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：1979
卷号：76
期号：1
页码：323-327
DOI：10.1073/pnas.76.1.323
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The coincident expression of two structurally distinct isoenzymes of human alkaline phosphatase was demonstrated in two independently derived gestational choriocarcinoma cell lines. These proteins were shown to have enzymatic, antigenic, and physical-chemical properties resembling those of isoenzymes from term placenta and adult liver. The regulation of these isoenzymes has been studied during the exposure of both cell lines to 5-bromodeoxyuridine and dibutyryl cyclic AMP. The responses of the alkaline phosphatase isoenzymes to these agents have also been compared with the response of another protein phenotypic to placenta, the alpha subunit of chorionic gonadotropin. The results show that (i) the separate structural genes coding for placental and liver alkaline phosphatases are regulated in a noncoordinate fashion; (ii) both alkaline phosphatase genes respond independently of the alpha subunit; and (iii) the induction of the placental type isoenzyme occurs via at least two independent pathways.
