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PubMed · 16753029

Cholesterol sensing, trafficking, and esterification.

Ta-Yuan Chang·Catherine C Y Chang·Nobutaka Ohgami·Yoshio Yamauchi
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Abstract

Mammalian cells acquire cholesterol from low-density lipoprotein (LDL) and from endogenous biosynthesis. The roles of the Niemann-Pick type C1 protein in mediating the endosomal transport of LDL-derived cholesterol and endogenously synthesized cholesterol are discussed. Excess cellular cholesterol is converted to cholesteryl esters by the enzyme acyl-coenzyme A:cholesterol acyltransferase (ACAT) 1 or is removed from a cell by cellular cholesterol efflux at the plasma membrane. A close relationship between the ACAT substrate pool and the cholesterol efflux pool is proposed. Sterol-sensing domains (SSDs) are present in several membrane proteins, including NPC1, HMG-CoA reductase, and the SREBP cleavage-activating protein. The functions of SSDs are described. ACAT1 is an endoplasmic reticulum cholesterol sensor and contains a signature motif characteristic of the membrane-bound acyltransferase family. The nonvesicular cholesterol translocation processes involve the START domain proteins and the oxysterol binding protein-related proteins (ORPs). The properties of these proteins are summarized.

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Amino Acid SequenceAnimalsBiological TransportCholesterolEsterificationHumansMembrane GlycoproteinsMolecular Sequence DataPregnenoloneJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tReview

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Ta-Yuan Chang, Catherine C Y Chang, Nobutaka Ohgami, Yoshio Yamauchi. 2006. Cholesterol sensing, trafficking, and esterification.. https://doi.org/10.1146/annurev.cellbio.22.010305.104656

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