PDF(Pubmed)
Abstract：
A wide spectrum of SLC26A4 mutations causes Pendred syndrome and enlarged vestibular aqueduct, both associated with sensorineural hearing loss (SNHL). A splice-site mutation, c.919-2A>G (A-2G), which is common in Asian populations, impairs the 3\' splice site of intron 7, resulting in exon 8 skipping during pre-mRNA splicing and a subsequent frameshift that creates a premature termination codon in the following exon. Currently, there is no effective drug treatment for SHNL. For A-2G-triggered SNHL, molecules that correct mis-splicing of the mutant hold promise to treat the disease. Antisense oligonucleotides (ASOs) can promote exon inclusion when targeting specific splicing silencers. Here, we systematically screened a large number of ASOs in a minigene system and identified a few that markedly repressed exon 8 skipping. A lead ASO, which targets a heterogeneous nuclear ribonucleoprotein (hnRNP) A1/A2 intronic splicing silencer (ISS) in intron 8, promoted efficient exon 8 inclusion in cultured peripheral blood mononuclear cells derived from two homozygous patients. In a partially humanized Slc26a4 A-2G mouse model, two subcutaneous injections of the ASO at 160 mg/kg significantly rescued exon 8 splicing in the liver. Our results demonstrate that the ISS-targeting ASO has therapeutic potential to treat genetic hearing loss caused by the A-2G mutation in SLC26A4.
摘要：
广泛的SLC26A4突变导致Pendred综合征和扩大的前庭水管，两者都与感音神经性听力损失（SNHL）有关。剪接位点突变,c.919-2A>G（A-2G），这在亚洲人群中很常见，损害内含子7的3'剪接位点，导致外显子8在mRNA剪接前和随后的移码过程中发生跳跃，从而在随后的外显子中产生过早的终止密码子。目前,目前尚没有有效的药物治疗方法。对于A-2G触发的SNHL，纠正突变体错误剪接的分子有望治疗这种疾病。反义寡核苷酸（ASO）可以在靶向特异性剪接沉默时促进外显子包含。这里,我们在小基因系统中系统地筛选了大量的ASO，并确定了一些显着抑制外显子8跳跃的ASO。领先的ASO，它靶向内含子8中的异质核核糖核蛋白（hnRNP）A1/A2内含子剪接沉默（ISS），促进了外显子8在来自两个纯合患者的培养外周血单核细胞中的有效包含。在部分人源化Slc26a4A-2G小鼠模型中，两次皮下注射160mg/kg的ASO可明显挽救肝脏中的外显子8剪接。我们的结果表明，ISS靶向ASO具有治疗SLC26A4中A-2G突变引起的遗传性听力损失的治疗潜力。
