Validation of the microarray results and comparison with Q-PCR. (A) RNA from the microarray experiments depicted in panel A were tested for up- or down-regulation of specific genes using Q-PCR. Q-PCR data are represented with solid bars, whereas values from microarray experiments are depicted as striped bars. Both data sets are presented as mean ± SEM from three individual experiments. (B) Correlation analysis of the microarray and Q-PCR transcript measurements for nine select F. tularensis LVS ORFs. The microarray log2 values were plotted against the Q-PCR log2 data. The correlation coefficient (R2) between the two analyses is 0.94.