title: Dysfunction of the ubiquitin-proteasome system in the cerebellum of aging Ts65Dn mice.
abstract: In the cerebellum of adult-aging Ts65Dn mice, a murine model of Down syndrome, Purkinje cells undergo degeneration. Searching for the cause of Purkinje cell degeneration, we have studied the ubiquitin-proteasome system (UPS) in the cerebellum of aging Ts65Dn mice. Inhibition of UPS is sufficient to induce neuron degeneration and death. Proteasome chymotrypsin-like proteolytic activity was reduced by 35% in the cerebellum of Ts65Dn mice in comparison with euploid animals. Accordingly, Western blot analysis of ubiquitin showed an increase in ubiquitinated proteins. Immunocytochemistry for ubiquitin revealed strongly positive intranuclear inclusions in Purkinje cells and large neurons of cerebellar nuclei. The Western blot analysis of ubiquitin in nuclear protein extracts confirmed the increase of ubiquitinated proteins in the cell nuclei. After FUS immunocytochemistry, large intranuclear inclusions were visible in Purkinje cells and large neurons of cerebellar nuclei in Ts65Dn mice. Together, data indicate a possible role for proteasome inhibition in the cerebellar neurodegeneration in Ts65Dn mice.
authors.affiliation: Dipartimento di Biologia Animale, Laboratorio di Biologia Cellulare e Neurobiologia, Università di Pavia, via Ferrata 1, 27100 Pavia, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Necchi
authors.forename: Selene
authors.initials: S
authors.lastname: Lomoio
authors.forename: Elda
authors.initials: E
authors.lastname: Scherini
mesh_terms: D000375:Aging / Q000378:metabolism / Q000473:pathology; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D002531:Cerebellum / Q000378:metabolism* / Q000473:pathology*; D004195:Disease Models, Animal; D004314:Down Syndrome / Q000378:metabolism* / Q000473:pathology*; D051379:Mice; D008818:Mice, Neurologic Mutants; D009410:Nerve Degeneration / Q000378:metabolism / Q000473:pathology; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D011689:Purkinje Cells / Q000378:metabolism / Q000473:pathology; D025801:Ubiquitin / Q000378:metabolism*; D054875:Ubiquitination / Q000502:physiology
chemical_list: D025801:Ubiquitin; D046988:Proteasome Endopeptidase Complex