Influence of cholesterol and ergosterol on membrane dynamics: a fluorescence approach
Influence of cholesterol and ergosterol on membrane dynamics: a fluorescence approach
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DOI：
10.1016/j.bbrc.2004.04.118
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发表时间：
2004-06-11
影响因子：
3.1
通讯作者：
Chattopadhyay, A
中科院分区：
文献类型：
--
作者：
Arora, A;Raghuraman, H;Chattopadhyay, A
甾醇是真核细胞的重要膜组分，对膜的组织和功能具有重要作用。胆固醇是高等真核生物中最具代表性的甾醇。在生物膜和模型膜中，它经常以非随机的方式分布在结构域或池中。富含胆固醇的功能微域(脂筏)通常与细胞信号和膜运输有关。有趣的是，最近也从酵母菌和果蝇等生物体中分离出脂筏，这些生物体的主要甾醇成分是麦角甾醇。虽然胆固醇对膜的影响的详细生物物理特征已经有了很好的文献，但麦角固醇对膜的组织和动力学的影响还不是很清楚。我们利用环境敏感的荧光膜探针DPH监测了胆固醇和麦角甾醇对液体相(POPC)和凝胶相(DPPC)膜动态性质的影响。我们的稳态和时间分辨荧光测量结果第一次显示了麦角甾醇和胆固醇对膜组织的不同影响。这些新的结果与含有麦角甾醇的有机体如果蝇的脂筏相关，与高等真核生物相比，果蝇保持较低的甾醇水平。(C)2004 Elsevier Inc.保留所有权利。
Sterols are essential membrane components of eukaryotic cells and are important for membrane organization and function. Cholesterol is the most representative sterol present in higher eukaryotes. It is often found distributed non-randomly in domains or pools in biological and model membranes. Cholesterol-rich functional microdomains (lipid rafts) are often implicated in cell signaling and membrane traffic. Interestingly, lipid rafts have also recently been isolated from organisms such as yeast and Drosophila, which have ergosterol as their major sterol component. Although detailed biophysical characterization of the effect of cholesterol on membranes is well documented, the effect of ergosterol on the organization and dynamics of membranes is not very clear. We have monitored the effect of cholesterol and ergosterol on the dynamic properties of both fluid (POPC) and gel (DPPC) phase membranes utilizing the environment-sensitive fluorescent membrane probe DPH. Our results from steady state and time-resolved fluorescence measurements show, for the first time, differential effects of ergosterol and cholesterol toward membrane organization. These novel results are relevant in the context of lipid rafts in ergosterol-containing organisms such as Drosophila which maintain a low level of sterol compared to higher eukaryotes. (C) 2004 Elsevier Inc. All rights reserved.