title: Expression of steroidogenic proteins in bovine placenta during the first half of gestation.
abstract: The aim of the present study was to determine the occurrence and localisation of the principal steroidogenic proteins in bovine placenta from Day 50 to Day 120 of pregnancy. Immunohistochemistry revealed that, at all stages investigated, bovine steroidogenic acute regulatory protein (StAR), cytochrome P45011A1 and hydroxy-δ-5-steroid dehydrogenase, 3β- and steroid δ-isomerase 1 proteins were found principally at the fetomaternal interdigitations: the chorionic villus and maternal septum. Moreover, caruncular epithelial cells and uninucleate trophoblast cells were the principal cells detected that were positive for the three markers. Western blot analysis showed that only caruncular tissue expressed all three steroidogenic markers; in contrast, cotyledons only expressed StAR and cytochrome P45011A1. Immunoblot results showed a complementary pattern of StAR and cytochrome P45011A1 expression between caruncles and cotyledons at different stages. These observations suggest that, in early pregnancy, the maternal compartment contributes significantly to bovine placental steroidogenesis, particularly for the synthesis of progesterone. Furthermore, the variation in StAR and cytochrome P45011A1 expression between caruncular and cotyledonary tissues across gestation suggests that placental steroidogenesis requires cell-to-cell communication between maternal and fetal cells.
authors.affiliation: Centre de Recherche en Reproduction Animale, Faculté de Médecine Vétérinaire, Université de Montréal, 3200 Sicotte, Saint Hyacinthe, Québec, J2S 7C6, Canada.
authors.forename: Adriana
authors.initials: A
authors.lastname: Verduzco
authors.forename: Gilles
authors.initials: G
authors.lastname: Fecteau
authors.forename: Réjean
authors.initials: R
authors.lastname: Lefebvre
authors.forename: Lawrence C
authors.initials: LC
authors.lastname: Smith
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Murphy
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics* / Q000378:metabolism; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D015971:Gene Expression Regulation, Enzymologic; D005865:Gestational Age; D053858:Metabolic Networks and Pathways / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000235:genetics* / Q000378:metabolism; D011270:Pregnancy, Animal / Q000235:genetics / Q000378:metabolism; D011375:Progesterone Reductase / Q000235:genetics / Q000378:metabolism; D013256:Steroids / Q000096:biosynthesis*; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D010750:Phosphoproteins; D011257:Pregnancy Proteins; D013256:Steroids; D000098682:Steroidogenic Acute Regulatory Protein; D011375:Progesterone Reductase; D002786:Cholesterol Side-Chain Cleavage Enzyme