Fig. 1

Dnmt1 is required for reproduction in O. fasciatus. a Assessment of RNAi treatment targeting Dnmt1 using qRT-PCR demonstrates successful reduction in transcription in ovaries compared to control. Dots indicate mean expression level, and error bars indicate standard error of the mean. b Parental RNAi injection with ds-dnmt1-1 significantly affected the development of eggs laid by injected females compared to eggs laid by control females. Dots indicate mean number of eggs developed, and error bars indicate standard error of the mean. c Whole ovaries from females removed 12–14 days post-injection (i and iv). In control females (i), mature oocytes can be seen collecting in the lateral oviduct (Od). In ds-dnmt1-1 females (iv), no mature oocytes are apparent, but the oviduct has filled with a yolk-like substance. Follicular epithelium surrounding a maturing oocyte at 20- (ii and v) and 40-times (iii and vi) magnification. Nuclei are stained with Hoechst 33258. Nuclei from control follicular epithelium (ii and iii) are round and regular in shape. Nuclei from ds-dnmt1-1 females (v and vi) are highly irregular in shape