Mtrf1l,也称为mitochondrial translational release factor 1-like,是线粒体翻译终止过程中的关键蛋白。在哺乳动物细胞中,线粒体翻译终止机制与细菌有所不同,其终止密码子包括UAA、UAG以及两个非标准的AGA和AGG。Mtrf1l与另一个线粒体释放因子mtRF1共同负责识别和终止这些非标准终止密码子,确保线粒体基因的正确翻译和蛋白质合成[4,5,6]。
Mtrf1l在维持线粒体功能和生物合成中发挥重要作用。研究表明,Mtrf1l的表达水平与线粒体生物合成密切相关。例如,在牛卵母细胞的发育潜能研究中,Mtrf1l的表达水平被发现与卵母细胞的发育能力相关,表明其在细胞早期发育过程中的重要性[1]。在哺乳动物细胞中,Mtrf1l的缺失导致线粒体释放因子mtRF1的GGQ基序上的谷氨酰胺甲基化缺失,这可能会影响mtRF1的功能,进而影响线粒体蛋白质的合成和细胞生长[2]。此外,在小鼠骨骼肌去神经化实验中,Mtrf1l的表达水平下降与线粒体生物合成的减少相关,提示其在维持线粒体功能和肌肉完整性中的重要作用[3]。
Mtrf1l的表达受到多种因素的调控。例如,在人类线粒体中,mtRF1的表达水平与细胞中mRNA的水平相关,表明其在翻译过程中的重要性[4]。此外,运动训练可以上调Mtrf1l的表达水平,这与运动诱导的线粒体生物合成相一致,表明Mtrf1l在运动引起的线粒体适应中发挥重要作用[7]。
综上所述,Mtrf1l是一种重要的线粒体翻译释放因子,参与调控线粒体基因的正确翻译和蛋白质合成。Mtrf1l在维持线粒体功能和生物合成中发挥重要作用,其表达受到多种因素的调控。Mtrf1l的研究有助于深入理解线粒体翻译终止机制和线粒体功能的调控机制,为相关疾病的治疗和预防提供新的思路和策略。
参考文献:
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2. Fang, Qi, Kimura, Yusuke, Shimazu, Tadahiro, Iwasaki, Shintaro, Shinkai, Yoichi. 2022. Mammalian HEMK1 methylates glutamine residue of the GGQ motif of mitochondrial release factors. In Scientific reports, 12, 4104. doi:10.1038/s41598-022-08061-y. https://pubmed.ncbi.nlm.nih.gov/35260756/
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