title: Down-regulation of interferon tau gene transcription with a transcription factor, EOMES.
abstract: Interferon tau (IFNT), produced for a short interval during early pregnancy by the ruminant embryonic trophectoderm, is essential for the maintenance of early pregnancy, but the mechanism by which it is transcriptionally regulated has not been fully determined. To identify a transcription factor(s) involved in the down-regulation of IFNT genes, mRNAs for various known transcription factors were investigated by reverse-transcriptase and real-time PCR in conceptus tissues collected on Days 15, 17, and 21, or Days 17, 20, and 22 of ovine or bovine pregnancy, respectively. In particular, the T-box protein eomesodermin (EOMES) exhibited high mRNA expression in Day 17 or 22 ovine or bovine conceptuses. Interaction between EOMES and the identified transcription factors was studied using transient transfection, revealing that ovine/bovine IFNT-reporter transactivation was down-regulated by EOMES. Transcription factor interactions with EOMES were further studied through immunoprecipitation, demonstrating an association between EOMES and cAMP-response element binding protein (CREB)-binding protein (CREBBP). Uterine flushing media collected from cyclic or early pregnancy animals were added to bovine trophoblast CT-1 cells cultured on type-I collagen (monoculture) or bovine uterine epithelial cells (coculture) in an attempt to regulate EOMES expression. In the coculture, but not the monoculture, addition of uterine flushing from Day 17 pregnant animals resulted in increased EOMES expression in CT-1 cells. These results suggest that as conceptuses attach to the uterine epithelium, IFNT gene transcription is down-regulated by an increase in EOMES expression and EOMES-CREBBP binding in the attached trophoblast cells.
authors.affiliation: Laboratory of Animal Breeding and Reproduction, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan. asaku@mail.ecc.u-tokyo.ac.jp
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Sakurai
authors.forename: Hanako
authors.initials: H
authors.lastname: Bai
authors.forename: Rulan
authors.initials: R
authors.lastname: Bai
authors.forename: Daisuke
authors.initials: D
authors.lastname: Sato
authors.forename: Miki
authors.initials: M
authors.lastname: Arai
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Okuda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ideta
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Aoyagi
authors.forename: James D
authors.initials: JD
authors.lastname: Godkin
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Imakawa
mesh_terms: D000818:Animals; D050882:CREB-Binding Protein / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D015536:Down-Regulation / Q000502:physiology*; D010064:Embryo Implantation / Q000502:physiology*; D005260:Female; D007370:Interferon Type I / Q000096:biosynthesis*; D011247:Pregnancy / Q000378:metabolism*; D011257:Pregnancy Proteins / Q000096:biosynthesis*; D012756:Sheep; D020825:T-Box Domain Proteins / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology; D014327:Trophoblasts / Q000166:cytology / Q000378:metabolism*
chemical_list: D007370:Interferon Type I; D011257:Pregnancy Proteins; D020825:T-Box Domain Proteins; C020947:interferon tau; D050882:CREB-Binding Protein