Arabidopsis latent virus 1, a comovirus widely spread in Arabidopsis thaliana collections

Abstract

1) Transcriptome studies of Illumina RNA-seq datasets of different Arabidopsis thaliana natural accessions and T-DNA mutants revealed the presence of two virus-like RNA sequences which showed the typical two segmented genome characteristics of a comovirus.(2) This comovirus did not induce any visible symptoms in infected Arabidopsis plants cultivated under standard laboratory conditions. Hence it was named Arabidopsis latent virus 1 (ArLV1). Virus infectivity in Arabidopsis plants was confirmed by RT-qPCR, transmission electron microscopy and mechanical inoculation. ArLV1 can also mechanically infect Nicotiana benthamiana, causing distinct mosaic symptoms.(3) A bioinformatics investigation of Arabidopsis RNA-Seq repositories, including nearly 6500 Sequence Read Archives (SRAs) in the NCBI SRA database, revealed the presence of ArLV1 in 25% of all archived natural Arabidopsis accessions and in 8.5% of all analyzed SRAs. ArLV1 could also be detected in Arabidopsis plants collected from the wild.(4) ArLV1 is highly seed-transmissible with up to 40% incidence on the progeny derived from infected Arabidopsis plants. This has likely led to a worldwide distribution in the model plant Arabidopsis with yet unknown effects on plant performance in a substantial number of studies.

Stress & Granules : regulation of Cauliflower mosaic virus disease in Arabidopsis thaliana

“…In fact, persistent viruses of the families Partitiviridae and Endornaviridae are the most common in wild plant populations (Roossinck, 2012;Roossinck, 2015) and Lotus japonicus, a host of the Alphapartitivirus White clover cryptic virus (WCCV), was found to use the viral coat protein for its own benefit (Nakatsukasa-Akune et al, 2005), indicating that some persistent viruses have become symbiotic over time (Roossinck, 2011). A recent report found that a substantial fraction of Arabidopsis lines used in laboratories throughout the world are infected with the non-symptomatic Arabidopsis latent virus 1 (ALV), exemplifying that viruses can go undetected for a long time even in the best studied plants (Verhoeven et al, 2022). For these, as well as other more pathogenic viruses, the host tolerates the virus replication without strong triggering of defence pathways.…”

When plants are Trojan horses for viruses

“…In this issue of New Phytologist , Verhoeven et al . ( 2023 ; pp. 1146–1153) show that, as in the Aeneid story where the horse hides Odysseus and his soldiers, asymptomatic Arabidopsis thaliana (Arabidopsis) plants may harbor latent viruses with potential significant effects on the biology of the plant.…”

“… Schematic representation of the contribution of the article published in this issue of New Phytologist by Verhoeven et al . ( 2023 ; pp. 1146–1153) to the understanding of asymptomatic plant virus infections.…”