植物基因组上游开放阅读框的挖掘方法及其翻译调控  

Mining Method of the Upstream Open Reading Frames and Their Translational Regulation in the Plant Genomes

作　　者：王庭璋[1] 胡望雄[1] 徐建红[1] 薛庆中[1] 

机构地区：[1]浙江大学农业与生物技术学院,杭州310058

出　　处：《中国农业科学》2013年第16期3314-3323,共10页Scientia Agricultura Sinica

基　　金：国家重点基础研究发展计划("973"计划)项目(2010CB126205);国家自然科学基金项目(31171165)

摘　　要：基因组中约有20%的基因具有上游开放阅读框(upstream open reading frame,uORF),它位于成熟mRNA 5'端非编码区(5'-UTR)。本文简介了uORF同源群的挖掘方法、分类和进化,以及调控下游mORF翻译的研究进展。植物(拟南芥和水稻等)和昆虫(果蝇等)基因组中普遍存在保守肽uORFs,并且在序列多样性方面有相似之处。但它们在平均长度、基因组聚类、与甲基转移酶的关联性上有所不同。植物uORF的长度通常短于昆虫uORF。借助拟南芥和水稻全长cDNA序列比较,不同的uORF同源群对其下游如转录因子,信号转导因子、发育信号分子和翻译起始因子eIF5等编码基因的mORF具有调控功能。对于真核生物基因组中包含CHCH域的uORF进行贝叶斯系统发育分析,结果表明,同源群8-like分属5个物种(绿藻、节肢动物、线虫、无脊椎动物和真菌)。在真核生物生长、发育和生理过程中,uORF通常作为反式因子对mORF表达起调节器作用,例如,在植物蔗糖、多胺、磷脂酰胆碱,以及甲基转移酶反应中,相当大比例的uORF参与介导mORF的翻译调控。Approximately 20% of plant genes have small upstream open reading frame（uORF）,which are located in the 5’ UTR of a mature mRNA.The mining methods,classification and evolution of the uORF homologous groups,and research progress of their translation regulation to downstream mORF were briefly introduced.Conserved peptide uORF（uORF） are ubiquitous in plants（Arabidopsis and rice） and insects（fruit fly） genomes,and they have similar diversity of sequences,but differ in their average length,genome clustering,and their preferential association with methyltransferases.Plants usually have shorter uORF than that of insects.Comparative analysis of the full-length cDNA sequences between Arabidopsis and rice showed that homology groups of uORF can play the regulatory functions on the downstream mORF,such as transcription factors,signal transduction factors,developmental signal molecules,and translation initiation factor eIF5.The Bayesian phylogenetic analysis of the uORF with the CHCH domain in the eukaryotic genomes showed that the homologous group 8-like could be divided into five branches of taxa（green algae,arthropods,nematodes,invertebrates and fungi）.uORF families could act as trans factors to regulate the expression of major ORF during the growth,development,and physiology in the eukaryotes.Quite large ratio of uORF can regulate the translation of mORF in response to the concentrations of polyamine,sucrose,phosphatidyl choline,and methyl transferase in plant genomes.

关 键 词：上游开放阅读框 翻译调控 进化 转录因子 转录物 

分 类 号：Q943.2[生物学—植物学]