Cholesterol Biosynthesis in Liver Tissue
Most of the early stages of cholesterol biosynthesis in liver tissue are now well defined with regard to control sites, intermediates, and specific enzymes (e.g. (1)). In contrast much basic information is still to be obtained for the stages of cholesterol biosynthesis after squalene cyclization. The purpose of this report is to review recent findings in our laboratory which elucidate mechanisms of liver enzymes catalyzing conversion of squalene and sterol intermediates to cholesterol. In particular, we identified a liver protein which functions uniquely as carrier for water insoluble precursors during cholesterol biosynthesis. This protein is designated squalene and sterol carrier protein or SCP. In this report we describe the properties of SCP; its role as activator of reactions catalyzed by microsomal enzymes; its specificity; and the inhibition of its binding and activation functions by inhibitors of cholesterol biosynthesis.
KeywordsBile Acid Liver Tissue Cholesterol Biosynthesis Microsomal Enzyme Liver Protein
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