[Regulation of gene expression by cholesterol and macrophage scavenger receptor].
Cellular cholesterol level is strictly regulated by the synthesis and the incorporation of cholesterol. Cholesterol synthetic enzymes and lipoprotein receptors are regulated mainly at the transcriptional level. Recently, sterol regulatory element binding proteins (SREBPs) which induce LDL receptor expression, were cloned and the mechanism of sterol-mediated gene regulation was proposed. Cholesterol synthesizing enzymes such as HMG-CoA reductase, farnesyl pyrophosphate synthase and squalene synthase are also regulated by the cellular cholesterol level, but it is suggested that SREBPs are not play critical role in their regulation. Scavenger receptors also uptake cholesterol into macrophage, but the receptors are not regulated by the cellular cholesterol level and this leads to the abnormal accumulation of cholesterol in macrophages.
3rd Department of Internal Medicine, University of Tokyo.
Y
Y
Kawabe
H
H
Itakura
T
T
Kodama
D019883:Alkyl and Aryl Transferases; D000818:Animals; D001483:Base Sequence; D002784:Cholesterol / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D051231:Farnesyltranstransferase; D005786:Gene Expression Regulation; D006801:Humans; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism*; D008969:Molecular Sequence Data; D011973:Receptors, LDL / Q000235:genetics*; D013261:Sterols / Q000378:metabolism; D014166:Transferases / Q000378:metabolism
D004268:DNA-Binding Proteins; D011973:Receptors, LDL; D013261:Sterols; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D014166:Transferases; D019883:Alkyl and Aryl Transferases; D051231:Farnesyltranstransferase