Modifications of tau protein during neuronal cell death

Article type: Research Article

Authors: Lorío, Gretchen | Avila, Jesús | Díaz-Nido, Javier^{; *}

Affiliations: Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Universidad Autónoma de Madrid, 28049 Madrid, Spain

Correspondence: [*] Corresponding author: Javier Díaz-Nido, Departamento de Biología Molecular, Universidad Autónoma de Madrid, Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), 28049 Madrid, Spain. Tel.: +34 91 397 8710; Fax: +34 91 397 4799; E-mail: javier.diaznido@cbm.uam.es.

Abstract: Accumulation of hyperphosphorylated tau protein and progressive neuronal loss are among the major hallmarks of certain neurodegenerative disorders including Alzheimer's disease. However, the relationship between tau phosphorylation and neuronal cell death remains unclear. Here we have analyzed tau modifications during two forms of neuronal death, apoptosis and necrosis, using primary cultures of cerebellar granule neurons as a simple model system. Induction of neuronal apoptosis by inhibition of phosphatidylinositol 3-kinase results in a rapid increase in the phosphorylation of tau, which is followed by the dephosphorylation and cleavage of the protein. In contrast, necrosis triggered by high salt shock or glutamate treatment leads to a rapid dephosphorylation and an almost complete proteolysis of tau. These data suggests that a transient tau hyperphosphorylation occurs at an early stage of apoptosis, whereas tau is dephosphorylated and cleaved during the late phase of apoptosis as well as in necrotic neurons.

DOI: 10.3233/JAD-2001-3607

Journal: Journal of Alzheimer's Disease, vol. 3, no. 6, pp. 563-575, 2001