Kopito R R, Lee B S, Simmons D M, Lindsey A E, Morgans C W, Schneider K
Department of Biological Sciences, Stanford University, California 94305-5020.
Cell. 1989 Dec 1;59(5):927-37. doi: 10.1016/0092-8674(89)90615-6.
We have isolated AE3, a novel gene expressed primarily in brain neurons and in heart. The predicted AE3 polypeptide shares a high degree of identity with the anion exchange and cytoskeletal binding domains of the erythrocyte band 3 protein. Expression of AE3 cDNA in COS cells leads to chronic cytoplasmic acidification and to chloride- and bicarbonate-dependent changes in intracellular pH, confirming that this gene product is an anion exchanger. Characterization of an AE3 mutant lacking the NH2-terminal 645 amino acids demonstrates that the COOH-terminal half of the polypeptide is both necessary and sufficient for correct insertion into the plasma membrane and for anion exchange activity. The NH2-terminal domain may play a role in regulating the activity of the exchanger and may be involved in the structural organization of the cytoskeleton in neurons.
我们分离出了AE3，这是一种主要在脑神经元和心脏中表达的新基因。预测的AE3多肽与红细胞带3蛋白的阴离子交换和细胞骨架结合结构域具有高度的同源性。AE3 cDNA在COS细胞中的表达导致慢性细胞质酸化以及细胞内pH值依赖于氯离子和碳酸氢根的变化，证实该基因产物是一种阴离子交换体。对缺失氨基末端645个氨基酸的AE3突变体的表征表明，多肽的羧基末端一半对于正确插入质膜和阴离子交换活性而言既是必需的也是足够的。氨基末端结构域可能在调节交换体的活性中发挥作用，并且可能参与神经元中细胞骨架的结构组织。
