FIG 3.

c-Fos stability is enhanced during KSHV lytic replication. (A) Bac16-harboring 293T cells were induced with 20 ng/ml TPA and 0.3 mM NaB for 48 h, followed by an additional 4 h of incubation with either 20 μg/ml MG132 or 20 μg/ml cycloheximide (CHX). (B) BCBL1 cells were induced with either 20 ng/ml TPA or 1 mM NaB for 48 h, and then 20 μg/ml MG132 was added, followed by an additional 4 h of incubation. The cells were collected and lysed, and c-Fos and c-Jun were analyzed as indicated. (C) Both 293T cells and Bac16-harboring 293T cells were treated with 3 mM NaB for 3 days, after which the half-life of c-Fos was measured under each condition, following the addition of 40 μg/ml CHX and an additional incubation for the indicated length of time. Whole-cell extracts were analyzed with anti-c-Fos and anti-tubulin antibodies, and quantitation of c-Fos band intensity was analyzed using NIH ImageJ software and is shown as the mean values from duplicate experiments.