Temporal increase of two proteins in PC-12 pheochromocytoma cells induced by nerve growth factor

Two-dimensional gel electrophoresis revealed two protein spots, a (molecular weight 70,000, pI 4.6) and b (molecular weight 69,000, pI 4.4) in PC-12 cells (rat pheochromocytoma cells). When the cells were induced to differentiate with nerve growth factor, the amount of protein in spot a, and later spot b increased with time, then the amount in both spots gradually decrease to undetectable level. These spots were not detected in adult rat brain nor in other cell lines of rat and mouse. Thus, these proteins can be used as markers to follow the differentiation of PC-12 cells.