Scanning STED-FCS reveals spatiotemporal heterogeneity of lipid interaction in the plasma membrane of living cells
Scanning STED-FCS reveals spatiotemporal heterogeneity of lipid interaction in the plasma membrane of living cells
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DOI：
10.1038/ncomms6412
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发表时间：
2014-11-01
影响因子：
16.6
通讯作者：
Eggeling, Christian
中科院分区：
文献类型：
--
作者：
Honigmann, Alf;Mueller, Veronika;Eggeling, Christian
脂质和蛋白质的相互作用在质膜生物活性中起着重要的作用，从它们的扩散特性中可以学到很多东西。在这里，我们提出了超分辨率STED显微镜与扫描荧光相关光谱（扫描STED- fcs， sSTED-FCS）的组合来表征脂质相互作用的时空异质性。sSTED-FCS揭示了荧光鞘脂类似物的瞬时分子相互作用热点。相互作用位点的直径小于80nm，脂质在这些区域被短暂捕获几毫秒。相比之下，新开发的具有改进相分配特性的荧光磷脂和胆固醇类似物表现出更均匀的扩散，而不依赖于对液体有序或无序膜环境的偏好。我们的研究结果不支持基于脂相分离的纳米结构域存在于我们培养的非刺激细胞的基膜中，并表明替代相互作用是我们的鞘脂类似物的强局部捕获的原因。
The interaction of lipids and proteins plays an important role in plasma membrane bioactivity, and much can be learned from their diffusion characteristics. Here we present the combination of super-resolution STED microscopy with scanning fluorescence correlation spectroscopy (scanning STED-FCS, sSTED-FCS) to characterize the spatial and temporal heterogeneity of lipid interactions. sSTED-FCS reveals transient molecular interaction hotspots for a fluorescent sphingolipid analogue. The interaction sites are smaller than 80nm in diameter and lipids are transiently trapped for several milliseconds in these areas. In comparison, newly developed fluorescent phospholipid and cholesterol analogues with improved phase-partitioning properties show more homogenous diffusion, independent of the preference for liquid-ordered or disordered membrane environments. Our results do not support the presence of nanodomains based on lipid-phase separation in the basal membrane of our cultured nonstimulated cells, and show that alternative interactions are responsible for the strong local trapping of our sphingolipid analogue.