Ellis L, Morgan D O, Jong S M, Wang L H, Roth R A, Rutter W J
Proc Natl Acad Sci U S A. 1987 Aug;84(15):5101-5. doi: 10.1073/pnas.84.15.5101.
A hybrid receptor molecule composed of the extracellular ligand-binding domain of the human insulin receptor and the transmembrane and cytoplasmic (protein-tyrosine kinase) domains of the chicken sarcoma virus UR2 transforming protein p68gag-ros has been constructed and expressed in Chinese hamster ovary (CHO) cells. The hybrid is processed normally into alpha and hybrid beta subunits, is expressed on the cell surface at high levels, and binds insulin with near-wild-type affinity. Furthermore, insulin stimulates the phosphorylation on tyrosine residues of the hybrid beta subunit in vivo and the phosphorylation of an exogenous substrate [poly(Glu,Tyr)] in vitro. Thus the hybrid is capable of heterologous transmembrane signaling. However, the hybrid mediates neither the insulin-activated uptake of 2-deoxyglucose nor the incorporation of [3H]thymidine into DNA, suggesting that the physiological response(s) mediated by ligand-activated protein-tyrosine kinases may utilize distinct intracellular mechanisms for postreceptor signaling.
一种由人胰岛素受体的细胞外配体结合结构域与鸡肉瘤病毒UR2转化蛋白p68gag-ros的跨膜和细胞质（蛋白酪氨酸激酶）结构域组成的杂合受体分子已构建成功，并在中国仓鼠卵巢（CHO）细胞中表达。该杂合体正常加工成α亚基和杂合β亚基，在细胞表面高水平表达，并以接近野生型的亲和力结合胰岛素。此外，胰岛素在体内刺激杂合β亚基酪氨酸残基的磷酸化，并在体外刺激外源底物[聚（Glu，Tyr）]的磷酸化。因此，该杂合体能够进行异源跨膜信号传导。然而，该杂合体既不介导胰岛素激活的2-脱氧葡萄糖摄取，也不介导[3H]胸苷掺入DNA，这表明配体激活的蛋白酪氨酸激酶介导的生理反应可能利用不同的细胞内机制进行受体后信号传导。
