mRNA therapeutics offer a potentially universal strategy for the efficient development and delivery of therapeutic proteins. Current mRNA vaccines include chemically modified nucleotides to reduce cellular immunogenicity. Here, we develop an efficient, high-throughput method to measure human translation initiation on therapeutically modified as well as endogenous RNAs. Using systems-level biochemistry, we quantify ribosome recruitment to tens of thousands of human 5′ untranslated regions (UTRs) including alternative isoforms and identify sequences that mediate 200-fold effects. We observe widespread effects of coding sequences on translation initiation and identify small regulatory elements of 3–6 nucleotides that are sufficient to potently affect translational output. Incorporation of N1-methylpseudouridine (m1Ψ) selectively enhances translation by specific 5′ UTRs that we demonstrate surpass those of current mRNA vaccines. Our approach is broadly applicable to dissecting mechanisms of human translation initiation and engineering more potent therapeutic mRNAs.

中文翻译：

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人类翻译起始的定量分析揭示了有效调节内源性和治疗修饰 mRNA 的元件


mRNA 疗法为治疗性蛋白质的高效开发和递送提供了一种潜在的通用策略。目前的 mRNA 疫苗包括化学修饰的核苷酸，以降低细胞免疫原性。在这里，我们开发了一种高效、高通量的方法来测量治疗修饰和内源性 RNA 的人类翻译起始。使用系统级生物化学，我们量化了核糖体募集到数以万计的人类 5' 非翻译区 （UTR），包括替代亚型，并鉴定了介导 200 倍效应的序列。我们观察到编码序列对翻译起始的广泛影响，并确定了足以有效影响翻译输出的 3-6 个核苷酸的小调节元件。N1-甲基假尿嘧啶 （m1Ψ） 的掺入选择性地增强了特定 5' UTR 的翻译，我们证明这超过了当前 mRNA 疫苗的翻译。我们的方法广泛适用于剖析人类翻译起始的机制和设计更有效的治疗性 mRNA。