由Robert Coutts博士領導的研究人員發現了一種全新類型的真菌病毒。這項研究發表在《美國國家科學院院刊》(PNAS)上。

　　這種病毒感染煙曲黴菌型真菌，該細菌能引起人類患曲黴病。這種真菌靶向感染肺器官，並且是免疫力低下的個體發病率和死亡率的主要原因。

　　這種真菌病毒稱為煙曲黴菌-1(AfuTmV-1)，是由四條雙鏈核糖核酸(dsRNA)和具有獨特序列特征的基因染色體組組成。與幾乎所有病毒都不同的是它的遺傳信息不是用殼體包裹而是包被在病毒編碼的蛋白質中，這些核糖核蛋白結構通過原子力顯微鏡首次具體的顯現出來。

　　最重要的是，在沒有蛋白質衣殼的情況下，AfuTmV-1染色體組就其本身而言可以感染真菌，這個特性以前在dsRNA中從未有過，包括病毒在內。因此，染色體組可能因通過基因工程直接導入到真菌中而發生改變。

　　希望AfuTmV-1會被用於開發成一種沉默載體，它是一種可以切斷真菌基因的工具，該載體可幫助研究分析煙曲黴菌中的什麼物質會導致人類患曲黴病。

　　AfuTmV-1是新型真菌病毒家族的原型，但它並不是唯一的，因為相似的真菌病毒也被發現在不同的真菌屬中，表明了在未來真菌界中用於構建通用沉默載體的這些dsRNA要素具有的潛在效用。

　　doi:10.1073/pnas.1419225112

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A novel mycovirus from Aspergillus fumigatus contains four unique dsRNAs as its genome and is infectious as dsRNA

　　.Lakkhana Kanhayuwaa,1, Ioly Kotta-Loizoua,1, Selin zkana,2, A. Patrick Gunningb, and Robert H. A. Couttsa,3,4

　　We reportthediscovery and characterization of a double-stranded RNA (dsRNA) mycovirus isolated from the human pathogenic fungus Aspergillus fumigatus, Aspergillus fumigatus tetramycovirus-1 (AfuTmV-1), which reveals several unique features not found previously in positive-strand RNAviruses, including the fact that it represents the first dsRNA (to our knowledge) that is not only infectious as a purified entity but also as a naked dsRNA. The AfuTmV-1 genome consists of four capped dsRNAs, the largest of which encodes an RNA-dependent RNApolymerase(RdRP) containing a unique GDNQ motif normally characteristic of negative-strand RNA viruses. The third largest dsRNA encodes an S-adenosyl methionine–dependent methyltransferase capping enzyme and the smallest dsRNA a P-A-S–rich protein that apparently coats but does not encapsidate the viral genome as visualized by atomic force microscopy. A combination of a capping enzyme with a picorna-like RdRP in the AfuTmV-1 genome is a striking case of chimerism and the first example (to our knowledge) of such a phenomenon. AfuTmV-1 appears to be intermediate between dsRNA and positive-strand ssRNA viruses, as well as between encapsidated and capsidless RNA viruses.