Functional evidence for presence of lipid rafts in erythrocyte membranes:: Gsα in rafts is essential for signal transduction
Functional evidence for presence of lipid rafts in erythrocyte membranes:: Gsα in rafts is essential for signal transduction
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DOI：
10.1002/ajh.21126
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发表时间：
2008-05-01
影响因子：
12.8
通讯作者：
Takakuwa, Yuichi
中科院分区：
文献类型：
--
作者：
Kamata, Kotoe;Manno, Sumie;Takakuwa, Yuichi
富含胆固醇和鞘脂并含有特定膜蛋白的膜微区被称为脂筏。脂筏参与了多种细胞类型的细胞信号传导途径。异源三聚体鸟嘌呤核苷酸结合蛋白（Gs α）已被证明是红细胞的筏组分，并参与细胞信号传导。筏被分离为耐洗涤剂微区（DRM）用于生化分析。胆固醇消耗被广泛用于破坏筏结构，以研究它们在生物膜中的功能。在本研究中，我们开发了一种替代策略，在不改变膜胆固醇含量的情况下破坏筏结构。盐酸利多卡因是一种两亲性局部麻醉剂，可可逆性破坏红细胞膜上的筏，改变Gsa依赖的信号转导途径。这些发现提供了筏的存在，同时保持正常的胆固醇含量在红细胞膜的证据，并确认筏相关的Gs α在红细胞的信号转导中的作用。
Membrane microdomains enriched in cholesterol and sphingolipids and containing specific membrane proteins are designated as lipid rafts. Lipid rafts have been implicated in cell signaling pathways in various cell types. Heterotrimeric guanine nucleotide-binding protein (Gs alpha) has been shown to be a raft component of erythrocytes and has been implicated in cell signaling. Rafts are isolated as detergent-resistant microdomains (DRMs) for biochemical analysis. Cholesterol depletion is widely used to disrupt raft structures to study their function in biological membranes. In the present study, we developed an alternate strategy for disrupting raft structures without altering membrane cholesterol content. Lidocaine hydrochloride, an amphipathic local anesthetic, is shown to reversibly disrupt rafts in erythrocyte membranes and alter the Gsa dependent signal transduction pathway. These findings provide evidence for the presence of rafts while maintaining normal cholesterol content in erythrocyte membranes and confirm a role for raft-associated Gs alpha in signal transduction in erythrocytes.