Ellis L, Morgan D O, Koshland D E, Clauser E, Moe G R, Bollag G, Roth R A, Rutter W J
Proc Natl Acad Sci U S A. 1986 Nov;83(21):8137-41. doi: 10.1073/pnas.83.21.8137.
A hybrid receptor has been constructed that is composed of the extracellular domain of the human insulin receptor fused to the transmembrane and cytoplasmic domains of the bacterial aspartate chemoreceptor. This hybrid protein can be expressed in rodent (CHO) cells and displays several functional features comparable to wild-type insulin receptor. It is localized to the cell surface, binds insulin with high affinity, forms oligomers, and is recognized by conformation-specific monoclonal antibodies. Although most of the expressed protein accumulates as a 180-kDa proreceptor, some processed 135-kDa receptor can be detected on the cell surface by covalent cross-linking. Expression of the hybrid receptor inhibits the insulin-activated uptake of 2-deoxyglucose by CHO cells. Thus, this hybrid is partially functional and can be processed; however, it is incapable of native transmembrane signaling. The results indicate that the intact domains of different types of receptors can retain some of the native features in a hybrid molecule but specific requirements will need to be satisfied for transmembrane signaling.
构建了一种杂合受体，它由人胰岛素受体的细胞外结构域与细菌天冬氨酸化学感受器的跨膜和细胞质结构域融合而成。这种杂合蛋白可在啮齿动物（CHO）细胞中表达，并表现出与野生型胰岛素受体相当的几种功能特性。它定位于细胞表面，以高亲和力结合胰岛素，形成寡聚体，并被构象特异性单克隆抗体识别。虽然大多数表达的蛋白以180 kDa的前体受体形式积累，但通过共价交联可在细胞表面检测到一些加工后的135 kDa受体。杂合受体的表达抑制了CHO细胞对2-脱氧葡萄糖的胰岛素激活摄取。因此，这种杂合体部分具有功能且可被加工；然而，它不能进行天然的跨膜信号传导。结果表明，不同类型受体的完整结构域在杂合分子中可保留一些天然特性，但跨膜信号传导需要满足特定要求。
