Ideguchi H, Okubo K, Ishikawa A, Futata Y, Hamasaki N
Department of Clinical Chemistry and Laboratory Medicine, School of Medicine, Fukuoka University, Japan.
Br J Haematol. 1992 Sep;82(1):122-5. doi: 10.1111/j.1365-2141.1992.tb04603.x.
Band 3-Memphis is the most common variant of erythrocyte band 3 protein, in which a single amino acid substitution (Lys56-->Glu) in a cytoplasmic domain of band 3 has been found. We showed here that the prevalence of the variant was particularly higher in the Japanese population than that in other populations. The calculated gene frequency of the variant in Japanese was 0.156, which was about 4 times higher than that in Caucasian. Although it has been generally accepted that the cytoplasmic domain of band 3 bears no relation to anion transport activity, we found that the transport rate of phosphoenolpyruvate in erythrocytes of homozygotes was decreased to about 80% of that in control cells, and that of heterozygotes was at an intermediate level. The evidence indicates that some structural changes in the cytoplasmic domain of band 3 may have influence on the conformation of anion transport system.
3型孟菲斯带是红细胞带3蛋白最常见的变体，其中已发现带3细胞质结构域中有单个氨基酸取代（赖氨酸56→谷氨酸）。我们在此表明，该变体在日本人群中的患病率尤其高于其他人群。该变体在日本人中的计算基因频率为0.156，约为白种人的4倍。尽管人们普遍认为带3的细胞质结构域与阴离子转运活性无关，但我们发现纯合子红细胞中磷酸烯醇丙酮酸的转运速率降至对照细胞的约80%，杂合子的转运速率处于中间水平。证据表明，带3细胞质结构域的某些结构变化可能会影响阴离子转运系统的构象。
