Abstract
Soybean mosaic virus (SMV), a member of the genus Potyvirus, is a prevalent and devastating viral pathogen in soybean-growing regions worldwide. Potyvirus-encoded P3 protein is reported to participate in virus replication, movements, and pathogenesis. This study provides evidence that the soybean (Glycine max) endo-1,3-beta-glucanase protein (designated as GmGLU) interacts with SMV-P3 by using a yeast two-hybrid system to screen a soybean cDNA library. A bimolecular fluorescence complementation assay further confirmed the interaction, which occurred on the cytomembrane in Nicotiana benthamiana cells. Subcellular localization experiment indicated that GmGLU localized in cytomembrane and could co-localized at PD with PD marker. The transient expression of GmGLU promoted the coupling of Turnip mosaic virus replication and cell-to-cell movement in N. benthamiana. Meanwhile, qRT-PCR experiment demonstrated that the expression of GmGLU which involved in callose regulation increased under SMV infection. Under SMV infection, callose deposition at PD was observed obviously by staining with aniline blue, which raise a physical barrier restricting cell-to-cell movement of SMV. When overexpression the GmGLU into the leaves under SMV infection, the callose induced by SMV was degraded. Coexpression the GmGLU and SMV in soybean leaves, callose was not found, whereas a large amount of callose deposition on soybean leaves which were only under SMV infection. The results show that GmGLU can degrade the callose induced by SMV infection and indicate that GmGLU may be an essential host factor involvement in potyvirus infection.
Highlights
Soybean mosaic virus (SMV), a member of the family Potyviridae, is the causative agent of one of the most well-known viral diseases affecting soybean (Kim et al, 2016)
In a membrane yeast two-hybrid system (mY2HS) analysis using the SMV-P3 protein as bait and a soybean cDNA library as prey, one candidate gene was encoding SMV-P3 was inserted into pBT3-STE and the complete cDNA of soybean soybean endo-1 (GmGLU) (Accession Number: AY461847.1) was inserted into pPR3-gateway
At 36 h post-SMV inoculation, we found that the fluorescence formed by callose at the inoculation point disappeared following the transfection of GmGLU (Figures 5E,F), while there was considerable callose deposition on soybean leaves which were only infected with SMV (Figures 5D,F)
Summary
Soybean mosaic virus (SMV), a member of the family Potyviridae, is the causative agent of one of the most well-known viral diseases affecting soybean (Kim et al, 2016). Some studies further revealed that the P3 cistron may function as a virulence determinant for the SMV elicitors of Rsv1-mediated resistance (Hajimorad et al, 2006, 2008, 2011; Chowda-Reddy et al, 2010; Wen et al, 2011, 2012; Wang et al, 2014). Previous studies have revealed that the Tobacco etch virus P3 protein is localized in the ER membrane and forms punctate inclusions in association with the Golgi apparatus (Cui et al, 2010). The P3 punctate structure was found to traffic along the actin filaments and co-localize with the 6 kDa peptide-containing replication vesicles (Cui et al, 2010). We speculate that P3 may act as a bridge between virus replication and movement
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
