Loss of feedback control of hydroxymethylglutaryl coenzyme A reductase in hepatomas.
نویسندگان
چکیده
THE FEEDBACK RESPONSE OF MEVALONATE: NADP oxidoreductase (acylating CoA; EC 1.1.1.34) in two varieties of hepatoma has been examined. In marked contrast to the feedback inhibition of this enzyme that is regularly observed in normal liver, the feedback control is completely lost in minimal-deviation hepatomas 9121 and 3924A. This finding provides the first specific biochemical localization of the defect in cholesterol feedback control, which has been shown previously to be a characteristic of all hepatomas.
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Regulation of 3-hydroxy-3-methylglutaryl-coenzyme A reductase in rat liver and Morris hepatomas 5123C, 9618A and 5123t.c.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 68 2 شماره
صفحات -
تاریخ انتشار 1971