Details

Autor(en) / Beteiligte

• Kim, Catherine D.
• Reed, Ryan E.
• Juncker, Meredith A.
• Fang, Zhide
• Desai, Shyamal D.

Titel

Evidence for the Deregulation of Protein Turnover Pathways in Atm-Deficient Mouse Cerebellum: An Organotypic Study

Ist Teil von

• Journal of neuropathology and experimental neurology, 2017-07, Vol.76 (7), p.578-584

Ort / Verlag

England: Oxford University Press

Erscheinungsjahr

2017

Quelle

Oxford Journals 2020 Medicine

Beschreibungen/Notizen

• Abstract Interferon-stimulated gene 15 (ISG15), an antagonist of the ubiquitin pathway, is elevated in cells and brain tissues obtained from ataxia telangiectasia (A-T) patients. Previous studies reveal that an elevated ISG15 pathway inhibits ubiquitin-dependent protein degradation, leading to activation of basal autophagy as a compensatory mechanism for protein turnover in A-T cells. Also, genotoxic stress (ultraviolet [UV] radiation) deregulates autophagy and induces aberrant degradation of ubiquitylated proteins in A-T cells. In the current study, we show that, as in A-T cells, ISG15 protein expression is elevated in cerebellums and various other tissues obtained from Atm-compromised mice in an Atm-allele-dependent manner (Atm+/+  < Atm+/ − < Atm−/− ). Notably, in cerebellums, the brain part primarily affected in A-T, levels of ISG15 were significantly greater (3-fold higher) than cerebrums obtained from the same set of mice. Moreover, as in A-T cell culture, UV induces aberrant degradation of ubiquitylated proteins and autophagy in Atm-deficient, but not in Atm-proficient, cerebellar brain slices grown in culture. Thus, the ex vivo organotypic A-T mouse brain culture model mimics that of an A-T human cell culture model and could be useful for studying the role of ISG15-dependent proteinopathy in cerebellar neurodegeneration, a hallmark of A-T in humans.