ALTERATIONS OF CYTOSKELETAL TAU-PROTEIN OF SH-SY5Y HUMAN NEUROBLASTOMA-CELLS AFTER EXPOSURE TO MPTP

In this study, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 10( -3) to 10(-4) M for 2 to 5 days) increased the expression of microtubu le-associated tau protein in both the supernatant and pellet fractions of lysed SH-SY5Y human neuroblastoma cells. The western blot using an ti-tau-1 antibodies demonstrated that the cells contained at least six isoforms of tau proteins, five with molecular weights from 45 to 62 k D. Reverse transcriptase polymerase chain reaction (RT-PCR) using prim ers coding whole length tau protein further confirmed the presence of tau in SH-SY5Y cells. The PCR product of tau in SH-SY5Y cells had appr oximately 1050 base pairs. MPTP caused an increased expression of the PCR product of tau, suggesting that the toxicant caused an increase in mRNA coding the tau protein. The expression of cytoskeletal tau prote in may, therefore, provide a marker for MPTP neurotoxicity in SH-SY5Y cells. (C) 1998 Intox Press, Inc.