Characterization of the placental transcriptome through mid to late gestation in the mare

Autoři: Shavahn C. Loux aff001;  Pouya Dini aff001;  Hossam El-Sheikh Ali aff001;  Theodore Kalbfleisch aff001;  Barry A. Ball aff001
Působiště autorů: Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, United States of America aff001;  Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium aff002;  Theriogenology Department, Faculty of Veterinary Medicine, University of Mansoura, Mansoura City, Egypt aff003
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224497


The placenta is a dynamic organ which undergoes extensive remodeling throughout pregnancy to support, protect and nourish the developing fetus. Despite the importance of the placenta, very little is known about its gene expression beyond very early pregnancy and post-partum. Therefore, we utilized RNA-sequencing to characterize the transcriptome from the fetal (chorioallantois) and maternal (endometrium) components of the placenta from mares throughout gestation (4, 6, 10, 11 m). Within the endometrium, 47% of genes changed throughout pregnancy, while in the chorioallantois, 29% of genes underwent significant changes in expression. Further bioinformatic analyses of both differentially expressed genes and highly expressed genes help reveal similarities and differences between tissues. Overall, the tissues were more similar than different, with ~ 95% of genes expressed in both tissues, and high similarities between the most highly expressed genes (9/20 conserved), as well as marked similarities between the PANTHER pathways identified. The most highly expressed genes fell under a few broad categories, including endocrine and immune-related transcripts, iron-binding proteins, extracellular matrix proteins, transport proteins and antioxidants. Serine protease inhibitors were particularly abundant, including SERPINA3, 6 and 14, as well as SPINK7 and 9. This paper also demonstrates the ability to effectively separate maternal and fetal components of the placenta, with only a minimal amount of chorioallantoic contamination in the endometrium (~8%). This aspect of equine placentation is a boon for better understanding gestational physiology and allows the horse to be used in areas where a separation of fetal and maternal tissues is essential. Overall, these data represent the first large-scale characterization of placental gene expression in any species and include time points from multiple mid- to late-gestational stages, helping further our understanding of gestational physiology.

Klíčová slova:

Extracellular matrix proteins – Gene expression – Horses – Immune response – Immune system proteins – placenta – Pregnancy – endometrium


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