小麦黄花叶病毒 3'可变多聚腺苷酸化及其对翻译和复制的新作用。

Variable 3'polyadenylation of Wheat yellow mosaic virus and its novel effects on translation and replication.

机构信息

Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University; Shandong Province Key Laboratory of Agricultural Microbiology, No 61, Daizong Street, Shandong Province, Tai'an, 271018, People's Republic of China.

出版信息

Virol J. 2019 Feb 20;16(1):23. doi: 10.1186/s12985-019-1130-z.

DOI:10.1186/s12985-019-1130-z

PMID:30786887

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6383263/

Abstract

BACKGROUND

Polyadenylation influences many aspects of mRNA as well as viral RNA. variable polyadenylation at the 3' end have been reported in RNA viruses. It is interesting to identify the characteristic and potential role of 3' polyadenylation of Wheat yellow mosaic virus (WYMV), which has been reported to contain two genomic RNAs with 3' poly(A) tails and caused severe disease on wheat in East Asia region.

METHODS

3' RACE was used to identify sequences of the 3' end in WYMV RNAs from naturally infected wheat by WYMV. In vitro translation assay was performed to analyze effect of UTRs of WYMV with or without 3'polyadenylation on translation. In vitro replication mediated by WYMV NIb protein were performed to evaluate effect of variable polyadenylation on replication.

RESULTS

Variable polyadenylation in WYMV RNAs was identified via 3' RACE. WYMV RNAs in naturally infected wheat in China simultaneously present with regions of long, short, or no adenylation at the 3' ends. The effects of variable polyadenylation on translation and replication of WYMV RNAs were evaluated. 5'UTR and 3'UTR of WYMV RNA1 or RNA2 synergistically enhanced the translation of the firefly luciferase (Fluc) gene in in vitro WGE system, whereas additional adenylates had an oppositive effect on this enhancement on translation mediated by UTRs of WYMV. Additional adenylates remarkably inhibited the synthesis of complementary strand from viral genome RNA during the in vitro replication mediated by WYMV NIb protein.

CONCLUSIONS

3' end of WYMV RNAs present variable polyadenylation even no polyadenylation. 3' polyadenylation have opposite effect on translation mediated by UTRs of WYMV RNA1 or RNA2. 3' polyadenylation have negative effect on minus-strand synthesis of WYMV RNA in vitro. Variable polyadenylation of WYMV RNAs may provide sufficient selection on the template for translation and replication.

摘要

背景

聚腺苷酸化影响 mRNA 以及病毒 RNA 的多个方面。已有报道称，RNA 病毒在 3' 端存在可变聚腺苷酸化。有趣的是，小麦黄花叶病毒 (WYMV) 的 3' 聚腺苷酸化具有特征性和潜在作用，该病毒被报道含有两条带有 3' 多聚(A)尾巴的基因组 RNA，在东亚地区导致小麦严重病害。

方法

使用 3' RACE 从自然感染 WYMV 的小麦中鉴定 WYMV RNA 的 3' 末端序列。进行体外翻译实验，分析具有或不具有 3' 多聚腺苷酸化的 WYMV UTR 对翻译的影响。通过 WYMV NIb 蛋白进行体外复制实验，评估可变多聚腺苷酸化对复制的影响。

结果

通过 3' RACE 鉴定了 WYMV RNA 中的可变多聚腺苷酸化。中国自然感染小麦中的 WYMV RNA 同时在 3' 末端呈现长、短或无腺苷酸化区域。评估了可变多聚腺苷酸化对 WYMV RNA 翻译和复制的影响。WYMV RNA1 或 RNA2 的 5'UTR 和 3'UTR 协同增强了萤火虫荧光素酶 (Fluc) 基因在体外 WGE 系统中的翻译，而额外的腺嘌呤对 UTR 介导的翻译增强有相反的影响。在 WYMV NIb 蛋白介导的体外复制过程中，额外的腺嘌呤显著抑制了来自病毒基因组 RNA 的互补链的合成。

结论

WYMV RNA 的 3' 末端存在可变多聚腺苷酸化甚至无多聚腺苷酸化。3' 多聚腺苷酸化对 WYMV RNA1 或 RNA2 的 UTR 介导的翻译具有相反的影响。3' 多聚腺苷酸化对 WYMV RNA 体外负链合成具有负效应。WYMV RNA 的可变多聚腺苷酸化可能为翻译和复制提供了对模板的充分选择。