title: Sexually Dimorphic Gene Expression in Bovine Conceptuses at the Initiation of Implantation.
abstract: In cattle, maternal recognition of pregnancy occurs on Day 16 via secretion of interferon tau (IFNT) by the conceptus. The endometrium can distinguish between embryos with different developmental competencies. In eutherian mammals, X-chromosome inactivation (XCI) is required to ensure an equal transcriptional level of most X-linked genes for both male and female embryos in adult tissues, but this process is markedly different in cattle than mice. We examined how sexual dimorphism affected conceptus transcript abundance and amino acid composition as well as the endometrial transcriptome during the peri-implantation period of pregnancy. Of the 5132 genes that were differentially expressed on Day 19 in male compared to female conceptuses, 2.7% were located on the X chromosome. Concentrations of specific amino acids were higher in the uterine luminal fluid of male compared to female conceptuses, while female conceptuses had higher transcript abundance of specific amino acid transporters (SLC6A19 and SLC1A35). Of note, the endometrial transcriptome was not different in cattle gestating a male or a female conceptus. These data support the hypothesis that, far from being a blastocyst-specific phenomenon, XCI is incomplete before and during implantation in cattle. Despite differences in transcript abundance and amino acid utilization in male versus female conceptuses, the sex of the conceptus itself does not elicit a different transcriptomic response in the endometrium.
authors.affiliation: School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, Ireland n.forde@leeds.ac.uk.
authors.forename: Niamh
authors.initials: N
authors.lastname: Forde
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: Veronica
authors.initials: V
authors.lastname: Maillo
authors.affiliation: School of Biomolecular and Biomedical Sciences, University College Dublin, Belfield, Dublin, Ireland.
authors.forename: Peadar
authors.initials: P
authors.lastname: O'Gaora
authors.affiliation: Center for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, United Kingdom.
authors.forename: Constantine A
authors.initials: CA
authors.lastname: Simintiras
authors.affiliation: Center for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, United Kingdom.
authors.forename: Roger G
authors.initials: RG
authors.lastname: Sturmey
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia.
authors.forename: Alan D
authors.initials: AD
authors.lastname: Ealy
authors.affiliation: Division of Animal Sciences, University of Missouri, Columbia, Missouri.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Spencer
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Gutierrez-Adan
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Rizos
authors.affiliation: School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, Ireland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Lonergan
mesh_terms: D026905:Amino Acid Transport Systems / Q000235:genetics; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001755:Blastocyst / Q000378:metabolism; D002417:Cattle / Q000196:embryology / Q000235:genetics* / Q000502:physiology; D010064:Embryo Implantation / Q000235:genetics* / Q000502:physiology; D004717:Endometrium / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D063990:Gene Ontology; D008297:Male; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000235:genetics* / Q000502:physiology; D012727:Sex Characteristics; D059467:Transcriptome; D014960:X Chromosome / Q000235:genetics; D049951:X Chromosome Inactivation / Q000235:genetics
chemical_list: D026905:Amino Acid Transport Systems; D000596:Amino Acids
keywords: XCI; amino acids; endometrium; gene expression; uterine luminal fluid