Glyceraldehyde-3-phospate dehydrogenase is translocated into nuclei through Golgi apparatus during apoptosis induced by 6-hydroxydopamine in human dopaminergic SH-SY5Y cells

Abstract

6-Hydroxydopamine is a neurotoxin specific to dopamine neurons, and this neurotoxin at 20 μM was confirmed to induce mainly apoptosis in human dopaminergic neuroblastoma SH-SY5Y cells. During the apoptotic process, translocation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) into nuclei was observed, which is now proposed as an apoptogenic signal in various types of apoptosis. However, it remains to be clarified, how GAPDH is translocated into nuclei. In this paper, GAPDH translocation was followed by fluoro- and electron-microscopic observation using antibody against GAPDH. Before the nuclear translocation, a condensed mass of GAPDH protein was detected in the Golgi apparatus, which was identified by 6-{[ N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]hexanoyl}-sphingosine, a selective marker of Golgi apparatus. These results suggest that the Golgi apparatus may be involved in the compartmentalization of GAPDH from cytosol to nuclei.