Methylmercury-Mediated Down-Regulation of mtHSP70 and Phospholipase A2 mRNA Expression in Human Neuroblastoma NB-1 Cells Identified by cDNA Macroarray Analysis.

Abstract

bCREST, Methylmercury (MeHg) is a well-known environmental pollutant that causes severe neurological damage, especially in the developing nervous system. When human neuroblastoma NB-1 cells were treated with MeHg at sublethal concentrations, down-regulation of two apoptosis-associated genes, mtHSP70 (GRP75/ PBP74/ mtHSP75 /HSPA9B/mortalin) and phospholipase A2 (PLA2), was identified using the cDNA macroarray technique. These observations were further confirmed by RT-PCR and Northern blotting experiments. Northern blotting data also demonstrated that only groups III and VI B of PLA2 were downregulated, while group IIE remained unchanged. These results suggest that the mtHSP70 and PLA2 may be involved in the MeHg-mediated degeneration of neuronal cells.