Fig. 1.

Pulse–chase metabolic labeling of pro-NT-3 in primary cultures of hippocampal neurons (A) and AtT-20 cells (B). Cells were infected with VV encoding the NT-3 precursor for 1 hr and postincubated in fresh medium without virus for 8 hr. Cells were then exposed to medium containing [³⁵S] Cys-Met for 30 min and chased for 0, 0.5, 1, 2, 4, and 8 hr. Identical volumes (750 μl) of cell lysates (CL) and conditioned media (CM) were incubated with antibodies to NGF, which immunoprecipitate NT-3, and electrophoresed on 13–22% SDS gradient gels.