Figure 4.

MosIR has no effect on transcriptional silencing of cognate sequences. (A) A schematic composition of the MosP reporter transgene. (B) EGFP signal in MosP-positive and WT newborn and adult mice. (C) EGFP fluorescence in tails of mice carrying MosP and MosIR transgenes is not reduced. Bright signal in some MosP-positive tails (e.g. first on the left in the top row) is caused by the lack of pigmentation of the tails. The MosP tail on the left in the lower row belongs to an F1 animal where we observed a spontaneous transcriptional silencing accompanied by DNA methylation of the MosP promoter (Supplementary Figure S4). All images were obtained using the same settings. (D) EGFP signal in tail, kidney, brain and oocytes of MosP, MosIR and MosP & MosIR mice. Organs were collected from siblings of one litter and their images were taken with the same camera settings.