Pod pepper vein yellows virus, a new recombinant polerovirus infecting Capsicum frutescens in Yunnan province, China

Abstract

Pepper vein yellows viruses (PeVYV) are phloem-restricted viruses in the genus Polerovirus, family Luteoviridae. Typical viral symptoms of PeVYV including interveinal yellowing of leaves and upward leaf curling were observed in pod pepper plants (Capsicum frutescens) growing in Wenshan city, Yunnan province, China. The complete genome sequence of a virus from a sample of these plants was determined by next-generation sequencing and RT-PCR. Pod pepper vein yellows virus (PoPeVYV) (MT188667) has a genome of 6015 nucleotides, and the characteristic genome organization of a member of the genus Polerovirus. In the 5’ half of its genome (encoding P0 to P4), PoPeVYV is most similar (93.1% nt identity) to PeVYV-3 (Pepper vein yellows virus 3) (KP326573) but diverges greatly in the 3’-part encoding P5, where it is most similar (91.7% nt identity) to tobacco vein distorting virus (TVDV, EF529624) suggesting a recombinant origin. Recombination analysis predicted a single recombination event affecting nucleotide positions 4126 to 5192 nt, with PeVYV-3 as the major parent but with the region 4126-5192 nt derived from TVDV as the minor parent. A full-length clone of PoPeVYV was constructed and shown to be infectious in C. frutescens by RT-PCR and the presence of icosahedral viral particles.

Construction of an infectious full‑length and eGFP-tagged cDNA clone of a chilli ringspot virus isolate from Yunnan province, China

“…In a previous study using Next-generation RNA-Seq sequencing (NGS) and RT-PCR we showed that ChiRSV, pepper vein yellows virus, chilli veinal mottle virus, tomato zonate spot virus and cucumber mosaic virus were prevalent in samples of pepper (Capsicum frutescens L.) plants from Wenshan city Yunnan province, China which had severe yellowing and curling symptoms [12]. ChiRSV was detected by RT-PCR in 31 of the 89 symptomatic samples.…”

“…The subsequent PCR used primers DP-ChiRSV f/DP-ChiRSV r (Supplementary Table S1) and incubation at 98°C for 3min, followed by 35 cycles of 98°C for 30s, 55°C for 30s, 68°C for 1kb/min and a nal incubation at 68°C for 10min. 5' and 3' RACE reactions were performed to obtain the complete 5'and 3' terminal sequences and three overlapping sections were ampli ed to verify the full-length sequence as described before [12]. The genome of ChiRSV-YN/Wenshan was 9653 nt long (Supplementary Figure S1A) and the sequence was deposited in GenBank with accession number: MZ269480.…”

“…The ChiRSV-YN/Wenshan isolate was obtained in 2019 from plants with severe symptoms of PeVYD (pepper vein yellows disease). This disease is associated with co-infection by several viruses but especially the phloem-limited PoPeVYV (pod pepper vein yellows virus) together with PoPeVYVaRNA (pod pepper vein yellows virus-associated RNA) [7,12]. Our infectious clone will also be a useful tool for examining whether ChiRSV can assist infection by PoPeVYV in the absence of PoPeVYVaRNA.…”

“…To examine the biological characteristics of ChiRSV-YN/Wenshan and to provide a tool for future investigations of mixed virus infection in pepper plant, a full-length infectious clone (pChiRSV) was prepared. The recombination cloning method was used to insert the complete ChiRSV cDNA sequence between the duplicated 35S promoter and hepatitis delta virus ribozyme (HDV-Rz) as described previously [12]. Then, pChiRSV was transformed into Agrobacterium tumefaciens which was then delivered to Nicotiana benthamiana plantlets by in ltration.…”