期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：1
页码：66-70
DOI：10.1073/pnas.79.1.66
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Prolactin-specific RNA (RNAPRL) in total nuclear RNA and in cytoplasmic poly(A)+RNA isolated from GH (rat pituitary) cells was selectively hybridized to immobilized cloned cDNAPRL. Agarose gel electrophoresis of the nuclear RNAPRL sequences eluted from the nitrocellulose filters revealed several RNA species of approximately 25-30, 18-19, and 12-13 S. Only the 12-13 S RNA species could be detected in the cytoplasmic poly(A)+RNA fraction. Comparative analysis of total nuclear RNA of control and thyrotropin-releasing hormone (thyroliberin)-treated cells by the reverse Southern blot technique demonstrated increased levels of all the nuclear RNAPRL species in hormone-treated cells. Nuclear and cytoplasmic RNAPRL sequences in control and treated cells were quantitated by molecular hybridization to cloned cDNAPRL. The 2- to 3-fold stimulation of PRL production by thyrotropin-releasing hormone-treated GH4C1 cells could be correlated to the corresponding increase of nuclear RNAPRL sequences. The hybrid strain, which produces 1/5th the amount of PRL that the parent GH4C1 does, had 1/5th the amounts of nuclear RNAPRL sequences. Thyrotropin-releasing hormone affected neither prolactin production nor nuclear RNAPRL level in 928-9b cells. RNAPRL sequences could not be detected either in nuclei or in cytoplasm of prolactin nonproducing F1BGH12C1 cells. However, prolactin production could be induced and RNAPRL sequences could be detected in the total nuclear RNA and in cytoplasmic poly(A)+RNA fraction after treatment of this GH cell substrain with 5-bromodeoxyuridine. These results demonstrate that differential basal prolactin production and its modulation by thyrotropin-releasing hormone and by 5-bromodeoxyuridine can be correlated to the altered levels of nuclear RNAPRL sequences in the three GH cell strains.
