Work

Potential contribution of enveloped virions to long-distance movement of plant rhabdoviruses

Year: 2026

Type: article

Abstract: Current models of plant virus movement are based largely on extensive studies of nonenveloped viruses, particularly those possessing positive-sense RNA genomes. In contrast, how enveloped, negative-sense RNA plant viruses access and transit through vascular tissues remains largely unexplored. Here, we aim to address this question using two rhabdovirus–host pathosystems: rice stripe mosaic virus (RSMV) infection of rice and tomato yellow mottle-associated virus (TYMaV) infection of Nicotiana benthamiana . Immunofluorescence staining of RSMV-infected rice tissues revealed that viral antigens were predominantly localized to vascular tissues, including both xylem and phloem. Transmission electron microscopy revealed that mature enveloped virions accumulated abundantly within xylem parenchyma cells. RSMV particles were also observed in two vascular conduits: xylem vessel lumens and sieve elements. Moreover, major viral structural proteins and morphologically intact virions were detected in xylem sap. Similarly, enveloped TYMaV virions were detected in both xylem vessel elements and phloem sieve elements of infected N. benthamiana plants. Furthermore, reverse genetics analyses demonstrated that a TYMaV matrix gene deletion mutant deficient in virion morphogenesis retained wild-type levels of cell-to-cell movement but was completely defective in long-distance movement. Together, these results indicate that intact rhabdovirus virions constitute an important mobile entity for vascular long-distance trafficking, with both phloem and xylem potentially contributing to systemic movement.

Source: Frontiers in Microbiology

DOI: 10.3389/fmicb.2026.1994490