title: WINGLESS (WNT) signaling is a progesterone target for rat uterine stromal cell proliferation.
abstract: Preparation of mammalian uterus for embryo implantation requires a precise sequence of cell proliferation. In rodent uterus, estradiol stimulates proliferation of epithelial cells. Progesterone operates as a molecular switch and redirects proliferation to the stroma by down-regulating glycogen synthase kinase-3β (GSK-3β) and stimulating β-catenin accumulation in the periluminal stromal cells. In this study, the WNT signal involved in the progesterone-dependent proliferative switch was investigated. Transcripts of four candidate Wnt genes were measured in the uteri from ovariectomized (OVX) rats, progesterone-pretreated (3 days of progesterone, 2mg/daily) rats, and progesterone-pretreated rats given a single dose (0.2µg) of estradiol. The spatial distribution of the WNT proteins was determined in the uteri after the same treatments. Wnt5a increased in response to progesterone and the protein emerged in the periluminal stromal cells of progesterone-pretreated rat uteri. To investigate whether WNT5A was required for proliferation, uterine stromal cell lines were stimulated with progesterone (1µM) and fibroblast growth factor (FGF, 50ng/mL). Proliferating stromal cells expressed a two-fold increase in WNT5A protein at 12h post stimulation. Stimulated stromal cells were cultured with actinomycin D (25µg/mL) to inhibit new RNA synthesis. Relative Wnt5a expression increased at 4 and 6 h of culture, suggesting that progesterone plus FGF preferentially increased Wnt5a mRNA stability. Knockdown of Wnt5a in uterine stromal cell lines inhibited stromal cell proliferation and decreased Wnt5a mRNA. The results indicate that progesterone initiates and synchronizes uterine stromal cell proliferation by increasing WNT5A expression and signaling.
authors.affiliation: Department of BiologyPittsburg State University, Pittsburg, Kansas, USA vrider@pittstate.edu.
authors.forename: Virginia
authors.initials: V
authors.lastname: Rider
authors.affiliation: Department of BiologyPittsburg State University, Pittsburg, Kansas, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Talbott
authors.affiliation: Department of BiologyPittsburg State University, Pittsburg, Kansas, USA.
authors.forename: Anuradha
authors.initials: A
authors.lastname: Bhusri
authors.affiliation: Department of BiologyPittsburg State University, Pittsburg, Kansas, USA.
authors.forename: Zach
authors.initials: Z
authors.lastname: Krumsick
authors.affiliation: Department of BiologyPittsburg State University, Pittsburg, Kansas, USA.
authors.forename: Sierra
authors.initials: S
authors.lastname: Foster
authors.affiliation: Department of BiologyPittsburg State University, Pittsburg, Kansas, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Wormington
authors.affiliation: Department of Radiation OncologyThe University of Kansas Medical Center, Kansas City, Kansas, USA.
authors.forename: Bruce F
authors.initials: BF
authors.lastname: Kimler
mesh_terms: D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D055785:Gene Knockdown Techniques; D011374:Progesterone / Q000378:metabolism* / Q000494:pharmacology; D020871:RNA Stability; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D014599:Uterus / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D060449:Wnt Signaling Pathway / Q000235:genetics; D000071818:Wnt-5a Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D000071818:Wnt-5a Protein; C491837:Wnt5a protein, rat; D011374:Progesterone
keywords: Wnt signaling; cell proliferation; progesterone; uterus