同义密码子使用偏嗜性对mRNA半衰期及翻译调控的影响

Effects of synonymous codon usage bias on mRNA half-life and translational regulation

摘要:

随着基因组学和转录组学在不同生物体遗传和细胞生物学领域的广泛应用，同义密码子使用的偏嗜性逐渐被接受，并且在研究生物进化与生物表型之间的深层联系时，同义密码子使用模式受到相关领域研究人员的重视。信使RNA (messenger RNA,mRNA)最终表达出具有正常生物活性的蛋白产物是生命活动的重要环节。被称为“第二遗传密码”的同义密码子使用模式，可以通过精微调控翻译选择压力等分子机制，从转录调控、翻译调控及代谢活动等水平表达其承载的遗传信息。研究表明，mRNA半衰期的长短对mRNA活性以及转录和翻译过程有显著的影响。因此，系统地归纳同义密码子使用模式在基因转录、翻译调控及翻译后修饰等生命活动中所扮演的角色，将有助于全方位审视生物体如何巧妙利用密码子使用模式所产生的遗传效应来精准合成不同种类蛋白质，并以此保障生长或分化的特定基因表达程序顺利执行、维持正常的生命周期。

Abstract:

With the widespread application of genomics and transcriptomics in the genetics and cell biology of different species,synonymous codon usage bias has been gradually accepted and used to study the deep connection between biological evolution and biological phenotypes.It is an important part of the life activities that mRNA is expressed into proteins with normal biological activities.The synonymous codon usage patterns,which were named as ‘the second genetic codon’,can express genetic information carried by themselves at the levels of transcriptional regulations,translational regulations and metabolic activities through molecular mechanisms such as fine-tune translation selection.Some studies have shown that the length of mRNA half-life has significant impacts on mRNA activity and the process of transcription and translation.This review summarized the roles of synonymous codon usage patterns in transcription,translational regulation and post-translational modification,with the aim to better understand how organisms skillfully utilize the genetic effects caused by codon usage patterns to accurately synthesize different types of proteins,so as to ensure the growth or differentiation of the specific gene expression procedures to carry out smoothly and maintain the normal life cycle.