Identification and complete genome sequence of a new cheravirus discovered in grapevine.

Abstract

High-throughput sequencing (HTS) was applied to identify viruses present in grapevine samples collected in Ningxia, China, that exhibited obvious symptoms of viral disease. A putative novel cheravirus was found through the analysis of sequencing data, and its presence was confirmed by RT-PCR in a Cabernet Sauvignon sample with vein yellowing. The complete genome sequence of this virus was determined by Sanger sequencing of overlapping RT-PCR products and the rapid amplification of cDNA ends (RACE) method. The genome of the putative virus comprises two RNA segments 7,395 and 3,645 nucleotides in length, excluding their poly-A tails. The new virus was tentatively named "grapevine cheravirus" (GCheV). The Pro-Pol region of RNA1 and the CP region of RNA2 of GCheV shared the highest amino acid sequence identity, reaching 72.0% and 48.9%, respectively, with the corresponding sequences of Corymbium villosum cheravirus (CvCV). Phylogenetic analysis revealed that GCheV clustered with CvCV in the genus Cheravirus. These results suggest that GCheV is a new member of that genus. To the best of our knowledge, this is the first report of a virus belonging to the genus Cheravirus in grapevines.