Wang Qihua, Mu Fan, Xie Jiatao, Cheng Jiasen, Fu Yanping, Jiang Daohong
State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.
Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
Front Microbiol. 2020 Mar 18;11:379. doi: 10.3389/fmicb.2020.00379. eCollection 2020.
Recently, an increasing number of ourmia-like viruses have been found in fungi; however, the features of these viruses remain unknown. Here, we report a novel ourmia-like virus isolated from . This virus, named ourmia-like virus 4 (SsOLV4), has a genome 2,982 nt in length with a G-pentamer (GGGGG) at the 5'-terminus and a C-pentamer (CCCCC) at the 3'-terminus. The SsOLV4 genome has only one large putative open reading frame (ORF) predicted with both standard codes and mitochondrial codes and encodes an RNA-dependent RNA polymerase (RdRp). SsOLV4 is closely phylogenetically related to ourmia-like virus 1, with 42% identity between the RdRp amino acid sequences. We constructed full-length cDNA of SsOLV4 and synthesized RNA using the T7 RNA polymerase. The synthesized RNA could transfect protoplasts efficiently. We further found that viral RNA could infect mycelia when mixed with PEG buffer. Our study suggests that a novel genus in family should be established for SsOLV4 and other related viruses and demonstrates that one single-stranded RNA segment encoding RdRp is sufficient for ourmia-like viruses in fungi.
最近，在真菌中发现了越来越多的类欧米亚病毒；然而，这些病毒的特征仍然未知。在此，我们报告了一种从……分离出的新型类欧米亚病毒。这种病毒名为类欧米亚病毒4（SsOLV4），基因组长度为2982个核苷酸，5'-末端有一个G-五聚体（GGGGG），3'-末端有一个C-五聚体（CCCCC）。SsOLV4基因组只有一个大的推定开放阅读框（ORF），用标准密码子和线粒体密码子预测，编码一种RNA依赖的RNA聚合酶（RdRp）。SsOLV4在系统发育上与类欧米亚病毒1密切相关，RdRp氨基酸序列之间的同一性为42%。我们构建了SsOLV4的全长cDNA，并使用T7 RNA聚合酶合成了RNA。合成的RNA可以有效地转染原生质体。我们进一步发现，病毒RNA与PEG缓冲液混合时可以感染菌丝体。我们的研究表明，应为SsOLV4和其他相关病毒在……科中建立一个新属，并证明编码RdRp的一个单链RNA片段对于真菌中的类欧米亚病毒来说是足够的。
