Protein 4.2 is critical to CD47-membrane skeleton attachment in human red cells
Protein 4.2 is critical to CD47-membrane skeleton attachment in human red cells
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DOI：
10.1182/blood-2003-04-1331
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发表时间：
2004-02-01
期刊：
影响因子：
20.3
通讯作者：
Discher, DE
中科院分区：
文献类型：
--
作者：
Dahl, KN;Parthasarathy, R;Discher, DE
缺乏蛋白 4.2 的人红细胞 (RBC) 中整合膜蛋白 CD47 的表达减少表明蛋白 4.2 可能介导 CD47 与膜骨架的连接。我们使用荧光成像微变形比较了正常细胞和蛋白质 4.2 缺陷细胞中膜骨架附着的 CD47、Rh 相关糖蛋白 (RhAG)、Rh 和带 3 的分数。我们发现 CD47 附着从正常细胞中的 55% 减少到 4.2 缺陷细胞中的 25% 至 35%。 RhAG 已被证明在所研究的细胞中表达没有显着变化，但在 4.2 缺陷细胞中，膜骨架附着显着减少，从 60% 降至 40%。 Rh 和条带 3 均显示表达没有变化，但显示出较小的下降，从正常红细胞中的 75% 附着到 4.2 缺陷细胞中的 55% 附着。在正常细胞中，Rh 表型影响 CD47 表达，但不影响 CD47 膜骨架附着水平。相反，结果表明蛋白 4.2 强烈影响 CD47 水平以及红细胞中膜骨架附着的程度，而蛋白 4.2 对 RhAG、Rh 和带 3 的膜骨架附着的影响较小。
The reduction in expression of the integral membrane protein CD47 in human red blood cells (RBCs) deficient in protein 4.2 suggests that protein 4.2 may mediate a linkage of CD47 to the membrane skeleton. We compared the fractions of membrane skeleton-attached CD47, Rh-associated glycoprotein (RhAG), Rh, and band 3 in normal and protein 4.2-deficient cells using fluorescence-imaged microdeformation. We found that CD47 attachment decreases from 55% in normal cells to 25% to 35% in 4.2-deficient cells. RhAG, which has been shown to have no significant variation in expression among the cells studied, shows a significant decrease in membrane skeleton attachment in 4.2-deficient cells from 60% to 40%. Both Rh and band 3, which have also been shown to have no change in expression, show a smaller decrease from 75% attached in normal RBCs to 55% attached in 4.2-deficient cells. In normal cells, Rh phenotype influences CD47 expression but not the level of membrane skeleton attachment of CD47. In contrast, the results indicate that protein 4.2 strongly influences CD47 levels as well as the extent of membrane skeleton attachment in the RBC, whereas protein 4.2 affects membrane skeletal attachment of RhAG, Rh, and band 3 to a lesser extent.