Ca(2+)-dependent annexin self-association on membrane surfaces.
Ca(2+)-dependent annexin self-association on membrane surfaces.
复制标题
Ca(2 ) 依赖性膜联蛋白在膜表面的自缔合。
DOI：
10.1021/bi00104a007
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发表时间：
1991
期刊：
影响因子：
2.9
通讯作者：
Creutz,CE
中科院分区：
文献类型：
--
作者：
Zaks,WJ;Creutz,CE
药理学系，弗吉尼亚大学，夏洛茨维尔，弗吉尼亚州22908接收1991年6月14日摘要：膜联蛋白自缔合研究与90光散射和共振能量转移之间的荧光素（供体）和曙红（受体）标记的蛋白质。Synexin（膜联蛋白VII）、p32（膜联蛋白IV）和p67（膜联蛋白VI）在溶液中以Ca 2+依赖的方式自我缔合。然而，这种活性是相当不稳定的，特别是对p32和p67，并没有一贯观察到。当结合到嗜铬颗粒膜上时，这三种蛋白质一致地自我缔合，并且在比溶液中所需低约10倍的Ca 2+水平（pCa 5.0-4.5）下这样做。含有磷脂酰丝氨酸和磷脂酰乙醇胺（1：1或1：3）的磷脂囊泡在支持膜联蛋白聚合方面不如含有磷脂酰丝氨酸和磷脂酰胆碱（1：0，1：1或1：3）的那些有效。膜联蛋白结合嗜铬颗粒膜在一个积极的合作的方式下，膜联蛋白自协会观察到的条件下，这两种现象都被抑制三氟拉嗪。由p32或synexin诱导的Ca 2+依赖性嗜铬颗粒膜聚集，在低于pCa 4的Ca 2+水平下与膜间膜联蛋白聚合相关，但在较高的Ca 2+浓度下不相关，这表明膜联蛋白自缔合可能是低Ca 2+水平下膜接触所必需的，但在较高的Ca 2+水平下不相关，在较高的Ca 2+水平下膜联蛋白可能作为单体结合两个膜。e膜联蛋白是一组新描述的同源蛋白，以Ca 2+依赖性方式结合磷脂膜[综述参见Klee（1988），以及Burgoyne和Geisow（1989）]。该组的一些成员通常也称为脂皮质素（Huang et al.，1986），cal-pactin（Glenney，1986），chromobindins（Creutz等，1983，1987）、钙电蛋白（Sudhof等人，1984），或胎盘抗凝蛋白（Tait et al.，1988年）。目前，已经鉴定了该基因家族的10个不同成员，即termedannexins IX（Pepinsky et al.，1988; Burns等人，1989; Haupt-mann等人，1989;约翰斯顿等人，1990年）。它们的氨基酸序列的比较揭示了一个共同的结构主题：每个蛋白质都有两个区域，一个是长度可变的氨基末端区域，与家族其他成员缺乏同源性，另一个是核心区域，由4个或8个重复的70个氨基酸结构域组成，家族成员之间有40-60%的同源性。
Department of Pharmacology, University of Virginia, Charlottesville, Virginia 22908 Received June 14, 1991 abstract: Annexin self-association was studied with 90 light scattering and resonance energy transfer between fluorescein (donor) and eosin (acceptor) labeled proteins. Synexin (annexin VII), p32 (annexin IV), and p67 (annexin VI) self-associated in a Ca2+-dependent manner in solution. However, thisactivity was quite labile and, especially for p32 and p67, was not consistently observed. When bound to chromaffin granule membranes, the three proteins consistently self-associated and did so at Ca2+ levels (pCa 5.0-4.5) approximately 10-fold lower than required when in solution. Phospholipid vesicles containing phosphatidylserine and phosphatidylethanolamine (1: 1 or 1: 3) were less effective at supporting annexin polymerization than were those containing phosphatidylserine and phosphatidylcholine (1: 0, 1: 1, or 1: 3). The annexins bound chromaffin granule membranes in a positively cooperative manner under conditions where annexin self-association was observed, and both phenomena were inhibited by trifluoperazine. Ca2+-dependent chromaffin granule membrane aggregation, induced by p32 or synexin, was associated with intermembrane annexin polymerization at Ca2+ levels less than pCa 4, but not at higher Ca2+ concentrations, suggesting that annexin self-association may be necessary for membrane contact at low Ca2+ levels but not at higher Ca2+ levelswhere the protein may bind two membranes as a monomer. e annexins are a newly described group of homologous proteins that bind phospholipid membranes in a Ca2+-dependent manner [for reviews see Klee (1988), and Burgoyne and Geisow (1989)]. Some members of this group are also commonly known as lipocortins (Huang et al., 1986), cal-pactins (Glenney, 1986), chromobindins (Creutz et al., 1983, 1987), calelectrins (Sudhof et al., 1984), or placental anticoagulant proteins (Tait et al., 1988). Currently, 10 distinct members of this gene family, termedannexins IX, have been identified (Pepinsky et al., 1988; Burns et al., 1989; Haupt-mann et al., 1989; Johnston et al., 1990). Comparison of their amino acid sequences reveals a common structural theme: Each protein has two regions, a variable-length amino-terminal region lacking homology with other members of the family and a core region of four or eight repeating 70 amino acid domains, which share 40-60% homology between family members.