Steady-state polypeptide modulations associated with nerve growth factor (NGF)-induced terminal differentiation and NGF deprivation-induced apoptosis in human neuroblastoma cells.

摘要: Human neuroblastoma SH-SY5Y cells differentiate terminally in culture upon exposure to nerve growth factor (NGF) for 4-5 weeks. The neuronal phenotypic properties acquired response prolonged NGF treatment include morphological differentiation, cessation of mitotic activity, marker expression, increased membrane electrical potentials, and a survival dependence trophic support (Jensen, L.M. (1987) Dev. Biol. 120, 56-64). Thus, differentiated cultures survive indefinitely the continued presence NGF, however, withdrawal from effects loss cellular viability within 3-6 days. Here, we show that death caused by deprivation is characteristic apoptosis. To compare differentiation promoting neurotrophic whole cell extracts were analyzed two-dimensional polyacrylamide gel electrophoresis using isoelectric focusing nonequilibrium pH gradient gels first dimension. Steady-state levels polypeptides extracted whole-cell lysates naive (untreated) cells, NGF-deprived compared. Over 1,000 spots each computer-aided spot matching densitometry. We noted 25 decreased during including 15 10 or more. five induced very low undetectable cells. Withdrawal produced alterations steady-state protein patterns substantially distinct those occurring differentiation. While most proteins do not appear affected early after withdrawal, others rapidly return comparable with state some changes are enhanced further withdrawal. Three regulated uniquely two induced, on average, 20- 28-fold another was depressed more than 7-fold deprivation, before death. These data indicate elicits both constitutive nonconstitutive gene expression suggest correlate regulation different products.