Alloisio N, Dalla Venezia N, Rana A, Andrabi K, Texier P, Gilsanz F, Cartron J P, Delaunay J, Chishti A H
CNRS URA 1171, Faculté de Médecine Grange-Blanche, Lyon, France.
Blood. 1993 Aug 15;82(4):1323-7.
Human erythrocyte p55 is a peripheral membrane protein that contains three distinct domains in its primary structure: an N-terminal domain, an SH3 motif, and a C-terminal guanylate kinase domain. We used naturally mutated red blood cells (RBCs) with primary genetic defects resulting in the absence of protein 4.1 (4.1[-] hereditary elliptocytosis) or glycophorin C (Leach elliptocytosis). The absence of either protein was associated with the absence of p55. On a stoichiometric basis, the reduction in glycophorin C (about 80%) was concomitant to the lack of p55 in RBCs devoid of protein 4.1. Similarly, the reduction of protein 4.1 (about 20%) was equivalent to the absence of p55 in RBCs devoid of glycophorin C. These correlations suggest that p55 is associated, in precise proportions, with the protein 4.1-glycophorin-C complex, linking the skeleton and the membrane. The protein 4.1-glycophorin-C cross-bridge is known to be critically important for the stability and mechanical properties of human RBC plasma membrane. Because isoforms of protein 4.1, glycophorin C, and p55 exist in many tissues, these results provide evidence of a linkage between the skeleton and the membrane that may have implications in many nonerythroid cells.
人红细胞p55是一种外周膜蛋白，其一级结构包含三个不同的结构域：一个N端结构域、一个SH3基序和一个C端鸟苷酸激酶结构域。我们使用了具有原发性遗传缺陷的天然突变红细胞（RBC），这些缺陷导致蛋白4.1（4.1[-]遗传性椭圆形红细胞增多症）或血型糖蛋白C（利奇椭圆形红细胞增多症）缺失。这两种蛋白中任何一种的缺失都与p55的缺失相关。从化学计量学角度来看，在缺乏蛋白4.1的红细胞中，血型糖蛋白C的减少（约80%）与p55的缺乏同时出现。同样，在缺乏血型糖蛋白C的红细胞中，蛋白4.1的减少（约20%）等同于p55的缺失。这些相关性表明，p55以精确的比例与蛋白4.1-血型糖蛋白C复合物相关联，连接着骨架和膜。已知蛋白4.1-血型糖蛋白C跨桥对于人红细胞质膜的稳定性和机械性能至关重要。由于蛋白4.1、血型糖蛋白C和p55的异构体存在于许多组织中，这些结果为骨架和膜之间的联系提供了证据，这可能对许多非红细胞细胞有影响。
