Placenta-restricted gene expression in <i>Tpbpa</i>r/<i>Ada</i>f-<i>Ada</i>P-<i>Cre</i> transgenic mice.

<p>Pregnant mice were sacrificed on gestation day 16.5 and placentas, multiple organs and embryos were collected. (<b>A</b>) Copy number of transgenes was determined by qPCR analysis in <i>Tpbpa</i>r/<i>Ada</i>f-<i>Ada</i>P-<i>Cre</i> transgenic founders. Genotyping analysis (<b>B</b>, <b>D</b>) of <i>Tpbpa</i>r/<i>Ada</i>f-<i>Ada</i>P-<i>Cre</i> transgenes by PCR and expression pattern of <i>Cre</i> mRNA (<b>C</b>, <b>E</b>) analyzed by RT-qPCR in placenta, fetus and multiple maternal organs from female transgenic mice (derived from Tg 5 founder) mated with wild type FVB male mice. β-actin was used as an internal control. Tg placental RNA is used as positive control. nd, not detectable; P, Positive control; N, Negative control. (<b>F</b>) Immunochemistry staining of Cre recombinase using anti-Cre antibody in the placentas of pregnant <i>Tpbpa</i>r<i>/Ada</i>f<i>-Ada</i>P<i>-Cre</i> females mated with wild type FVB males. Placentas with <i>Tpbpa</i>r<i>/Ada</i>f-<i>Ada</i>P-<i>Cre</i> transgenes (Cr⁺(Tg)) expressed Cre protein in giant cells (indicated by long arrow), spongiotrophoblast cells (indicated by short arrow) and cells in the labyrinthine zone (indiated by arrow head)of placentas, with highest expression in the spongiotrophoblast zone. Panel <b>F</b> (inset) showed nuclear localization of Cre in trophoblast cells. Placentas lacking <i>Tpbpa</i>r/<i>Ada</i>f-<i>Ada</i>P-Cre transgenes (Cre⁻, panel <b>F</b>) and multiple organs from pregnant transgenic dams (<b>G</b>) showed no Cre immunostaining. Endogenous ADA immunostaining was performed in placentas with or without <i>Tpbpa</i>r/<i>Ada</i>f-<i>Ada</i>P-Cre transgenes using anti-ADA antibody (panel <b>F</b>). Scale bar, 100 µm (placenta) or 50 µm (inset) and 500 µm for maternal organs.