FIG. 2.

Inhibition of KSHV Rta-induced late-gene expression by PAA. (A) HH-B2 cells were untreated (lanes 1 and 6), exposed to chemical inducing stimuli (lanes 2, 3, 7, and 8), or transfected with a KSHV ORF50 expression plasmid, gRta (lanes 4 and 9), or gRta mutant plasmids (lane 5 and 10). One-half of the cultures were exposed to 500 μM PAA at time zero immediately after electroporation (lanes 6 to 10). RNA harvested 30 h after transfection was analyzed by Northern blotting with probes for KSHV ORF65 (top) and K8 and K8.1 (bottom). RNaseP was used to control for RNA loading. (B) HH-B2 cells were transfected with vector pRTS or with vector containing ORF50/Rta from the BC-1 strain, in the presence or absence of PAA. Cell extracts prepared 48 h after transfection were analyzed by immunoblotting with antibodies to ORF65.