Region-specific expression of cell cycle inhibitors in the adult brain.
In the adult brain, neural proliferation is almost absent and neurons are generally not renewed. By contrast, in the olfactory organ, olfactory neurons are produced continuously throughout life. To investigate whether specific cell cycle inhibitors are involved in the control of neural quiescence in adulthood, we compared their expression either in different regions of the adult brain weakly or non neurogenic or, for comparison, in the olfactory mucosa. We show that numerous cell cycle inhibitors are expressed in the adult brain either in an ubiquitous fashion (as p19Ink4d) or in specific brain regions (p15Ink4b in the forebrain, p27Kip1 and p21Cip1 in the cerebellum). By contrast p18Ink4c was expressed detectably only in the highly neurogenic olfactory epithelium. The present data suggest that various CDK inhibitors may be involved in a region-specific fashion in the maintenance of nerve cell quiescence in adults.
Legrier
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ME
Laboratoire de neurosciences, EA481, Université de Franche-Comté, 25030 Besançon Cedex, France.
Ducray
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Propper
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Kastner
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D000375:Aging / Q000235:genetics*; D000818:Animals; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D001923:Brain Chemistry / Q000235:genetics*; D002453:Cell Cycle / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D050762:Cyclin-Dependent Kinase Inhibitor p15; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism; D050763:Cyclin-Dependent Kinase Inhibitor p18; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D016213:Cyclins / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism; D019922:GAP-43 Protein / Q000378:metabolism; D015870:Gene Expression / Q000502:physiology*; D007150:Immunohistochemistry; D051379:Mice; D009474:Neurons / Q000378:metabolism; D009831:Olfactory Mucosa / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism
C493957:Cdkn1a protein, mouse; C493961:Cdkn1b protein, mouse; C493968:Cdkn2b protein, mouse; C493972:Cdkn2c protein, mouse; D018797:Cell Cycle Proteins; D050762:Cyclin-Dependent Kinase Inhibitor p15; D019941:Cyclin-Dependent Kinase Inhibitor p16; D050763:Cyclin-Dependent Kinase Inhibitor p18; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D019922:GAP-43 Protein; D018809:Proliferating Cell Nuclear Antigen; D014404:Tubulin; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases