Kiefer C R, Trainor J F, McKenney J B, Valeri C R, Snyder L M
Department of Immunology and Microbiology, Medical College of Georgia, Augusta, USA.
Blood. 1995 Jul 1;86(1):366-71.
The irreducible complexation of hemoglobin with spectrin is a natural phenomenon of red blood cell aging, positively correlating with increasing cell density and decreasing cell deformability. The current study begins to address the role of these complexes in the disruption of membrane skeletal physiology and structure. The effect of bound hemoglobin on spectrin dimer self-association was investigated in vitro. The extent of conversion of isolated spectrin dimers to tetramers was evaluated as a function of peroxide-induced globin complexation before the conversion incubations. The incremental accumulation of tetramer was observed to decrease with increasing peroxide concentration used in the globin complexation step. The role of oxidized heme in this process was made apparent by the inability of carboxyhemoglobin to inhibit tetramer accumulation. A Western blot analysis of naturally formed globin-spectrin conjugates demonstrated irreducible complexes of globin with both bands 1 and 2. The complexes are tentatively designated "h1" and "h2". This analysis also demonstrated that h1 is completely extractable from cell ghosts, whereas h2 is only 50% extractable. These findings are incorporated into a hypothesis linking globin-spectrin complexation and the consequent inhibition of spectrin dimer self-association to the clustered band 3 senescence antigen (Low et al, Science 227:531, 1985).
血红蛋白与血影蛋白的不可还原络合是红细胞衰老的自然现象，与细胞密度增加和细胞变形性降低呈正相关。当前研究开始探讨这些复合物在破坏膜骨架生理学和结构中的作用。在体外研究了结合的血红蛋白对血影蛋白二聚体自缔合的影响。在转化孵育之前，将分离的血影蛋白二聚体转化为四聚体的程度作为过氧化物诱导的珠蛋白络合的函数进行评估。观察到随着珠蛋白络合步骤中使用的过氧化物浓度增加，四聚体的增量积累减少。羧基血红蛋白无法抑制四聚体积累，这表明氧化血红素在该过程中的作用。对天然形成的珠蛋白 - 血影蛋白缀合物的蛋白质印迹分析表明，珠蛋白与带1和带2均形成不可还原的复合物。这些复合物暂定为“h1”和“h2”。该分析还表明，h1可从细胞血影中完全提取，而h2仅50%可提取。这些发现被纳入一个假设，该假设将珠蛋白 - 血影蛋白络合以及随之而来的血影蛋白二聚体自缔合抑制与聚集的带3衰老抗原联系起来（Low等人，《科学》227:531，1985）。
