Text |
id | pubmed-3403990 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | BioMed Central |
record_format | MEDLINE/PubMed |
spelling | pubmed-34039902012-07-25 Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 Ansorg, Anne Witte, Otto W Urbach, Anja BMC Neurosci Research Article BACKGROUND: Adult neurogenesis continuously adds new neurons to the dentate gyrus and the olfactory bulb. It involves the proliferation and subsequent differentiation of neuronal progenitors, and is thus closely linked to the cell cycle machinery. Cell cycle progression is governed by the successive expression, activation and degradation of regulatory proteins. Among them, D-type cyclins control the exit from the G(1) phase of the cell cycle. Cyclin D2 (cD2) has been shown to be required for the generation of new neurons in the neurogenic niches of the adult brain. It is differentially expressed during hippocampal development, and adult cD2 knock out (cD2KO) mice virtually lack neurogenesis in the dentate gyrus and olfactory bulb. In the present study we examined the dynamics of postnatal and adult neurogenesis in the dentate gyrus (DG) of cD2KO mice. Animals were injected with bromodeoxyuridine at seven time points during the first 10 months of life and brains were immunohistochemically analyzed for their potential to generate new neurons. RESULTS: Compared to their WT litters, cD2KO mice had considerably reduced numbers of newly born granule cells during the postnatal period, with neurogenesis becoming virtually absent around postnatal day 28. This was paralleled by a reduction in granule cell numbers, in the volume of the granule cell layer as well as in apoptotic cell death. CD2KO mice did not show any of the age-related changes in neurogenesis and granule cell numbers that were seen in WT litters. CONCLUSIONS: The present study suggests that hippocampal neurogenesis becomes increasingly dependent on cD2 during early postnatal development. In cD2KO mice, hippocampal neurogenesis ceases at a time point at which the tertiary germinative matrix stops proliferating, indicating that cD2 becomes an essential requirement for ongoing neurogenesis with the transition from developmental to adult neurogenesis. Our data further support the notion that adult neurogenesis continuously adds new neurons to the hippocampal network, hence increasing cell density of the DG. BioMed Central 2012-05-07 /pmc/articles/PMC3403990/ /pubmed/22564330 http://dx.doi.org/10.1186/1471-2202-13-46 Text en Copyright ©2012 Ansorg et al.; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Research Article Ansorg, Anne Witte, Otto W Urbach, Anja Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 |
title | Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 |
title_full | Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 |
title_fullStr | Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 |
title_full_unstemmed | Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 |
title_short | Age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin D2 |
title_sort | age-dependent kinetics of dentate gyrus neurogenesis in the absence of cyclin d2 |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3403990/ https://www.ncbi.nlm.nih.gov/pubmed/22564330 http://dx.doi.org/10.1186/1471-2202-13-46 |
work_keys_str_mv | AT ansorganne agedependentkineticsofdentategyrusneurogenesisintheabsenceofcyclind2 AT witteottow agedependentkineticsofdentategyrusneurogenesisintheabsenceofcyclind2 AT urbachanja agedependentkineticsofdentategyrusneurogenesisintheabsenceofcyclind2 |