Conformational altered p53 affects neuronal function: relevance for the response to toxic insult and growth-associated protein 43 expression

• Published in: Cell death & disease 2013-02, Vol.4 (2), p.e484-e484
• Main Authors: Buizza, L, Prandelli, C, Bonini, S A, Delbarba, A, Cenini, G, Lanni, C, Buoso, E, Racchi, M, Govoni, S, Memo, M, Uberti, D
• Format: Article
• Language: English
• Subjects: 631/208/199; 631/378/2583; 631/80/82; 692/699/375/365/1283; Amyloid beta-Protein Precursor - genetics; Amyloid beta-Protein Precursor - metabolism; Antibodies; Biochemistry; Biomedical and Life Sciences; Cell Biology; Cell Culture; Cell Line, Tumor; Cell Survival - drug effects; Chlorides - pharmacology; GAP-43 Protein - genetics; GAP-43 Protein - metabolism; Humans; Hydrogen Peroxide - toxicity; Immunology; Life Sciences; Neurons - metabolism; Original; original-article; Oxidative Stress; Protein Structure, Tertiary; Protein Unfolding; RNA, Messenger - metabolism; Transcription, Genetic - drug effects; Tumor Suppressor Protein p53 - chemistry; Tumor Suppressor Protein p53 - metabolism; Tyrosine - analogs & derivatives; Tyrosine - chemistry; Zinc Compounds - pharmacology
• ISSN: 2041-4889; 2041-4889
• DOI: 10.1038/cddis.2013.13

The role of p53 in neurodegenerative diseases is essentially associated with neuronal death. Recently an alternative point of view is emerging, as altered p53 conformation and impaired protein function have been found in fibroblasts and blood cells derived from Alzheimer’s disease patients. Here, using stable transfected SH-SY5Y cells overexpressing APP751wt (SY5Y-APP) we demonstrated that the expression of an unfolded p53 conformation compromised neuronal functionality. In particular, these cells showed (i) augmented expression of amyloid precursor protein (APP) and its metabolites, including the C-terminal fragments C99 and C83 and β -amyloid peptide (ii) high levels of oxidative markers, such as 4-hydroxy-2-nonenal Michael-adducts and 3-nitro-tyrosine and (iii) altered p53 conformation, mainly due to nitration of its tyrosine residues. The consequences of high-unfolded p53 expression resulted in loss of p53 pro-apoptotic activity, and reduction of growth-associated protein 43 (GAP-43) mRNA and protein levels. The role of unfolded p53 in cell death resistance and lack of GAP-43 transcription was demonstrated by ZnCl 2 treatment. Zinc supplementation reverted p53 wild-type tertiary structure, increased cells sensitivity to acute cytotoxic injury and GAP-43 levels in SY5Y-APP clone.