Multifaceted role of geminivirus associated betasatellite in pathogenesis

Abstract

Summary Begomoviruses have emerged as a group of plant pathogens that cause devastating diseases in a wide range of crops in tropical and subtropical regions of the world. Betasatellites, the circular single‐stranded DNA molecules with the size of almost half of that of the associated helper begomoviruses, are often essential for the production of typical disease symptoms in several virus‐host systems. Association of betasatellites with begomoviruses results in more severe symptoms in the plants and affects the yield of numerous crops leading to huge agroeconomic losses. βC1, the only protein encoded by betasatellites, plays a multifaceted role in the successful establishment of infection. This protein counteracts the innate defence mechanisms of the host, like RNA silencing, ubiquitin‐proteasome system and defence responsive hormones. In the last two decades, the molecular aspect of betasatellite pathogenesis has attracted much attention from the researchers worldwide, and reports have shown that βC1 protein aggravates the helper begomovirus disease complex by modulating specific host factors. This review discusses the molecular aspects of the pathogenesis of betasatellites, including various βC1‐host factor interactions and their effects on the suppression of defence responses of the plants.

Analysis of Pathogenicity and Virulence Factors of Ageratum leaf curl Sichuan virus

“…Previous research also showed that the C1 protein of Mulberry mosaic dwarf-associated virus can cause similar symptoms in host plants (Yang et al, 2018). Furthermore, Wezel et al found that PVX-driven expression of C1+C4 causes local and systemic necrosis in N. benthamiana, and that C4 is necessary for systemic necrosis induction (using a C1 mC4 construct) (Wezel et al, 2002). However, this phenomenon was not found in our experiments.…”

Begomovirus-Associated Betasatellite Virulence Factor βC1 Attenuates Tobacco Defense to Whiteflies via Interacting With Plant SKP1

“…Betasatellites associated to begomoviruses have been shown to be determinants in virus disease symptom induction, virus movement, repression of plant defense, and other aspects of viral pathogenesis (Zhou, 2013). bC1 interacts with a number of host proteins to affect phytohormone, methylation, ubiquitin, and photosynthesis pathways in plants (Gnanasekaran et al, 2019; Values are mean ± SEM, n = 30. Student's t test was used for significant difference analysis (*P < 0.05).…”

Molecular Insights into Host and Vector Manipulation by Plant Viruses

“…Most monopartite begomoviruses associate with betasatellites that enhance accumulation of the helper virus and are essential for induction of typical disease symptoms. Betasatellites share no significant sequence similarity with their helper virus, but depend on them for replication, movement in plants and insect transmission by trans-encapsidation [54]. They encode a single protein (βC1) that determines pathogenicity and symptom phenotype.…”

“…They encode a single protein (βC1) that determines pathogenicity and symptom phenotype. Numerous studies have shown that βC1 is a key element targeted by plant defence mechanisms and able to repress and manipulate plant defences [54,55]. For instance, βC1 can reverse RNA silencing and interfere with two major protein degradation processes, the ubiquitin-proteasome system and the autophagy pathway [51].…”