Fig. 10

Varying mCherry signal intensity in EnOWP6-mCherry oocysts and excystation. a and b show two oocysts in the same visual field and 10s exposure signal in the red mCherry channel. A shows strong mCherry signal and YFP expression in all four sporocysts. b: shows no mCherry expression and YFP expression in two sporocysts. c and d: Images from a and b after image processing (intensity, saturation). The signals from A are clearly overregulated (c) but hidden signal in b became visible in d. The EnOWP6_mCherry was detected in nearly all investigated oocysts (see also Table 1) and always in four sporocyst per oocyst whereas the YFP signals altered. E-L: Excystation of sporocysts and sporozoites from EnOWP6-mCherry oocysts. E-H: Free sporocyst. The mCherry signals clearly margin the sporocyst and surround the green fluorescent signal of the sporozoites. I-K: Recently, excysted sporozoites (green) next to its abandoned sporocyst with non fluorescent material inside and a red fluorescent sporocyst wall. A-D: Overlay of mCherry and YFP fluorescence, Scale bar 10 μm. E and I: mCherry; F and J: YFP; G and K: overlay of mCherry an YFP; H and L: overlay of mCherry, YFP, and bright field images. E-H: Scale bar 5 μm; I-L: Scale bar 10 μm