Shirohzu H, Yamaza H, Fukumaki Y
Division of Disease Genes, Kyushu University, Fukuoka, Japan.
Int J Hematol. 2000 Jul;72(1):28-33.
Hemoglobin (Hb) E is the most common Hb variant among Southeast Asian populations. The mutation in codon 26 (GAG to AAG) of the beta-globin gene (beta E) induces alternative splicing, resulting in the production of normally and aberrantly spliced beta-globin mRNA. Compound heterozygosity for beta-thalassemia and HbE, beta-thalassemia/HbE disease, could lead to a severe thalassemia phenotype. Repression of aberrant splicing from the beta E mutation could ameliorate the severity in such patients. We showed that the aberrant splicing was partially repressed in cells treated with antisense oligoribonucleotide targeted to the aberrant 5' splice site. The maximum effect of the antisense oligoribonucleotide was observed at a concentration of 0.4 mumol/L, 36 hours after the treatment in our experiment. We also analyzed the effect of the transient and stable expression of SF2/ASF on aberrant splicing in cells expressing the beta E-globin gene. Partial repression of the aberrant splicing was also observed in both expression systems. Our results imply that antisense oligoribonucleotide treatment and SF2/ASF expression are possible therapeutic applications for beta-thalassemia/HbE disease.
血红蛋白E（HbE）是东南亚人群中最常见的血红蛋白变异体。β-珠蛋白基因（βE）第26密码子（从GAG突变为AAG）的突变会诱导异常剪接，导致正常剪接和异常剪接的β-珠蛋白mRNA产生。β地中海贫血和HbE的复合杂合子，即β地中海贫血/HbE病，可导致严重的地中海贫血表型。抑制βE突变导致的异常剪接可改善此类患者的病情严重程度。我们发现，用靶向异常5'剪接位点的反义寡核糖核苷酸处理的细胞中，异常剪接受到部分抑制。在我们的实验中，处理36小时后，反义寡核糖核苷酸在浓度为0.4μmol/L时观察到最大效应。我们还分析了SF2/ASF瞬时和稳定表达对表达βE-珠蛋白基因的细胞中异常剪接的影响。在两种表达系统中均观察到异常剪接受到部分抑制。我们的结果表明，反义寡核糖核苷酸处理和SF2/ASF表达可能是治疗β地中海贫血/HbE病的有效方法。
