依赖于5′端非编码区高级结构的真核生物mRNA翻译调控

Translational Control of Eukaryotic Gene Depending on Higher Structures in 5′Untranslated Regions

翻译水平的调控是真核基因表达调控的重要环节.近年来的研究表明,许多真核基因的翻译依赖于RNA5′端非编码区的结构元件.一些小结构元件,如铁离子反应元件,具有1个茎环结构,由铁离子介导控制转铁蛋白的翻译.核糖开关通过结合特定代谢分子在2种结构状态下切换,调控可变剪接和翻译起始.另1个高度结构化的mRNA元件是内部核糖体进入位点,通过富集核糖体和起始因子促进基因的表达.本文综述了依赖于小结构元件、内部核糖体进入位点和核糖开关的真核基因翻译起始调控相应的研究成果和研究方法.对于研究的前景以及可能存在的挑战也作出阐述.

Translational regulation is a key step in eukaryotic gene expression, which is significantly dependent on the RNA structures/elements in the 5＇untranslated regions, according to recent studies. Certain small structural elements, such as iron responsive element, which is a stem-loop structure and responsible for the iron-dependent regulation of ferritin translation. The riboswitches play important roles in translation initiation and alternative splicing by switching between two mutually exclusive structures that bind specific metabolites. Another higher-order structural element, internal ribosome entry site （IRES）, can recruit ribosomes and hijack initiation factors to promote gene expression. In this review, we will give an overview in current progresses and methodologies in translational regulation research of eukaryotic gene expression,especially the roles of small structural elements, IRES and riboswitches. We will prospect the promises and challenges that may face to the researchers in this research field.