IDENTIFICATION OF A 170-KDA PROTEIN ASSOCIATED WITH THE VACUOLAR NA+/H+ ANTIPORT OF BETA-VULGARIS
IDENTIFICATION OF A 170-KDA PROTEIN ASSOCIATED WITH THE VACUOLAR NA+/H+ ANTIPORT OF BETA-VULGARIS
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DOI：
10.1073/pnas.88.24.11177
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发表时间：
1991-12-01
影响因子：
11.1
通讯作者：
BLUMWALD, E
中科院分区：
文献类型：
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作者：
BARKLA, BJ;BLUMWALD, E
在生长培养基中添加阿米洛利对甜菜液泡膜囊泡Na+/H+逆向转运活性的影响进行了测试。细胞悬液在NaCl和阿米洛利存在下生长的细胞显示增加的反向转运活性。动力学数据的分析表明，而对Na+离子的亲和力的反向端口没有改变，Na+/H+交换的最大速度显着增加。这些结果表明，更多的逆向转运分子的液泡膜和/或增加的周转率的Na+/H+交换。通过阿米洛利的存在下，增加活性的反向转运与增强合成的液泡膜170-kDa的多肽。不仅在细胞暴露于阿米洛利时，而且在细胞暴露于高NaCl浓度时，检测到这种多肽的合成增加。针对170-kDa多肽的多克隆抗体几乎完全抑制了反向转运活性。这些结果表明，协会的170 kDa的多肽与液泡Na+/H+反向转运。
The effect of the addition of amiloride to the growth medium was tested on the Na+/H+ antiport activity of tonoplast vesicles isolated from sugar beet (Beta vulgaris L.) cell suspensions. Cells grown in the presence of NaCl and amiloride displayed an increased antiport activity. Analysis of the kinetic data showed that while the affinity of the antiport for Na+ ions did not change, the maximal velocity of the Na+/H+ exchange increased markedly. These results suggest the addition of more antiport molecules to the tonoplast and/or an increase in the turnover rate of the Na+/H+ exchange. The increase in activity of the antiport by the presence of amiloride was correlated with the enhanced synthesis of a tonoplast 170-kDa polypeptide. The increased synthesis of this polypeptide was detected not only upon exposure of the cells to amiloride but also when the cells were exposed to high NaCl concentrations. Polyclonal antibodies against the 170-kDa polypeptide almost completely inhibited the antiport activity. These results suggest the association of the 170-kDa polypeptide with the vacuolar Na+/H+ antiport.