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:1973
卷号:70
期号:7
页码:2162-2166
DOI:10.1073/pnas.70.7.2162
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase (EC 1.1.1.34 ), the rate-limiting enzyme of hepatic cholesterol biosynthesis, is suppressed in human fibroblasts cultured in the presence of serum. This enzyme activity increases by more than 10-fold after the removal of serum from the medium. The rise in enzyme activity requires de novo protein synthesis and is not accompanied by changes in the activities of several other cellular enzymes. The factor responsible for the suppression of 3-hydroxy-3-methylglutaryl coenzyme A reductase activity in cultured fibroblasts is present in the sera of at least four mammalian species, and in human serum it is found in the low-density lipoproteins. Human high-density lipoproteins, very low-density lipoproteins from chicken egg yolk, and the fraction of human serum containing no lipoproteins do not suppress the activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase.
关键词:cholesterol biosynthesis ; enzyme suppression and stimulation ; low-density and high-density lipoproteins