ATP-DEPENDENT ASYMMETRIC DISTRIBUTION OF SPIN-LABELED PHOSPHOLIPIDS IN THE ERYTHROCYTE-MEMBRANE - RELATION TO SHAPE CHANGES
ATP-DEPENDENT ASYMMETRIC DISTRIBUTION OF SPIN-LABELED PHOSPHOLIPIDS IN THE ERYTHROCYTE-MEMBRANE - RELATION TO SHAPE CHANGES
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DOI：
10.1073/pnas.81.12.3751
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发表时间：
1984-01-01
期刊：
影响因子：
--
通讯作者：
DEVAUX, PF
中科院分区：
文献类型：
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作者：
SEIGNEURET, M;DEVAUX, PF
用自旋标记的磷脂酰胆碱、磷脂酰丝氨酸和磷脂酰乙醇胺类似物研究了人红细胞膜磷脂的横向扩散和不对称性。抗坏血酸还原用于评估标签的跨双层分布。所有3种自旋标记的磷脂最初均掺入膜的外小叶中。在新鲜红细胞上，5 ℃。C，磷脂酰胆碱标记主要保留在外瓣叶中。磷脂酰丝氨酸和磷脂酰乙醇胺标签进行快速横向扩散，导致其不对称分布，有利于内部小叶。后一种效应被可逆地抑制后ATP耗尽的红细胞，并可以重现resealed红细胞鬼，只有当水解镁-ATP被包括在内部介质。ATP驱动的氨基磷脂向内叶的运输可能是红细胞膜磷脂不对称的主要原因。同样的机制也解释了维持红细胞膜盘状的ATP需求。
Spin-labeled analogs of phosphatidylcholine, phosphatidlyserine and phosphatidylethanolamine were used to study phospholipid transverse diffusion and asymmetry in the human erythrocyte membrane. Ascorbate reduction was used to assess the transbilayer distribution of the labels. All 3 spin-labeled phospholipids initially incorporated into the outer leaflet of the membrane. On fresh erythrocytes at 5.degree. C, the phosphatidylcholine label remained mainly in the outer leaflet. The phosphatidylserine and phosphatidylethanolamine labels underwent rapid transverse diffusion that led to their asymmetric distribution in favor of the inner leaflet. The latter effect was reversibly inhibited after ATP depletion of the erythrocytes and could be reproduced on resealed erythrocyte ghosts only if hydrolyzable Mg-ATP was included in the internal medium. An ATP-driven transport of amino phospholipids toward the inner leaflet could be the major cause of the phospholipid asymmetry in the erythrocyte membrane. The same mechanism were explain the ATP requirement of the maintenance of the erythrocyte membrane discoid shape.