mRNA expression profiling in cotyledons reveals significant up‐regulation of the two bovine pregnancy‐associated glycoprotein genes boPAG‐8 and boPAG‐11 in early gestation

The multigene family of pregnancy‐associated glycoproteins (PAGs) belongs to a group of aspartic proteases that are exclusively expressed by trophoblast cells in the placenta of even‐toed ungulates. In Bovidae, 22 different PAG genes (boPAGs) with a wide range of temporal and spatial expression‐ and glycosylation patterns have been reported to date. In this study we describe the mRNA expression patterns using real‐time quantitative PCR (qPCR) for selected modern (boPAG‐1, ‐9, ‐21) and ancient bovine PAGs (boPAG‐2, ‐8, ‐10, ‐11, ‐12) in cotyledonary tissue. The highest mean expression was detected in boPAG‐8 and lowest in boPAG‐10 (P < 0.05). Furthermore, boPAG‐8 and ‐11 were significantly greater expressed in early gestation compared with later pregnancy stages. The characterization of boPAG mRNA‐expression levels gives important insights for further protein analyses which will be valuable information for the development of new pregnancy detection systems.