FIG. 3.
Expression of oppA mRNA transcripts under various environmental conditions. Total RNA was isolated from in vitro-grown organisms at 25°C and 37°C or from fed and unfed Ixodes ticks. cDNA to total RNA was generated using random hexamers. Expression of mRNA for each individual oppA was examined by quantitative real-time RT PCR. Expression levels of oppA-I (A), oppA-II (B), oppA-III (C), oppA-IV (D), and oppA-V (E and F) are shown relative to that of expression of the gene in in vitro-grown organisms at 25°C, which was assigned a relative value of 1.0. Data shown are averages from two to three experiments performed in duplicate. Error bars represent standard errors of the means. Statistical significance was calculated using the Kruskal-Wallis method. %, significant (P < 0.05) differences in expression level compared with samples grown at 25°C; #, significant differences in expression level compared with samples grown at 37°C; $, significant differences in gene expression level in fed ticks; X, significant differences in gene expression level in unfed ticks; &, significant differences from expression levels in mouse tissue. Note that the scale changes for each graph. Data for oppA-IV are split into two graphs (panels E and F) due to the wide range of relative expression.