The ability to control translation of endogenous or exogenous RNAs in eukaryotic cells would facilitate a variety of biotechnological applications. Current strategies are limited by low fold changes in transgene output and the size of trigger RNAs (trRNAs). Here we introduce eukaryotic toehold switches (eToeholds) as modular riboregulators. eToeholds contain internal ribosome entry site sequences and form inhibitory loops in the absence of a specific trRNA. When the trRNA is present, eToeholds anneal to it, disrupting the inhibitory loops and allowing translation. Through optimization of RNA annealing, we achieved up to 16-fold induction of transgene expression in mammalian cells. We demonstrate that eToeholds can discriminate among viral infection status, presence or absence of gene expression and cell types based on the presence of exogenous or endogenous RNA transcripts.

控制真核细胞中内源性或外源性 RNA 翻译的能力将促进各种生物技术应用。目前的策略受到转基因输出的低倍变化和触发 RNA (trRNA) 大小的限制。在这里，我们介绍了真核生物脚趾开关 (eToeholds) 作为模块化核糖调节剂。eToeholds 包含内部核糖体进入位点序列，并在没有特定 trRNA 的情况下形成抑制环。当 trRNA 存在时，eToeholds 与它退火，破坏抑制环并允许翻译。通过优化 RNA 退火，我们在哺乳动物细胞中实现了高达 16 倍的转基因表达诱导。我们证明 eToeholds 可以区分病毒感染状态，