Ultrafast diffusion of a fluorescent cholesterol analog in compartmentalized plasma membranes.
Ultrafast diffusion of a fluorescent cholesterol analog in compartmentalized plasma membranes.
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DOI：
10.1111/tra.12163
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发表时间：
2014-06
期刊：
影响因子：
--
通讯作者：
Fujiwara TK
中科院分区：
文献类型：
--
作者：
Hiramoto-Yamaki N;Tanaka KA;Suzuki KG;Hirosawa KM;Miyahara MS;Kalay Z;Tanaka K;Kasai RS;Kusumi A;Fujiwara TK
人们对质膜 (PM) 中胆固醇的分布和动态知之甚少。最近开发的 Bodipy488 缀合胆固醇分子 (Bdp-Chol) 使我们能够使用单荧光分子成像来研究 PM 中的胆固醇行为。令人惊讶的是，在完整的 PM 中，Bdp-Chol 的扩散速度是 PM 中任何分子中最快的，中值扩散系数 (D) 为 3.4 µm2/秒，比非筏磷脂分子 (0.33 µm2/秒) 大约 10 倍，尽管 Bdp-Chol 可能与筏结构域相关。此外，Bdp-Chol 在超过 0.5 毫秒的时间尺度内没有表现出捕获的迹象。在起泡的 PM 中，肌动蛋白丝大量耗尽，Bdp-Chol 和 Cy3-缀合的二油酰磷脂酰乙醇胺 (Cy3-DOPE) 以相当的 Ds 扩散（中位数分别 = 5.8 和 6.2 µm2/秒），表明基于肌动蛋白的膜骨架仅将 Bdp-Chol 的 D 降低了起泡中的约 2 倍PM，而它将 Cy3-DOPE 的 D 降低约 20 倍。这些结果与之前提出的模型一致，其中PM被基于肌动蛋白的膜骨架栅栏及其相关的跨膜纠察蛋白划分，用于所有膜分子的宏观扩散，并且表明Bdp-Chol一旦进入边界，穿过隔室边界的概率比Cy3-DOPE大~10倍。由于隔室尺寸大于假定的筏域的尺寸，因此我们得出结论，筏域与膜骨架诱导的隔室共存并包含在其中。
Cholesterol distribution and dynamics in the plasma membrane (PM) are poorly understood. The recent development of Bodipy488-conjugated cholesterol molecule (Bdp-Chol) allowed us to study cholesterol behavior in the PM, using single fluorescent-molecule imaging. Surprisingly, in the intact PM, Bdp-Chol diffused at the fastest rate ever found for any molecules in the PM, with a median diffusion coefficient (D) of 3.4 µm2/second, which was ∼10 times greater than that of non-raft phospholipid molecules (0.33 µm2/second), despite Bdp-Chol's probable association with raft domains. Furthermore, Bdp-Chol exhibited no sign of entrapment in time scales longer than 0.5 milliseconds. In the blebbed PM, where actin filaments were largely depleted, Bdp-Chol and Cy3-conjugated dioleoylphosphatidylethanolamine (Cy3-DOPE) diffused at comparable Ds (medians = 5.8 and 6.2 µm2/second, respectively), indicating that the actin-based membrane skeleton reduces the D of Bdp-Chol only by a factor of ∼2 from that in the blebbed PM, whereas it reduces the D of Cy3-DOPE by a factor of ∼20. These results are consistent with the previously proposed model, in which the PM is compartmentalized by the actin-based membrane-skeleton fence and its associated transmembrane picket proteins for the macroscopic diffusion of all of the membrane molecules, and suggest that the probability of Bdp-Chol passing through the compartment boundaries, once it enters the boundary, is ∼10× greater than that of Cy3-DOPE. Since the compartment sizes are greater than those of the putative raft domains, we conclude that raft domains coexist with membrane-skeleton-induced compartments and are contained within them.
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DOI：
10.1073/pnas.0511026103
发表时间：
2006-02-14
影响因子：
11.1
作者：
Gambin, Y;Lopez-Esparza, R;Urbach, W
通讯作者：
Urbach, W
影响因子：
7.8
作者：
Fujiwara, Takahiro;Ritchie, Ken;Murakoshi, Hideji;Jacobson, Ken;Kusumi, Akihiro
通讯作者：
Kusumi, Akihiro
DOI：
10.1016/s0006-291x(02)00905-1
发表时间：
2002-08-23
影响因子：
3.1
作者：
Estronca, LMBB;Moreno, MJ;Vaz, WLC
通讯作者：
Vaz, WLC
影响因子：
64.5
作者：
Goswami, Debanjan;Gowrishankar, Kripa;Mayor, Satyajit
通讯作者：
Mayor, Satyajit
影响因子：
2.9
作者：
ALMEIDA, PFF;VAZ, WLC;THOMPSON, TE
通讯作者：
THOMPSON, TE