Approximately 11% of monogenic diseases involve nonsense mutations that are caused by premature termination codons. These codons can in principle be read-through via the site-specific incorporation of unnatural amino acids to generate full-length proteins with minimal loss of function. Here we report that aminoacyl-tRNA-synthase–tRNA pairs specific for the desired unnatural amino acids can be used to read through a nonsense mutation in the dystrophin gene. We show partial restoration of dystrophin expression in differentiated primary myoblasts (from a mdx mouse model and a patient with Duchenne muscular dystrophy), and restoration of muscle function in two mouse models: mdx mice, via viral delivery of the engineered tRNA-synthase–tRNA pair intraperitoneally or intramuscularly and of the associated unnatural amino acid intraperitoneally; and mice produced by crossing mdx mice and transgenic mice with a chromosomally integrated pair, via intraperitoneal delivery of the unnatural amino acid. The incorporation of unnatural amino acids to restore endogenous protein expression could be explored for therapeutic use.

大约 11% 的单基因疾病涉及由提前终止密码子引起的无义突变。这些密码子原则上可以通过非天然氨基酸的位点特异性掺入来读取，以产生功能损失最小的全长蛋白质。在这里，我们报告了特定于所需非天然氨基酸的氨酰-tRNA-合酶-tRNA 对可用于读取肌营养不良蛋白基因中的无义突变。我们展示了分化的原代成肌细胞（来自mdx小鼠模型和 Duchenne 肌营养不良症患者）中肌营养不良蛋白表达的部分恢复，以及两种小鼠模型中肌肉功能的恢复：mdx小鼠，通过腹膜内或肌肉内的工程化 tRNA-合酶-tRNA 对和腹膜内相关的非天然氨基酸的病毒递送；通过非天然氨基酸的腹膜内递送，将mdx小鼠和具有染色体整合对的转基因小鼠杂交产生的小鼠。可以探索掺入非天然氨基酸以恢复内源性蛋白质表达以用于治疗用途。