最近，胡遠(yuǎn)揚(yáng)教授研究組發(fā)現(xiàn)野田村病毒亞基因RNA3是通過(guò)內(nèi)部起始的方式從RNA1上生成，該文章已被病毒學(xué)的權(quán)威期刊J.Virol.在線發(fā)表,。該項(xiàng)研究展現(xiàn)了一種全新的野田村病毒的亞基因起始方式，并且提供了一種理解野田村病毒復(fù)制策略的新思路,。同時(shí),，關(guān)于武漢野田村病毒B2蛋白抑制RNAi的分子生物學(xué)機(jī)制的研究也已取得突破，相關(guān)論文正在投稿中,。
武漢野田村病毒是胡遠(yuǎn)揚(yáng)教授實(shí)驗(yàn)室在中國(guó)境內(nèi)發(fā)現(xiàn)的第一株野田村病毒,，這種病毒結(jié)構(gòu)簡(jiǎn)單，能夠在培養(yǎng)細(xì)胞中大量復(fù)制,，并且它能穿越物種之間屏障,，尤其是它的獨(dú)特的基因組遺傳策略使它成為研究病毒復(fù)制機(jī)制的一個(gè)很好的分子生物學(xué)模型，在生物醫(yī)學(xué)方面有很好的應(yīng)用前景,。野田村病毒基因組包括RNA1（3.1 kb）和RNA2（1.5 kb）, RNA1編碼RNA依賴的RNA聚合酶 protein A,，protein A不但復(fù)制基因組RNA，同時(shí)在病毒增殖過(guò)程中復(fù)制亞基因RNA3,；RNA2編碼衣殼蛋白前體Pro α,。RNA3對(duì)于病毒復(fù)制以及病毒完整的生活周期起到了至關(guān)重要的重要。RNA3編碼的B2蛋白,，通過(guò)抑制RNAi,，幫助病毒逃逸宿主細(xì)胞的天然免疫。另外,，RNA3能夠調(diào)節(jié)病毒基因組的復(fù)制,。（生物谷Bioon.com）
生物谷推薦原文出處：
J. Virol. doi:10.1128/JVI.02410-10
Internal initiation is responsible for the synthesis of Wuhan Nodavirus subgenomic RNA
Yang Qiu, Dawei Cai, Nan Qi, Zhaowei Wang, Xi Zhou, Jiamin Zhang, and Yuanyang Hu*
Nodaviruses are small nonenveloped spherical viruses with a bipartite genome of RNAs. In nodaviruses, subgenomic RNA3 (sgRNA3) plays a critical role in viral replication and survival, as it coordinates the replication of two viral genomic RNAs (RNA1 and RNA2) and encodes for protein B2, which is a potent RNA-silencing inhibitor. Despite of its importance, the molecular mechanism of nodaviral sgRNA3 synthesis is still poorly understood. Here, we propose that sgRNA3 of Wuhan nodavirus (WhNV) is internally initiated from a promoter on the negative template of genomic RNA1. Serial deletion and mutation analyses further revealed that the core promoter of WhNV sgRNA3 is between positions -22 nt to +6 nt of its transcription start site. Besides, a stem-loop structure of WhNV sgRNA3 was computationally predicted upstream of sgRNA3's transcription start site. Both the secondary structure and the primary sequence were determined to be required for promoter activity. Furthermore, our results show that the synthesis of WhNV sgRNA3 is counter-regulated by the replication of WhNV genomic RNA2 which encodes a viral capsid precursor protein. And this sgRNA3 synthesis is also able to trans-activate the replication of RNA2. Altogether, findings in this study indicate that there is a newly discovered internal initiation model for the synthesis of nodaviral sgRNA.
