FIG. 1.

Effect of PKC inhibitors on R. rickettsii-induced NF-κB activation. Cultured endothelial cells were incubated with BM-1 or calphostin C (CC) for 1 h prior to and during a 3-h infection with R. rickettsii. Nuclear extracts were prepared, and activation of NF-κB was measured by gel shift analysis by using a ³²P-labeled oligonucleotide containing a consensus NF-κB binding sequence. A 10-fold molar excess of unlabeled oligonucleotide was added (+ cold) to demonstrate specificity of complex formation. Autoradiographic exposures were typically for 18 to 24 h. The positions of gel-shifted NF-κB complexes and free probe are indicated. NS represents a nonspecific and noninducible complex.