Molecular Characterization of Novel Totivirus-Like Double-Stranded RNAs from Puccinia striiformis f. sp. tritici , the Causal Agent of Wheat Stripe Rust

• Published in: Frontiers in microbiology 2017-10, Vol.8, p.1960-1960
• Main Authors: Zheng, Li, Lu, Xia, Liang, Xiaofei, Jiang, Shuchang, Zhao, Jing, Zhan, Gangming, Liu, Peng, Wu, Jianhui, Kang, Zhensheng
• Format: Article
• Language: English
• Subjects: deep sequencing; Microbiology; mycovirus; Puccinia striiformis; Totivirus; wheat stripe rust
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2017.01960

Characterization of newly isolated mycoviruses may contribute to understanding of the evolution and diversity of viruses. Here, a deep sequencing approach was used to analyze the double-stranded RNA (dsRNA) mycoviruses isolated from field-collected samples in China. Database searches showed the presence of at least four totivirus-like sequences, termed virus 1 to 4 (PsV1 to 4). All of these identified sequences contained two overlapping open reading frames (ORFs) which encode a putative coat protein (CP) and an RNA-dependent RNA polymerase (RdRp) showing similar structures to members of the genus . Each PsV contained a -1 ribosomal frameshifting region with a slippery site and a pseudoknot structure in the overlapped regions of these ORFs, indicating that the RdRp is translated as a CP-RdRp fusion. Phylogenetic analyses based on RdRp and CP suggested that these novel viruses belong to the genus in the family . The presences of these PsVs were further validated by transmission electron microscope (TEM) and RT-PCR. Taken together, our results demonstrate the presence of diverse, novel totiviruses in the field populations.