Relationship of lipid rafts to transient confinement zones detected by single particle tracking
Relationship of lipid rafts to transient confinement zones detected by single particle tracking
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DOI：
10.1016/s0006-3495(02)75393-9
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发表时间：
2002-01-01
影响因子：
3.4
通讯作者：
Jacobson, K
中科院分区：
文献类型：
--
作者：
Dietrich, C;Yang, B;Jacobson, K
我们研究了在C3 H 10 T1/2小鼠成纤维细胞膜内移动的分子的单粒子轨迹中检测到的瞬态限制区（TCZ）的物理和化学特征及其与“筏”的关系。“我们研究了不同膜分子的侧向运动，这些分子被认为在不同程度上进入或离开推定的脂质结构域（称为筏）。我们发现，与Thy-1（一种糖基磷脂酰肌醇锚定蛋白）和GM 1（一种鞘糖脂）相比，脂质类似物在TCZ中的时间显著减少。对于Thy-1，我们发现胆固醇提取显著降低了区域丰度，这表明所观察到的临时限制的主要来源与筏域的存在有关。对颗粒轨迹的更详细的分析表明，即使在原始逃逸后几十秒，区域也可以重新访问，并且区域内的扩散减少了约2倍，这与该区域是富含胆固醇的液体有序相一致。令人惊讶的是，瞬态约束并不强烈的温度依赖性。总的来说，我们的数据表明，C3 H细胞质膜的某些区域存在筏相关结构域，其可以持续数十秒。
We examined the physical and chemical characteristics of transient confinement zones (TCZs) that are detected in single particle trajectories of molecules moving within the membrane of C3H 10T1/2 murine fibroblasts and their relationship to "rafts." We studied the lateral movement of different membrane molecules thought to partition to varying degrees into or out of the putative lipid domains known as rafts. We found that lipid analogs spend significantly less time in TCZs compared with Thy-1, a glycosylphosphatidylinositol-anchored protein, and GM1, a glycosphingolipid. For Thy-1, we found that zone abundance was markedly reduced by cholesterol extraction, suggesting that a major source of the observed temporary confinement is related to the presence of raft domains. More detailed analysis of particle trajectories reveals that zones can be revisited even tens of seconds after the original escape and that diffusion within the zones is reduced by a factor of similar to2, consistent with the zone being a cholesterol-rich liquid-ordered phase. Surprisingly, transient confinement was not strongly temperature dependent. Overall, our data demonstrate that there are raft-related domains present in certain regions of the plasma membrane of C3H cells, which can persist for tens of seconds.