Cholesterols domains

Pandit, S.A., Vasudevan, S., Chiu, S.W., Mashl, R.J., Jakobsson, E., Scott, H.L. Sphingomyelin-cholesterol domains in phospholipid membranes atomistic simulation. Biophys. J. 2004, 87, 1092-100. 

FIGURE 10.4 Cholesterol domain (consisting of 107 molecules) as studied by AFM. (a) Image 5 m x 5 m (b) three-dimensional image (see text for details). The size of image is... 

Apart of forming the bilayer, membrane lipids exhibit dynamic structures within the lamellas, forming microdomains with specific functionalities. The so called membrane rafts are sphingolipid-cholesterol domains that contribute to signal transduction, as well as to lipid and protein sorting and transport [18]. 

Schroeder F, Woodford JK, Kavecansky J, Wood WG, Joiner, C. Cholesterol domains in biological membranes. Mol Membr Biol 1995 12 113-119. 

Schroeder F, Jefferson JR, Kier AB, Knittel J, Scallen TJ, Wood WG, etal. Membrane cholesterol dynamics cholesterol domains and kinetic pools. Proc Soc Exp Biol Med 1991 196 235-252. 

Gallegos, A.M., McIntosh, A.L., Atshaves, B.R, Schroeder, F. 2004. Structure and cholesterol domain dynamics of an enriched caveolaeAipid raft isolate. Biochem. J. 382 451-461. 

I, 2-naphthoquinone stimulates lipid peroxidation and cholesterol domain formation in model membranes. Investigative Ophthalmology Visual Science 54 7189-7197. 

Sostarecz, A. G., McQuaw, C. M., Ewing, A. G., Winograd, N. (2004) Phosphatidyle-thanolamine-induced cholesterol domains chemically identified with mass spectrometric imaging. J Am Chem Soc, 126, 13882-13883. 

Folate conjugated with either cholesterol or DSPE was incorporated into lipo-plexes formulated with DOTAP/cholesterol (wt/wt 31/69) that possess cholesterol nanodomains. The presence of the folate ligand within the cholesterol domain promotes more productive transfection in cultured cells, and intracellular trafficking of the lipoplexes after entry into cells plays a crucial role in gene delivery (Xu and Anchordoquy 2010). 

Wood, W.G., Schroeder, F., Igbavboa, U., Avdulov, N.A. Chochina, S.V (2002). Brain membrane cholesterol domains, aging and amyloid beta-peptides. Neurobiology of Aging, 23, 685-694. 

Several groups have studied the structure of chiral phases illustrated in Fig. IV-15 [167,168]. These shapes can be understood in terms of an anisotropic line tension arising from the molecular symmetry. The addition of small amounts of cholesterol reduces X and produces thinner domains. Several studies have sought an understanding of the influence of cholesterol on lipid domain shapes [168,196]. 

Fig. XV-8. Fluorescence micrographs of crystalline domains of an S-DPPC monolayer containing 2% cholesterol and compressed to the plateau region. [From H. McConnell, D. Keller, and H. Gaub, J. Phys. Chetn., 40, 1717 (I486) (Ref, 49). Copyright 1986, American Chemical Society.]...

The breast cancer resistance protein (BCRP) belongs to the G-branch of the ABC-transporter family (ABCG2). In contrast to most other ABC-proteins, BCRP consists of only one transmembrane domain (TDM) with one nucleotide binding fold (NBF) at its C-terminus. Because of this structural characteristic BCRP as well as other ABC-transporters with only one TMD are termed half transporters. To achieve functional activity these transporters have to form hetero- or homodimers. BCRP is involved in the multidrug resistance of certain tumors and transports endogenous compounds like cholesterol and steroid hormones. 

Jessup W, Gelissen IC, Gaus K, Kritharides L (2006) Roles of ATP binding cassette transporters Al and Gl, scavenger receptor BI and membrane lipid domains in cholesterol export from macrophages. Curr Opin Lipidol 17(3) 247-57... 

Recently, due to increased interest in membrane raft domains, extensive attention has been paid to the cholesterol-dependent liquid-ordered phase in the membrane (Subczynski and Kusumi 2003). The pulse EPR spin-labeling DOT method detected two coexisting phases in the DMPC/cholesterol membranes the liquid-ordered and the liquid-disordered domains above the phase-transition temperature (Subczynski et al. 2007b). However, using the same method for DMPC/lutein (zeaxanthin) membranes, only the liquid-ordered-like phase was detected above the phase-transition temperature (Widomska, Wisniewska, and Subczynski, unpublished data). No significant differences were found in the effects of lutein and zeaxanthin on the lateral organization of lipid bilayer membranes. We can conclude that lutein and zeaxanthin—macular xanthophylls that parallel cholesterol in its function as a regulator of both membrane fluidity and hydrophobicity—cannot parallel the ability of cholesterol to induce liquid-ordered-disordered phase separation. 

FIGURE 10.12 The mole ratio of carotenoid/phospholipid and carotenoid/total lipid (phospholipid + cholesterol) in raft domain (detergent-resistant membrane, DRM) and bulk domain (detergent-soluble membrane, DSM) isolated from membranes made of raft-forming mixture (equimolar ternary mixture of dioleoyl-PC (DOPC)/sphingomyelin/cholesterol) with 1 mol% lutein (LUT), zeaxanthin (ZEA), P-cryptoxanthin (P-CXT), or P-carotene (P-CAR). 

Cholesterol-poor Cholesterol-rich domain domain... 

FIGURE 10.14 Schematic drawing showing the localization of xanthophyll molecules in the cholesterol-rich (raft or DRM) domain and the cholesterol-poor (bulk or DSM) domain. Unfavorable interaction with cholesterol in the cholesterol-rich domain is indicated. 

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