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The Control of Cholesterol Homeostasis: Regulation of HMG CoA Reductase

  • K. L. Luskey
Conference paper

Abstract

Cholesterol homeostasis within cells is regulated so as to provide adequate cholesterol without building up excessive stores. Two regulated pathways account for this cholesterol. The LDL receptor pathway mediates the uptake of cholesterol-containing lipoproteins from the plasma by receptor-mediated endocytosis. The endogenous cholesterol synthetic pathway which converts acetyl CoA to cholesterol via a multi-enzyme pathway is regulated by changes in the activity of HMG CoA reductase. Changes in the expression of HMG CoA reductase have been shown to affect the expression of LDL receptors both in cultured cells as well as in intact animals [1, 2]. To better understand the mechanisms that control cholesterol homeostasis, the means by which HMG CoA reductase is regulated have been studied. In cells, suppression of HMG CoA reductase activity by cholesterol is accomplished by at least two mechanisms:
  1. 1.

    decreased transcription of the HMG CoA reductase gene

     
  2. 2.

    enhanced degradation of the reductase protein.

     

Keywords

Cholesterol Homeostasis Eukaryotic mRNAs Reductase Protein Excessive Store Amino Acid Substitution Rate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • K. L. Luskey
    • 1
  1. 1.Department of Molecular GeneticsUniversity of Texas Health Science CenterDallasUSA

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