Stimulation of a rat uterine stromal cell line in culture reveals a molecular switch for endocrine-dependent differentiation.
Differentiation of uterine stromal cells is critical for the establishment of pregnancy. This study had two purposes: (i) to validate the use of the UIII rat uterine stromal cell model for investigating mechanisms underlying decidual cell differentiation, and (ii) to use this cell model to identify a molecular switch for cellular entry into the decidual cell differentiation pathway. Quiescent rat uterine stromal cells were transfected with a 500 bp segment of the decidual prolactin-related protein (dPRP) promoter ligated to a luciferase reporter gene. Cells were incubated in low-serum medium, or in low-serum medium containing progesterone (1 microM), estradiol 17-beta (10 nM), cholera toxin (10 ng/ml) and interleukin-11 (10 ng/ml). Protein extracts were collected 48 h later and luciferase was measured in the cellular lysates. Cholera toxin and interleukin-11 stimulated luciferase expression (P< 0.05) and addition of sex steroids further increased (P< 0.05) dPRP promoter activity. Stromal cells did not proliferate (P< 0.05) under differentiation conditions. Deletion analysis of the dPRP promoter revealed maximal luciferase expression between -250 and -500 bp relative to the transcription start site. Comparison of cyclin E/Cdk2 activity between proliferating and differentiating cells showed a 3-fold increase (P< 0.05) at 12 h in differentiating cells. The results suggest that cyclin E/Cdk2 serves as a molecular switch for uterine stromal cell entry into the decidual cell differentiation pathway.
Rider
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Department of Biology, Pittsburg State University, Pittsburg, Kansas 66762, USA. VRider@pittstate.edu
Potapova
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Dai
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Soares
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MJ
D000818:Animals; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D002772:Cholera Toxin / Q000494:pharmacology; D019927:Cyclin E / Q000235:genetics / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005812:Genes, Switch; D017370:Interleukin-11 / Q000494:pharmacology; D008156:Luciferases / Q000032:analysis / Q000235:genetics; D011374:Progesterone / Q000494:pharmacology; D011388:Prolactin / Q000031:analogs & derivatives* / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D051381:Rats; D013268:Stimulation, Chemical; D017154:Stromal Cells / Q000166:cytology* / Q000378:metabolism; D014162:Transfection / Q000379:methods; D014599:Uterus / Q000166:cytology* / Q000378:metabolism
D019927:Cyclin E; D017370:Interleukin-11; C079559:Prl8a2 protein, rat; D011374:Progesterone; D004958:Estradiol; D011388:Prolactin; D002772:Cholera Toxin; D008156:Luciferases