, Volume 50, Issue 10, pp 927–936 | Cite as

Electron Transfer Pathways in Cholesterol Synthesis



Cholesterol synthesis in the endoplasmic reticulum requires electron input at multiple steps and utilizes both NADH and NADPH as the electron source. Four enzymes catalyzing five steps in the pathway require electron input: squalene monooxygenase, lanosterol demethylase, sterol 4α-methyl oxidase, and sterol C5-desaturase. The electron-donor proteins for these enzymes include cytochrome P450 reductase and the cytochrome b5 pathway. Here I review the evidence for electron donor protein requirements with these enzymes, the evidence for additional electron donor pathways, and the effect of deletion of these redox enzymes on cholesterol and lipid metabolism.


Squalene monooxygenase Sterol 4α-methyl oxidase CYP51 Sterol C5-desaturase Cytochrome P450 reductase Cytochrome b5 Cytochrome b5 reductase 


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© AOCS 2015

Authors and Affiliations

  1. 1.Department of Pharmaceutical Sciences, College of PharmacyUniversity of KentuckyLexingtonUSA

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