Protein-sphingolipid interactions within cellular membranes
Protein-sphingolipid interactions within cellular membranes
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DOI：
10.1194/jlr.d700023-jlr200
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发表时间：
2008-01-01
影响因子：
6.5
通讯作者：
Bruegger, Britta
中科院分区：
文献类型：
--
作者：
Haberkant, Per;Schmitt, Oliver;Bruegger, Britta
每个细胞内细胞器都严重依赖于维持其特定的脂质成分，这反过来又有助于细胞膜的生物物理特性。随着我们对具有不同脂质成分的明确微域的膜组织的了解不断增加，关于给定蛋白质的微域的靶向/分离的分子机制的问题出现了。除了作为分配基础的特定脂质跨膜片段相互作用之外，给定微域的存在可能会改变蛋白质的构象，从而改变调节修饰的活性和可用性。然而，对于大多数蛋白质来说，跨膜片段的特定脂质环境及其与蛋白质功能和整体膜组织的相关性在很大程度上是未知的。为了帮助填补这一空白，我们合成了一种新型光活性鞘脂前体，与磷酸甘油脂前体和光胆固醇一起，在体内研究了特定蛋白质跨膜跨脂质相互作用。作为原理证明，我们展示了鞘脂探针对神经酰胺转运蛋白的特异性标记，并描述了脂质与 Caveolin-1、磷脂酰肌醇转运蛋白 β 和尼卡斯特林成熟形式的体内特异性相互作用。这种新型的光不稳定鞘脂探针可以检测活细胞膜双层内的蛋白质-鞘脂相互作用。
Each intracellular organelle critically depends on maintaining its specific lipid composition that in turn contributes to the biophysical properties of the membrane. With our knowledge increasing about the organization of membranes with defined microdomains of different lipid compositions, questions arise regarding the molecular mechanisms that underlie the targeting to/segregation from microdomains of a given protein. In addition to specific lipid-transmembrane segment interactions as a basis for partitioning, the presence in a given microdomain may alter the conformation of proteins and, thus, the activity and availability for regulatory modifications. However, for most proteins, the specific lipid environment of transmembrane segments as well as its relevance to protein function and overall membrane organization are largely unknown. To help fill this gap, we have synthesized a novel photoactive sphingolipid precursor that, together with a precursor for phosphoglycerolipids and with photo-cholesterol, was investigated in vivo with regard to specific protein transmembrane span-lipid interactions. As a proof of principle, we show specific labeling of the ceramide transporter with the sphingolipid probe and describe specific in vivo interactions of lipids with caveolin-1, phosphatidylinositol transfer protein beta, and the mature form of nicastrin. This novel photolabile sphingolipid probe allows the detection of protein-sphingolipid interactions within the membrane bilayer of living cells.