Cholesterol binding

Alpy, F., Stoeckel, M. E., Dierich, A. et al. 2001. The steroidogenic acute regulatory protein homolog MLN64, a late endosomal cholesterol-binding protein. J. Biol. Chem., 276(6) 4261-4269. 

An interesting feature of many cells is the permanent presence on the plasma membrane of flask-shaped regions termed caveolae. They are abundant in certain capillary endothelial cells, and appear to have a role in cholesterol binding, although many other functions have been suggested [62]. 

VLDLs, IDLs, and LDLs are closely related to one another. VLDLs formed in the liver (see p. 312) transport triacylglycerols, cholesterol, and phospholipids to other tissues. Like chylomicrons, they are gradually converted into IDL and LDL under the influence of lipoprotein lipase [1]. This process is also stimulated by HDL. Cells that have a demand for cholesterol bind LDL through an interaction between their LDL receptor and ApoB-100, and then take up the complete particle through receptor-mediated endocytosis. This type of transport is mediated by depressions in the membrane ( coated pits"), the interior of which is lined with the protein clathrin. After LDL binding, clathrin promotes invagination of the pits and pinching off of vesicles ( coated vesicles"). The clathrin then dissociates off and is reused. After fusion of the vesicle with ly-sosomes, the LDL particles are broken down (see p. 234), and cholesterol and other lipids are used by the cells. 

One of the best therapeutic approaches may be to prevent absorption of cholesterol from the intestines by inclusion of a higher fiber content in the diet.66 Supplementation with a cholesterol-binding resin may provide additional protection. Plant sterols also interfere with cholesterol absorption. Incorporation of esters of sitostanol into margarine provides an easy method of administration. Supplemental vitamin E may also be of value.q Another effective approach is to decrease the rate of cholesterol synthesis by administration of drugs that inhibit the synthesis of cholesterol. Inhibitors of HMG-CoA reductase,s hh (e.g., vaLostatin) iso-pentenyl-PP isomerase, squalene synthase (e.g.,... 

Lund, E.D. 1984. Cholesterol binding capacity of fiber from tropical fruits and vegetables. Lipids 19, 85-90. 

Volume 51 Cholesterol Binding and Cholesterol Transport Proteins... 

Micich et al. (1992) demonstrated that polymer-supported saponins could be used to remove cholesterol from milk fat and that the polymers could be regenerated by solvent extraction without loss of cholesterol-binding capacity. 

The hypothyroid condition is associated with increased blood lipid levels, which can be treated using statins or cholesterol binding resins such as colestyramine. 

Historically, any proteinases that hydrolyze elastin have been named elastases. The genes coding for the elastases are clustered on chromosome 19, and three main types of enzymes are known (I) pancreatic El, (2) pancreatic elas-tase-2 (EC 3.4.21.71), and (3) pancreatic endopeptidase-3 (EC 3.4.21.70), also called cholesterol-binding proteinase. ... 

A. Uittenbogaard and E.J. Smart, Palmitoylation of caveolin-1 is required for cholesterol binding, chaperone complex formation, and rapid transport of cholesterol to caveolae, J. Biol. Chem., 2000,... 

The stimulation of mitochondrial pregnenolone production by adrenal cytosohc fractions has been observed repeatedly [34-38], but has not been adequately characterized. A heat-stable protein preparation has been obtained from adrenal cytoplasm [39] and has been reported to stimulate cholesterol side-chain cleavage by acetone powders of adrenal mitochondria [40]. Cholesterol-binding properties of cytosolic fractions from the adrenal and testis [41] and from ovary [41,42] have also been reported. 

Cholesterol binds SCAP SCAP binds Insig... 

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