Role of N-myristylation in targeting of band 4.2 (pallidin) in nonerythroid cells.
Role of N-myristylation in targeting of band 4.2 (pallidin) in nonerythroid cells.
复制标题
N-肉豆蔻酰化在非红系细胞中靶向带 4.2（苍白球蛋白）中的作用。
DOI：
10.1006/excr.1996.0387
复制
发表时间：
1996
影响因子：
3.7
通讯作者：
Cohen,CM
中科院分区：
文献类型：
--
作者：
Risinger,MA;Korsgren,C;Cohen,CM
条带4.2（苍白蛋白）是一种主要的红细胞膜蛋白，已在许多非红细胞类型中检测到。越来越多的证据表明，能带4.2参与维持红细胞的膜稳定性。例如，能带4.2与整体膜蛋白能带3和红细胞膜上的细胞骨架蛋白结合，能带4.2缺乏导致不同程度的溶血性贫血。我们以前已经表明，人红细胞带4.2在其倒数第二甘氨酸上是肉芽化的。在这里，我们报告当在Sf9和COS细胞中表达时，在细胞内不同位置检测到带4.2的肉芽化形式，而不是非肉芽化形式。我们还发现，未剪接的人红细胞带4.2（网织红细胞中的一种次要形式，在前三个n端氨基酸之后比主要红系形式多含有30个氨基酸）仅在几乎无法检测到的水平上发生肉芽化，而小鼠红细胞带4.2（与人类红系带4.2的主要红系形式同源）的肉芽化水平与人类带4.2相当。这些结果表明，肉豆蔻化在4.2条带靶向到细胞内特定位置的过程中起着关键作用，并可能在该蛋白的功能中发挥作用。
Band 4.2 (pallidin) is a major erythrocyte membrane protein which has been detected in a number of nonerythroid cell types. Increasing evidence suggests that band 4.2 is involved in maintaining membrane stability in the erythrocyte. For example, band 4.2 binds to the integral membrane protein band 3 and to cytoskeletal proteins in the erythrocyte membrane, and band 4.2 deficiency results in varying degrees of hemolytic anemia. We have previously shown that human erythrocyte band 4.2 is myristylated at its penultimate glycine. Here we report that when expressed in both Sf9 and COS cells, myristylated forms of band 4.2 are detected at different intracellular locations than nonmyristylated forms. We also show that the unspliced form of human erythrocyte band 4.2 (a minor form in reticulocytes which contains an additional 30 amino acids after the first three N-terminal amino acids compared to the major erythroid form) is myristylated only at a barely detectable level, while mouse erythrocyte band 4.2 (homologous to the major erythroid form of human band 4.2) is myristylated at a level comparable to that of human band 4.2. These results suggest that myristylation plays a key role in the targeting of band 4.2 to specific intracellular locations and is likely to have a role in the function of this protein.