Woda B A, Woodin M B
J Immunol. 1984 Nov;133(5):2767-72.
Lymphocyte membrane proteins are important in the transduction of signals across the plasma membrane. Visual and biophysical studies have shown that after ligand binding, membrane proteins may become immobile in the plane of the membrane and may cap. In intact cells, binding of cross-linking ligands to surface immunoglobulin converts it to a detergent-insoluble state (77% insoluble). This conversion is positively correlated with the transmission of a mitogenic signal. Class II histocompatibility proteins (Ia) and thy-1 remain predominantly detergent soluble (60 to 97% soluble). Insolubilized membrane proteins may be solubilized by incubating the detergent insoluble cytoskeletons with 0.34 M sucrose, 0.5 mM ATP, 0.5 mM dithiothreitol, 1 mM EDTA, or 3 X 10(-5) M DNAase I, 1 mM EDTA. To determine if the membrane-associated cytoskeleton contains the sufficient components for ligand-induced receptor insolubilization, experiments were done with a crude plasma membrane fraction. The results with whole cells or crude plasma membranes were comparable. These studies support the view that ligand-induced insolubilization of membrane proteins is due to their interaction with cytoskeletal structures.
淋巴细胞膜蛋白在跨质膜信号转导中起重要作用。视觉和生物物理研究表明，配体结合后，膜蛋白可能在膜平面内变得不可移动并可能形成帽状结构。在完整细胞中，交联配体与表面免疫球蛋白的结合将其转化为去污剂不溶性状态（77%不溶）。这种转化与促有丝分裂信号的传递呈正相关。II类组织相容性蛋白（Ia）和thy-1主要保持去污剂可溶性（60%至97%可溶）。通过用0.34M蔗糖、0.5mM ATP、0.5mM二硫苏糖醇、1mM EDTA或3×10（-5）M脱氧核糖核酸酶I、1mM EDTA孵育去污剂不溶性细胞骨架，可以使不溶性膜蛋白溶解。为了确定膜相关细胞骨架是否包含配体诱导受体不溶性的足够成分，用粗质膜部分进行了实验。全细胞或粗质膜的结果是可比的。这些研究支持这样一种观点，即配体诱导的膜蛋白不溶性是由于它们与细胞骨架结构的相互作用。
