Spectral imaging to measure heterogeneity in membrane lipid packing.
Spectral imaging to measure heterogeneity in membrane lipid packing.
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DOI：
10.1002/cphc.201402794
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发表时间：
2015-05-18
期刊：
影响因子：
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通讯作者：
Eggeling C
中科院分区：
文献类型：
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作者：
Sezgin E;Waithe D;Bernardino de la Serna J;Eggeling C
质膜的物理化学特性已被证明在细胞功能中发挥重要作用。在这些特性中，脂质的分子顺序或脂质堆积非常重要。人们认为脂质堆积的变化通过启动蛋白质的聚结和构象变化来划分细胞信号传导。推断膜脂质堆积的常见方法是使用膜嵌入的极性敏感染料，其发射光谱取决于直接膜环境的分子顺序。在这里，我们报告了对极性敏感染料发射光谱中此类光谱位移的改进测定。这一改进基于扫描共焦荧光显微镜上的光谱成像与改进的分析的结合，该分析考虑整个发射光谱而不是仅考虑单个波长范围。使用这种方法和极性敏感染料 C-Laurdan 或 Di-4-ANEPPDHQ，我们能够高精度地对模型和细胞膜的脂质堆积的微小差异进行成像。
Physicochemical properties of the plasma membrane have been shown to play an important role in cellular functionality. Among those properties, the molecular order of the lipids, or the lipid packing, is of high importance. Changes in lipid packing are believed to compartmentalize cellular signaling by initiating coalescence and conformational changes of proteins. A common way to infer membrane lipid packing is by using membrane-embedded polarity-sensitive dyes, whose emission spectrum is dependent on the molecular order of the immediate membrane environment. Here, we report on an improved determination of such spectral shifts in the emission spectrum of the polarity-sensitive dyes. This improvement is based on the use of spectral imaging on a scanning confocal fluorescence microscope in combination with an improved analysis, which considers the whole emission spectrum instead of just single wavelength ranges. Using this approach and the polarity-sensitive dyes C-Laurdan or Di-4-ANEPPDHQ, we were able to image—with high accuracy—minute differences in the lipid packing of model and cellular membranes.