Rac1 is induced in the uterus during early pregnancy.

<p><b>(A)</b> Induction of <i>Rac1</i> mRNA in the uterus during experimentally-induced decidualization. Uterine RNA was purified from mice at different times after decidual stimulation and analyzed by qPCR. Relative levels of <i>Rac1</i> mRNA expression in uteri after decidual stimulation are compared to those in unstimulated control uteri. Data represent mean ± SEM from three separate samples and were analyzed by one-way ANOVA with Bonferroni post-test. Letters indicate statistically significant differences (<i>P</i> < 0.0001). <b>(B)</b> Expression of <i>Rac1</i> during early pregnancy overlaps with the decidual phase of gestation. qPCR was performed to monitor the expression of <i>Rac1</i> mRNA in uteri on days 1 to 8 of gestation. The relative levels of gene expression on different days of pregnancy were determined by setting the expression level of <i>Rac1</i> mRNA on day 1 of pregnancy at 1.0. <i>Rplp0</i>, encoding a ribosomal protein, was used to normalize the level of RNA. Data represent mean ± SEM from three separate samples and were analyzed by one-way ANOVA with Bonferroni post-test. Letters indicate statistically significant differences (<i>P</i> < 0.0001). <b>(C)</b> Localization of active RAC1 protein in uterine stromal cells during early pregnancy. Uterine sections on day 7 of pregnancy were subjected to immunofluorescence (IF) histochemistry using anti-RAC1-GTP antibody. Panels a, b, and c show immunostaining of RAC1-GTP; panels d, e, and f show staining with non-immune IgG. AMD, MD and E indicate antimesometrial decidua, mesometrial decidua and embryo, respectively.