title: Chromatin immunoprecipitation-mediated target identification proved aquaporin 5 is regulated directly by estrogen in the uterus.
abstract: Estrogens play a central role in the reproduction of vertebrates and affect a variety of biological processes. The major target molecules of estrogens are nuclear estrogen receptors (ERs), which have been studied extensively at the molecular level. In contrast, our knowledge of the genes that are regulated directly by ERs remains limited, especially at the level of the whole organism rather than cultured cells. In order to identify genes that are regulated directly by ERs in vivo, we used estrogen treated mouse uterus and performed chromatin immunoprecipitation. Sequence analysis of a precipitated DNA fragment enabled alignment with the mouse genomic sequence and revealed that the promoter region of the gene encoding aquaporin 5 (AQP5) was precipitated with antibody against ER alpha. Quantitative PCR and DNA microarray analyses confirmed that AQP5 is activated soon after administration of estrogen. In addition, the promoter region of AQP5 contained a functional estrogen response element that was activated directly by estrogen. Although several AQP genes are expressed in the uterus, only direct activation of AQP5 could be detected following treatment with estrogen. This chromatin immunoprecipitation-mediated target identification may be applicable to the study of other transcription factor networks.
authors.affiliation: Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, 444-8787, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Eri
authors.initials: E
authors.lastname: Takahashi
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Miyagawa
authors.forename: Hajime
authors.initials: H
authors.lastname: Watanabe
authors.forename: Taisen
authors.initials: T
authors.lastname: Iguchi
mesh_terms: D000818:Animals; D051402:Aquaporin 5 / Q000235:genetics*; D001483:Base Sequence; D047369:Chromatin Immunoprecipitation; D004247:DNA / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D004958:Estradiol / Q000494:pharmacology*; D047628:Estrogen Receptor alpha / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D020411:Oligonucleotide Array Sequence Analysis; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D014599:Uterus / Q000187:drug effects* / Q000378:metabolism*
chemical_list: C496038:Aqp5 protein, mouse; D051402:Aquaporin 5; D017931:DNA Primers; D047628:Estrogen Receptor alpha; D004958:Estradiol; D004247:DNA