title: Estradiol differentially induces progesterone receptor isoforms expression through alternative promoter regulation in a mouse embryonic hypothalamic cell line.
abstract: Progesterone receptor (PR) presents two main isoforms (PR-A and PR-B) that are regulated by two specific promoters and transcribed from alternative transcriptional start sites. The molecular regulation of PR isoforms expression in embryonic hypothalamus is poorly understood. The aim of the present study was to assess estradiol regulation of PR isoforms in a mouse embryonic hypothalamic cell line (mHypoE-N42), as well as the transcriptional status of their promoters. MHypoE-N42 cells were treated with estradiol for 6 and 12 h. Then, Western blot, real-time quantitative reverse transcription polymerase chain reaction, and chromatin and DNA immunoprecipitation experiments were performed. PR-B expression was transiently induced by estradiol after 6 h of treatment in an estrogen receptor alpha (ERα)-dependent manner. This induction was associated with an increase in ERα phosphorylation (serine 118) and its recruitment to PR-B promoter. After 12 h of estradiol exposure, a downregulation of this PR isoform was associated with a decrease of specific protein 1, histone 3 lysine 4 trimethylation, and RNA polymerase II occupancy on PR-B promoter, without changes in DNA methylation and hydroxymethylation. In contrast, there were no estradiol-dependent changes in PR-A expression that could be related with the epigenetic marks or the transcription factors evaluated. We demonstrate that PR isoforms are differentially regulated by estradiol and that the induction of PR-B expression is associated to specific transcription factors interactions and epigenetic changes in its promoter in embryonic hypothalamic cells.
authors.affiliation: Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Av. Universidad 3000, Coyoacán, 04510, Mexico, DF, Mexico.
authors.forename: Edgar Ricardo
authors.initials: ER
authors.lastname: Vázquez-Martínez
authors.affiliation: Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Av. Universidad 3000, Coyoacán, 04510, Mexico, DF, Mexico.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Camacho-Arroyo
authors.affiliation: Departamento de Bioquímica, Facultad de Medicina, UNAM, Mexico, Mexico.
authors.forename: Angel
authors.initials: A
authors.lastname: Zarain-Herzberg
authors.affiliation: Instituto Nacional de Salud Pública, SSA, Cuernavaca, Mexico.
authors.forename: María Carmen
authors.initials: MC
authors.lastname: Rodríguez
authors.affiliation: Instituto Nacional de Geriatría, SSA, Cuernavaca, DF, Mexico.
authors.forename: Luciano
authors.initials: L
authors.lastname: Mendoza-Garcés
authors.affiliation: Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, UNAM, Mexico, Mexico.
authors.forename: Patricia
authors.initials: P
authors.lastname: Ostrosky-Wegman
authors.affiliation: Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Av. Universidad 3000, Coyoacán, 04510, Mexico, DF, Mexico. mcerbon85@yahoo.com.mx.
authors.forename: Marco
authors.initials: M
authors.lastname: Cerbón
mesh_terms: D000818:Animals; D002460:Cell Line; D019175:DNA Methylation / Q000187:drug effects; D004622:Embryo, Mammalian; D053595:Embryonic Stem Cells / Q000187:drug effects / Q000378:metabolism; D044127:Epigenesis, Genetic / Q000187:drug effects; D004958:Estradiol / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D007031:Hypothalamus / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D051379:Mice; D058953:Neural Stem Cells / Q000187:drug effects* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D020033:Protein Isoforms / Q000235:genetics; D011980:Receptors, Progesterone / Q000235:genetics* / Q000378:metabolism
chemical_list: D020033:Protein Isoforms; D011980:Receptors, Progesterone; D004958:Estradiol
keywords: Epigenetic marks; Estradiol; Histone acetylation; Hypothalamus; Progesterone receptor isoforms; Transcription factors