Description
Purpose: Parturition is delayed by approximately 12 hours in transgenic mice expressing human corticotropin-releasing hormone (CRH) in placenta. The goal of the study was to identify the pathways in reproductive tissues (uterus and placenta) altered by placental expression of human CRH. Methods: Human BAC RP11-366K18 (CHORI) containing human CRH and cis-regulatory region was inserted into the mouse genome by microinjection and random integration to create the BAC1 line. The CRISPR/Cas9 system was used to delete a CRH regulatory element from the BAC1 line to create the CR1 line, eliminating expression of CRH in placenta. Total expression of uterus and placenta by RNA-seq at embryonic day 18.5 were compared between BAC1, CR1, and nontransgenic mice. Results: Genes known to be associated with luteolysis and initiation of parturition (Cav1, Gja1, Oxtr, Ptgs1, Ptgs2) were not differentially expressed in uterus of this model. Conclusions: CRH-mediated delay of parturition is likely independent of luteolysis. Overall design: mRNA-seq was performed on uterus and placenta harvested at embryonic day 18.5 from nontransgenic mice, Tg(BAC1) mice, and Tg(CR1) mice.