title: Eph-ephrin A system regulates murine blastocyst attachment and spreading.
abstract: Although numerous adhesion molecules are expressed on mammalian endometrial epithelial cells, there have not been any studies of a mechanism to prevent premature attachment of the embryo. In this study, we examined the possible involvement of Eph-ephrin interaction, which can induce repulsive forces. In mice, Eph A1, A2, and A4 were expressed on endometrial epithelial cells and ephrin A1-4 on blastocysts. Reverse transcriptase-polymerase chain reaction showed that mRNA expression of ephrin A1-4 on embryos transiently decreased around the implantation period. Immunohistochemistry demonstrated that the expression of Eph A1 on endometrial epithelial cells and ephrin A1 and A3 expression on embryos decreased at implantation sites. Recombinant Eph A1 reacted with cell the surface of ephrin A-bearing trophectoderm cells. Attachment assays using Eph A1-coated dishes showed that blastocyst attachment was reversibly inhibited by Eph A1. These findings suggest an important role of the Eph-ephrin A system in regulating the initial embryo-maternal contact during the cross-talk period that precedes embryo implantation.
authors.affiliation: Department of Gynecology and Obstetrics, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto, Japan.
authors.forename: Haruko
authors.initials: H
authors.lastname: Fujii
authors.forename: Keiji
authors.initials: K
authors.lastname: Tatsumi
authors.forename: Kenzo
authors.initials: K
authors.lastname: Kosaka
authors.forename: Shinya
authors.initials: S
authors.lastname: Yoshioka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fujiwara
authors.forename: Shingo
authors.initials: S
authors.lastname: Fujii
mesh_terms: D000818:Animals; D001483:Base Sequence; D001755:Blastocyst / Q000166:cytology* / Q000502:physiology*; D002448:Cell Adhesion / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D017931:DNA Primers / Q000235:genetics; D010064:Embryo Implantation / Q000235:genetics / Q000502:physiology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D011247:Pregnancy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D036081:Receptors, Eph Family / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D036081:Receptors, Eph Family