Department of Biological Sciences, University of Idaho, Moscow, ID 83844, USA.
Center for Modeling Complex Interactions, University of Idaho, Moscow, ID 83844, USA.
Viruses. 2022 Mar 13;14(3):594. doi: 10.3390/v14030594.
Mycoviruses are widely distributed across fungi, including the yeasts of the Saccharomycotina subphylum. This manuscript reports the first double-stranded RNA (dsRNA) virus isolated from This novel virus has been named Pichia membranifaciens virus L-A (PmV-L-A) and is a member of the . PmV-L-A is 4579 bp in length, with RNA secondary structures similar to the packaging, replication, and frameshift signals of totiviruses that infect Saccharomycotina yeasts. PmV-L-A was found to be part of a monophyletic group within the I-A totiviruses, implying a shared ancestry between mycoviruses isolated from the and yeasts. Energy-minimized AlphaFold2 molecular models of the PmV-L-A Gag protein revealed structural conservation with the Gag protein of Saccharomyces cerevisiae virus L-A (ScV-L-A). The predicted tertiary structure of the PmV-L-A Pol and other homologs provided a possible mechanism for totivirus RNA replication due to structural similarities with the RNA-dependent RNA polymerases of mammalian dsRNA viruses. Insights into the structure, function, and evolution of totiviruses gained from yeasts are essential because of their emerging role in animal disease and their parallels with mammalian viruses.
真菌病毒广泛分布于真菌中，包括子囊菌亚门下的酵母。本文报道了首例从毕赤酵母属分离得到的双链 RNA（dsRNA）病毒。该新型病毒被命名为假丝酵母病毒 L-A（PmV-L-A），属于. PmV-L-A 的全长为 4579 个碱基，其 RNA 二级结构类似于感染子囊菌酵母的 totiviruses 的包装、复制和移框信号。PmV-L-A 被发现是 I-A 类 totiviruses 中的一个单系群的一部分，这表明从 和 酵母中分离到的真菌病毒具有共同的祖先。对 PmV-L-A Gag 蛋白进行能量最小化的 AlphaFold2 分子建模揭示了与酿酒酵母病毒 L-A（ScV-L-A）的 Gag 蛋白的结构保守性。PmV-L-A Pol 和其他同源物的预测三级结构提供了 totivirus RNA 复制的可能机制，因为其与哺乳动物 dsRNA 病毒的 RNA 依赖性 RNA 聚合酶具有结构相似性。由于 totiviruses 在动物疾病中的新兴作用及其与哺乳动物病毒的相似性，因此从酵母中获得的关于 totiviruses 的结构、功能和进化的见解至关重要。
