Characterization of anion transport system in trout red blood cell.
Characterization of anion transport system in trout red blood cell.
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鳟鱼红细胞阴离子转运系统的表征。
DOI：
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发表时间：
1984
影响因子：
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通讯作者：
H. Passow
中科院分区：
文献类型：
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作者：
L. Romano;H. Passow
鳟鱼红细胞中的阴离子运输是由一种膜蛋白介导的，该膜蛋白选择性地结合二氢-4,4'-二硫氰二苯乙烯-2,2'-二磺酸（3H2DIDS），并在十二烷基硫酸钠(SDS)-聚丙烯酰胺凝胶电泳图上形成与哺乳动物红细胞中带3蛋白相同位置的弥散结构带。H2DIDS与该蛋白的结合与抑制阴离子平衡交换之间存在线性关系。在最大的抑制作用下，大约8 X 10(6)个分子/细胞与蛋白质结合。鳟鱼红细胞中阴离子运输的动力学不同于哺乳动物红细胞。除了硫酸盐转运的h2dids敏感组分外，还存在相当大的h2dids不敏感组分，其相对大小随温度升高而降低。在23摄氏度时，其含量约为25%。h2dids敏感成分的温度依赖性约为15千卡/摩尔，而不是人红细胞中的32千卡/摩尔。Cl-输运随pH的增加而增加。pH高于7.4时，输运速率变得太快，用抑制剂停止或过滤技术都无法测量。在pH 6.5到7.8的范围内，SO2-4的转运几乎与pH无关，在没有二氧化碳的情况下，SO2-4与细胞内Cl-交换的净进入伴随着很少的质子摄取。净质子吸收只有在温度高于40摄氏度时才能测量。可能在更低和更生理的温度下，鳟鱼红细胞中的能带3蛋白完成了部分SO2-4的运动，而没有共同运输质子。
Anion transport in the trout red blood cell is mediated by a membrane protein that selectively binds dihydro-4,4'-dithiocyanostilbene-2,2'-disulfonic acid (3H2DIDS) and that forms on sodium dodecyl sulfate (SDS)-polyacrylamide gel electropherograms a band with the same diffuse structure at the same location as the band 3 protein of the mammalian red blood cells. There exists a linear relationship between binding of H2DIDS to this protein and the inhibition of anion equilibrium exchange. At maximal inhibition about 8 X 10(6) molecules/cell are bound to the protein. The kinetics of anion transport in the trout red blood cell differ from those of mammalian red blood cells. In addition to a H2DIDS-sensitive component of sulfate transport there exists a considerable H2DIDS-insensitive component with a relative magnitude that decreases with increasing temperature. At 23 degrees C, it amounts to about 25%. The temperature dependence of the H2DIDS-sensitive component is about 15 kcal/mol instead of 32 as in human red blood cells. Cl- transport increases with increasing pH. Above pH 7.4, the rate of transport becomes too fast to be measurable with either inhibitor stop or filtration technique. SO2-4 transport is nearly pH independent over the pH range 6.5 to 7.8 and the net entry of SO2-4 in exchange against intracellular Cl-, as followed in the absence of CO2, is accompanied by little if any proton uptake. Net proton uptake becomes measurable only at temperatures above 40 degrees C. Possibly at lower and more physiological temperatures, the band 3 protein in the red blood cell of the trout accomplishes part of the SO2-4 movements without cotransporting protons.