Biological and Genetic Characterization of Pod Pepper Vein Yellows Virus-Associated RNA From Capsicum frutescens in Wenshan, China

Abstract

Tombusvirus-like associated RNAs (tlaRNAs) are positive-sense single-stranded RNAs found in plants co-infected with some viruses of the genus Polerovirus. Pod pepper vein yellows virus (PoPeVYV) was recently reported as a new recombinant polerovirus causing interveinal yellowing, stunting, and leaf rolling in Capsicum frutescens plants at Wenshan city, Yunnan province, China. The complete genome sequence of its associated RNA has now been determined by next-generation sequencing and reverse transcription (RT) polymerase chain reaction (PCR). PoPeVYV-associated RNA (PoPeVYVaRNA) (GenBank Accession No. MW323470) has 2970 nucleotides and is closely related to other group II tlaRNAs, particularly tobacco bushy top disease-associated RNA (TBTDaRNA, GenBank Accession No. EF529625). In infection experiments on Nicotiana benthamiana and C. frutescens plants, synergism between PoPeVYVaRNA and PoPeVYV was demonstrated, leading to severe interveinal yellowing of leaves and stunting of plants. The results provide further information on the genetic and biological properties of the various agents associated with pepper vein yellows disease (PeVYD).

Synergism Among the Four Tobacco Bushy Top Disease Casual Agents in Symptom Induction and Aphid Transmission

“…Several tlaRNAs have been reported to enhance polerovirus accumulations in infected plants and to intensify disease symptoms ( Sanger et al, 1994 ; Mo et al, 2015 ; Yoshida, 2020 ; Peng et al, 2021 ). Through sequencing and phylogenetic analyses, we have determined that TVDVaRNA-YK is evolutionary closely related to TBTDaRNA-YK.…”

Diversity of polerovirus‐associatedRNAsin the virome of wild and cultivated carrots

“…Satellite tlaRNAs are single‐stranded, positive‐sense RNAs of about 3 kb harbouring two open reading frames (ORFs), ORF1a and ORF1b. ORF1a encodes a protein of about 30 kDa and ORF1b is expressed by the readthrough of the ORF1a termination codon, resulting in a fusion protein encoding the satellite RNA‐dependent RNA polymerase (RdRp) (Campbell et al, 2020; Peng et al, 2021). There are few studies addressing the specificity of the association between satellites and their helper virus (Kurath et al, 1993; Oncino et al, 1995).…”

“…There are few studies addressing the specificity of the association between satellites and their helper virus (Kurath et al, 1993; Oncino et al, 1995). This may be due to the fact that such disease complexes have been largely analysed under controlled conditions, focusing on a specific virus–satellite association in a single host species (Mo et al, 2011; Peng et al, 2021), leading to a consequential knowledge gap on such complexes in more natural infection conditions. However, the fact that isolates of beet western yellows virus‐associated RNA (BWYVaRNA) and turnip yellows virus‐associated RNA (TuYVaRNA) show over 93% identity over their entire genome and the recent report of the partial sequence of a potato leafroll virus‐associated RNA (MF133518; Campbell et al, 2020) showing 99.5% nucleotide identity with carrot red leaf virus‐associated RNA (CtRLVaRNA) suggests some level of promiscuous associations involving tlaRNAs.…”

“…In contrast, BWYVaRNA, first described as an autonomously replicating subviral RNA (Chin et al, 1993), has been shown to stimulate the accumulation of its helper virus, beet western yellows virus (BWYV, genus Polerovirus; Sanger et al, 1994). Similarly, the recently described pod pepper vein yellows virus-associated RNA (PoPeVYVaRNA) has been shown to stimulate the accumulation of its helper virus, leading to increased virulence (Peng et al, 2021). Other examples of such tlaRNAs are tobacco bushy top disease-associated RNA (TBTDaRNA), which is involved in the tobacco bushy top disease complex (Mo et al, 2011) and arracacha latent virus E-associated RNA (ALVEaRNA), which was recently identified in the virome of Arracacia xanthorrhiza, characterized by high-throughput sequencing (HTS; partial genomic sequences MF136436 and MF073199).…”

A plant-infecting subviral RNA associated with poleroviruses produces a subgenomic RNA which resists exonuclease XRN1 in vitro

“…Viral satellites and subviral entities have been noted to exert an influence on the ecological and evolutionary dynamics of the viruses they associate with, with effects ranging from synergism to antagonism ( Moreno and López-Moya, 2020 ). In the case of tlaRNAs, including the most well-studied, designated ST9, increases in symptom severity have been observed in co-infections with poleroviruses in some host plants ( Peng et al, 2021 ; Sanger et al, 1994 ; Falk and Duffus, 1984 ). Interestingly, increased symptom severity upon co-infection of tlaRNAs and poleroviruses has been observed to be host-dependent (unpublished observations).…”