Control of membrane fusion by phospholipid head groups. I. Phosphatidate/phosphatidylinositol specificity.
Control of membrane fusion by phospholipid head groups. I. Phosphatidate/phosphatidylinositol specificity.
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通过磷脂头基控制膜融合。
DOI：
10.1016/0005-2736(81)90179-6
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Papahadjopoulos,D
中科院分区：
文献类型：
--
作者：
Sundler,R;Papahadjopoulos,D
我们研究了由磷脂酸盐和磷脂酰肌醇单独组成的大单层囊泡以及在与其他自然产生的磷脂混合时的融合特性。融合是通过添加钙或镁诱导的，并通过检测水泡内容物的混合来监测。用羧基荧光素荧光去猝灭法测定囊泡内容物的释放。用90°光散射法监测聚集性。结果表明，不同囊泡的融合能力存在显著差异。磷脂酸盐囊泡在钙离子和镁离子同时存在时融合，阈值浓度分别为0.03-0.1 mM(钙)和0.07-0.15 mM(镁)，取决于介质的pH，8.5-6.0。相反，磷脂酰肌醇囊泡即使在50 mM的浓度下也不能与钙或镁离子融合，尽管这两种阳离子在5-10 mM范围内都能诱导聚集。即使当这两种磷脂与磷脂酰丝氨酸、磷脂酰乙醇胺和磷脂酰胆碱以2：2：4：2的摩尔比混合时，在融合能力方面仍有很大差异。从膜融合的分子机制和磷脂酰肌醇向磷脂酸盐的代谢相互转化作为膜融合现象的开关控制系统的可能作用进行了讨论。
We have studied the characteristics of fusion of large unilamellar vesicles composed of phosphatidate and phosphatidylinositol alone and in mixtures with other naturally occurring phospholipids. Fusion was induced by the addition of Ca 2+ or Mg 2+ and was monitored by detecting the mixing of aqueous vesicle contents. Release of vesicle contents was measured by dequenching of carboxyfluorescein fluorescence. Aggregation was monitored by 90° light scattering. The results indicated striking differences with respect to the fusion capacity of the different vesicles. Phosphatidate vesicles fuse in the presence of both Ca 2+ and Mg 2+ at threshold concentration ranges of 0.03–0.1 mM (Ca 2+) and 0.07–0.15 mM (Mg 2+) depending on the pH of the medium, 8.5-6.0, respectively. In contrast, phosphatidylinositol vesicles do not fuse with either Ca 2+ or Mg 2+ even at 50 mM concentrations, in spite of aggregation induced by both cations in the range of 5–10 mM. A large difference in terms of fusion capacity is retained even when these two phospholipids are mixed with phosphatidylserine, phosphatidylethanolamine and phosphatidylcholine in 2: 2: 4: 2 molar ratios. The results are discussed in terms of the molecular mechanism of membrane fusion and the possible role of the metabolic interconversion of phosphatidylinositol to phosphatidate as an on-off control system for membrane fusion phenomena involved in secretion.
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磷脂酰丝氨酸和混合磷脂酰丝氨酸-磷脂酰胆碱囊泡的融合。
DOI：
--
发表时间：
1979
期刊：
Biochimica et Biophysica Acta
影响因子：
--
作者：
S. T. Sun;C. C. Hsang;E. Day;J. Ho
通讯作者：
J. Ho
DOI：
--
发表时间：
1981
期刊：
Biochimica et Biophysica Acta
影响因子：
--
作者：
N. Düzgüneş;J. Wilschut;R. Fraley;D. Papahadjopoulos
通讯作者：
D. Papahadjopoulos
暴露于凝血酶或离子载体 A23187 的血小板中花生四烯酸的动员。
影响因子：
15.9
作者：
S. Rittenhouse;D. Deykin
通讯作者：
D. Deykin
影响因子：
2.9
作者：
J. Wilschut;N. Düzgüneş;D. Papahadjopoulos
通讯作者：
J. Wilschut;N. Düzgüneş;D. Papahadjopoulos
通过 31P NMR 研究钙诱导的混合磷脂酰胆碱-磷脂酸囊泡的聚集和融合。
DOI：
--
发表时间：
1978
期刊：
Biochimica et Biophysica Acta
影响因子：
--
作者：
M. Koter;B. de Kruijff;L. van Deenen
通讯作者：
L. van Deenen