Rivnay B, Rossi G, Henkart M, Metzger H
J Biol Chem. 1984 Jan 25;259(2):1212-7.
Mast cells and related cells have on their surface receptors that bind immunoglobulin E (IgE) with high affinity and which, when aggregated, trigger exocytosis. We recently demonstrated that when these receptors are solubilized with mild detergents, their subunits dissociate unless an appropriate lipid:detergent ratio is maintained. The conditions required to maintain the receptors' integrity appeared to parallel those previously determined as necessary to obtain adequate incorporation of unpurified IgE-receptor complexes from detergent extracts into liposomes. We now show that purified IgE-receptor complexes having the full complement of subunits become preferentially inserted into liposomes. If the receptor subunits are chemically cross-linked to each other, at least some of such receptors can be incorporated, even though lipid is omitted during their purification. The findings suggest that the IgE-binding alpha subunit of the receptor is anchored to the bilayer by means of one or both of the other subunits.
肥大细胞及相关细胞表面具有能与免疫球蛋白E（IgE）高亲和力结合的受体，这些受体聚集时会触发胞吐作用。我们最近证明，当用温和去污剂使这些受体溶解时，除非维持适当的脂质与去污剂比例，其亚基会解离。维持受体完整性所需的条件似乎与之前确定的从去污剂提取物中获得足够的未纯化IgE受体复合物掺入脂质体所必需的条件相似。我们现在表明，具有完整亚基互补的纯化IgE受体复合物优先插入脂质体。如果受体亚基彼此化学交联，即使在纯化过程中省略脂质，至少部分此类受体仍可掺入。这些发现表明，受体的IgE结合α亚基通过一个或其他两个亚基锚定在双层膜上。
