caa a22 4500 397555369 CHVBK 20180308164800.0 cr unu---uuuuu 161202e199602 xx s 000 0 eng 10.1093/oxfordjournals.jbchem.a021238 doi (NATIONALLICENCE)oxford-10.1093/oxfordjournals.jbchem.a021238 Significance of the Chromatin Structure in Expression of the Rat Prolactin Gene [Elektronische Daten] [Akira Aizawa, Koji Kazahari, Tadashi Yoneyama, Masao Ono] To elucidate the mechanisms underlying cell type-specific expression of the growth hormone (GH) and prolactin (PRL) genes, we used rat pituitary-derived cell lines producing exclusively GH (GC cells) or PRL (235 cells), and examined the following: expression of transcription factors essential for GH and/or PRL gene expression; promoter/enhancer activity of the GH and PRL genes transiently introduced by transfection; and chromatin structures of the GH and PRL genes. Even in PRL-nonproducing GC cells, the PRL promoter/enhancer was more active than the GH promoter, and the transcription factors, Pit-1 and estrogen receptor (ER), essential for PRL gene expression were functional. The PRL promoter/enhancer of GC cells was normal. On DNase I sensitivity analysis of the chromatin structure, two hypersensitive sites were detected in PRL gene chromatin of PRL-producing 235 cells but none in that of GC cells. It thus follows that the major reason for absence of the expression of the endogenous PRL gene1 in GC cells is neither the lack of transcription factors necessary for PRL gene expression nor an anomaly of the PRL gene itself, but that the chromatin structure of the PRL gene differs in PRL-nonproducing and -producing cells. It was shown in this study that neither Pit-1 nor ER is required for conversion of the structure of PRL gene chromatin to a DNase I-hypersensitive state. © by the Journal of Biochemistry Regular Papers nationallicence chromatin structure nationallicence DNase I-hypersensitivity nationallicence gene expression nationallicence prolactin nationallicence transcription factor nationallicence Aizawa Akira Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut Kazahari Koji Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut Yoneyama Tadashi Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut Ono Masao Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut The Journal of Biochemistry Oxford University Press 119/2(1996-02), 296-301 0021-924X 119:2<296 1996 119 jbchem https://doi.org/10.1093/oxfordjournals.jbchem.a021238 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/oxfordjournals.jbchem.a021238 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Aizawa Akira Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut NATIONALLICENCE 700 1- Kazahari Koji Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut NATIONALLICENCE 700 1- Yoneyama Tadashi Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut NATIONALLICENCE 700 1- Ono Masao Departments of Molecular Biology Kitasato University, Sagamihara, Kanagawa 228 aut NATIONALLICENCE 773 0- The Journal of Biochemistry Oxford University Press 119/2(1996-02), 296-301 0021-924X 119:2<296 1996 119 jbchem Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford