Figure 2.

Induction of early response genes. Cells were cultured for 3 days in the presence (1 μg/ml) and absence of tetracycline in RPMI containing 10% FBS and were stimulated with cognate ligands at a concentration of 100 ng/ml. Profiles of the early response genes induced by NGF and BDNF are similar. The response was more sustained in the absence of tetracycline. Fifteen micrograms of total RNA was electrophoresed in 1.2% formaldehyde gel and subsequently transferred to nitrocellulose membrane. tet +: 1 μg tetracycline/ml; tet −: 0 μg tetracycline/ml.