The trans-translation mechanism is a key component of multiple quality control pathways in bacteria that ensure proteins are synthesized with high fidelity in spite of challenges such as transcription errors, mRNA damage, and translational frameshifting. trans-Translation is performed by a ribonucleoprotein complex composed of tmRNA, a specialized RNA with properties of both a tRNA and an mRNA, and the small protein SmpB. tmRNA-SmpB interacts with translational complexes stalled at the 3' end of an mRNA to release the stalled ribosomes and target the nascent polypeptides and mRNAs for degradation. In addition to quality control pathways, some genetic regulatory circuits use trans-translation to control gene expression. Diverse bacteria require trans-translation when they execute large changes in their genetic programs, including responding to stress, pathogenesis, and differentiation.

中文翻译：

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翻译生物学。

转译机制是细菌中多种质量控制途径的关键组成部分，可确保蛋白质以高保真度合成，尽管存在转录错误、mRNA 损伤和翻译移码等挑战。反式翻译由核糖核蛋白复合物执行，该复合物由 tmRNA、一种具有 tRNA 和 mRNA 特性的特化 RNA 和小蛋白 SmpB 组成。tmRNA-SmpB 与停滞在 mRNA 3' 端的翻译复合物相互作用以释放停滞的核糖体并靶向新生多肽和 mRNA 进行降解。除了质量控制途径外，一些基因调控回路使用反式翻译来控制基因表达。不同的细菌在其遗传程序中进行大的改变时需要进行反式翻译，