Fig. 4

rab27 silencing impacts Anaplasma phagocytophilum acquisition during blood feeding of Ixodes scapularis nymphs. A C57BL/6 mice were intraperitoneally (i.p.) injected with 10⁷ A. phagocytophilum (Ap) 7 days prior to tick placement. Ticks were microinjected with small interfering (si-rab27) (green) or scrambled (sc-rab27)(gray) RNA, incubated for 24 h, and then placed on infected mice. Ticks were recovered daily from a water trap. Remaining ticks attached to the mouse at day 3 were removed by forceps. B rab27 silencing in I. scapularis ticks placed on Ap infected mice. The graph represents three independent experiments combined. si-rab27 (n = 9). sc-rab27 (n = 35). Mean ± standard deviation (SD) is plotted. Statistical significance was evaluated by an unpaired, two-tailed t-test with Welch’s correction. ***P < 0.0005. C Impact of rab27 silencing on tick attachment. The graph represents three independent experiments combined. Fisher’s exact test was performed to determine statistical differences. ****P < 0.0001. D Effect of rab27 silencing on tick weight. The graph represents three independent experiments combined. si-rab27 (n = 11). sc-rab27 (n = 37). Statistical significance was evaluated by an unpaired, two-tailed t-test with Welch’s correction. *P < 0.05. Ticks recorded as a weight of 0 mg were below the limit of detection of our scale (1 mg). E Impact of rab27 silencing on Ap acquisition. The graph represents three independent experiments combined. si-rab27 (n = 10). sc-rab27 (n = 32). Mean ± SD is plotted. Statistical significance was evaluated by an unpaired, two-tailed t-test with Welch’s correction. ****P < 0.0001