Open AccessLoss of Feedback Control of Hydroxymethylglutaryl Coenzyme A Reductase in Hepatomas
Author(s) -
Marvin D. Siperstein,
Ann M. Gyde,
Harold P. Morris
Publication year - 1971
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.68.2.315
Subject(s) - reductase , coenzyme a , feedback control , enzyme , cofactor , biochemistry , chemistry , biology , control engineering , engineering
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.