Alpha-synuclein /A53T mutant damages the mitochondria associated membrane and results in mitochondrial structural abnormalities and autophagy of neuroblastoma cell line SH-SY5Y

Abstract

Objective To investigate the effect of α-synuclein (α-syn) A53T mutant on mitochondria associated membrane (MAM) of endoplasmic reticulum, and to explore the molecular and cellular mechanism of neuronal toxicity induced by α-syn mutation. Methods Human neuroblastoma cell line SH-SY5Y with over expressed α-syn/A53T mutation gene, was constructed. MAM was labeled by proximity ligation assay and the number of MAM was counted. Mitochondrial calcium ions were labeled with Rhod2 and the changes of mitochondrial calcium ions were dynamically observed. The structure of mitochondria was further observed by laser confocal microscopy and electron microscopy. Results Over-expression of α-syn/A53T mutants resulted in significant cytotoxicity, inhibition of MAM calcium transport, and short rod-shaped and globular mitochondria as found by confocal laser microscopy. Mitochondrial vacuoles and autophagy were observed by electron microscopy. Conclusions α -syn/A53T mutants can cause mitochondrial structural abnormalities and autophagy by destroying MAM.

Keywords

• α-synuclein|mitochondria associated membrane of endoplasmic reticulum|mitochondria|parkinson's disease