The precise regulatory role in protein synthesis by facilitating interactions with mRNA codons for various tRNA modifications is unclear. We previously reported that enhanced green fluorescent protein (GFP) reduced enhanced GFP mRNA expression in human methionine-conjugated initiator tRNA (tRNAi)/tRNA synthetase pairs under methionine-deficient conditions. Here, we investigated the effect of non-formylated methionine-conjugated Escherichia coli tRNAi on the synthesis of the protein initiation of interest (PII) in HeLa cells under intracellular L-methionine levels. We found that E. coli methionine-tRNAi counteracts human methionine-tRNAi, indicating that E. coli methionyl tRNA synthetase can induce enhanced GFP expression due to increased stability of enhanced GFP mRNA. Both complexes could support translation initiation without being employed to introduce methionine residues in the subsequent elongation steps. The results indicated that E. coli methionine-tRNAi could offset human methionine-tRNAi, and E. coli methionine-tRNAi/methionyl tRNA synthetase pairs can drive enhanced GFP mRNA expression. Unlike the human methionine-tRNAi/methionyl tRNA synthetase pairs that were used as a positive control, the non-formylated E. coli methionine-tRNAi/methionyl tRNA synthetase pairs reduced the expression of enhanced GFP mRNA, resulting in reduced HeLa cell survival. Using tRNAs functions causes of heterologous origin, such as from prokaryotes, and modified, to enhance or suppress the synthesis of specific proteins in eukaryotic organisms into the potential may possess a more prominent advantage of E. coli methionine-tRNAi as approaches that can control PII. This study provides new insights on the E. coli methionine- tRNAi/methionyl tRNA synthetase pair induced PII synthesis and the relative viability of cells could pave the way to regulate ecological/biological systems.

中文翻译：

---

大肠杆菌甲硫氨酸-tRNAi/甲硫氨酰 tRNA 合成酶对诱导感兴趣的蛋白质起始 (PII) 表达

通过促进与各种 tRNA 修饰的 mRNA 密码子的相互作用，在蛋白质合成中的精确调节作用尚不清楚。我们之前曾报道，在甲硫氨酸缺乏的条件下，增强型绿色荧光蛋白 (GFP) 降低了人甲硫氨酸偶联引发剂 tRNA (tRNAi)/tRNA 合成酶对中增强型 GFP mRNA 的表达。在这里，我们研究了非甲酰化甲硫氨酸缀合的大肠杆菌 tRNAi 对细胞内 L-甲硫氨酸水平下 HeLa 细胞中感兴趣的蛋白质起始 (PII) 合成的影响。我们发现大肠杆菌甲硫氨酸-tRNAi 抵消了人甲硫氨酸-tRNAi，表明大肠杆菌甲硫氨酰 tRNA 合成酶可由于增强型 GFP mRNA 的稳定性增加而诱导增强型 GFP 表达。两种复合物都可以支持翻译起始，而无需在随后的延伸步骤中引入甲硫氨酸残基。结果表明大肠杆菌甲硫氨酸-tRNAi 可以抵消人甲硫氨酸-tRNAi，大肠杆菌甲硫氨酸-tRNAi/甲硫氨酰 tRNA 合成酶对可以驱动增强的 GFP mRNA 表达。与用作阳性对照的人甲硫氨酸-tRNAi/甲硫氨酰 tRNA 合成酶对不同，非甲酰化大肠杆菌甲硫氨酸-tRNAi/甲硫氨酰 tRNA 合成酶对降低了增强型 GFP mRNA 的表达，导致 HeLa 细胞存活率降低。利用tRNAs的功能原因对异源来源，如来自原核生物，进行修饰，以增强或抑制真核生物体内特异蛋白质合成的潜能，大肠杆菌可能具有更突出的优势。大肠杆菌甲硫氨酸-tRNAi 作为可以控制 PII 的方法。本研究提供了关于大肠杆菌甲硫氨酸-tRNAi/甲硫氨酰 tRNA 合成酶对诱导 PII 合成的新见解，细胞的相对活力可以为调节生态/生物系统铺平道路。