摘要
Argonaute蛋白广泛存在于真核生物与原核生物中,可在非编码小RNA或DNA的引导下,对完全匹配或部分匹配的靶标进行切割、翻译抑制或染色体修饰。本研究利用生物信息学对127种卵菌与真菌的基因组进行分析,旨在了解各个物种中AGO家族基因的数量、蛋白结构域、进化关系及转录模式等。结果发现,大部分卵菌与真菌的基因组中(51%)含有2个AGO基因,而疫霉菌和壶菌等平均含有4个以上。卵菌与真菌的AGO基因在进化上相互独立,多拷贝AGO基因可能是通过基因复制形成;大部分AGO基因具有6个可预测的功能域(即:N端、Linker 1、PAZ、Linker 2、MID和PIWI),并且在PAZ和PIWI功能域上,与核酸5’和3’端结合及与催化活性相关的氨基酸位点整体相对保守,仅个别位点存在一定的差异。侵染大豆过程中,大豆疫霉和终极腐霉的两对同源AGO基因具有保守的表达模式,且基因表达水平相对较高,可能具有相似的生物学功能。上述结果将为深入解析AGO介导的RNA干扰机制及生物学功能奠定基础。
Argonaute(AGO)proteins are conserved in eukaryotes and prokaryotes,which were guided by non-coding small RNA or DNA for degradation,translation repression,or chromatin modification of the completely or partially matching targets.In this study,we analyzed AGO family genes in 127 oomycete and fungal species via bioinformatic approaches on amounts of AGO genes,functional domains,phylogenetic relationships and transcriptional patterns.We found that 51%of the analyzed species contained two AGO genes,while some species,such as those in Phytophthora genus and Chytridiomycetes class,contained at least four AGO genes.Phylogeny of AGO genes was distinct between oomycetes and fungi and the multiple copies of AGO genes might be the results of gene duplication before or after specie evolution.Nearly all AGO proteins had 6 predicted domains,i.e.N,Linker 1,PAZ,Linker 2,MID,and PIWI.Conservation of residues corresponding to the 5’and 3’nucleic acid binding sites and catalytic sites in PAZ and PIWI domains were observed in oomycete and fungi,despite of few varied individual loci.Similar transcription patterns and high levels during the infection implied conserved functions of the two paralleling orthologous AGO genes from Phytophthora sojae and Pythium ultimum.The results will provide fundamental understanding for the AGO proteins on RNA interference mechanisms and biological functions.
作者
李喻菲
林龙
宣铭润
冯慧
叶文武
王源超
LI Yu?fei;LIN Long;XUAN Ming?run;FENG Hui;YE Wen?wu;WANG Yuan?chao(College of Plant Protection,Nanjing Agricultural University,Nanjing 210095,China)
出处
《植物病理学报》
CAS
CSCD
北大核心
2020年第1期60-67,共8页
Acta Phytopathologica Sinica
基金
国家自然科学基金面上项目(31772140)
国家自然科学基金创新群体项目(31721004).
作者简介
通讯作者:叶文武,副教授,主要从事植物-病原菌互作的基因组学研究,Tel:025-84399621,E-mail:yeww@njau.edu.cn;第一作者:李喻菲,女,硕士研究生,主要从事植物-病原物互作中的小RNA研究,E-mail:2016102029@njau.edu.cn.
