Association of the Tobacco mosaic virus 126kDa replication protein with a GDI protein affects host susceptibility

• Published in: Virology (New York, N.Y.) Vol. 414; no. 2; pp. 110 - 118
• Main Authors: Kramer, Sabrina R., Goregaoker, Sameer P., Culver, James N.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.06.2011
• Subjects: Guanine Nucleotide Dissociation Inhibitors - genetics; Guanine Nucleotide Dissociation Inhibitors - metabolism; Host Specificity; Nicotiana - genetics; Nicotiana - metabolism; Nicotiana - virology; Plant Diseases - genetics; Plant Diseases - virology; Plant Proteins - genetics; Plant Proteins - metabolism; Protein Binding; RNA-Dependent RNA Polymerase - genetics; RNA-Dependent RNA Polymerase - metabolism; Susceptibility; Tobacco Mosaic Virus - enzymology; Tobacco Mosaic Virus - genetics; Tobacco Mosaic Virus - physiology; Vesicle trafficking; Viral Proteins - genetics; Viral Proteins - metabolism; Virus Replication; Virus replication complex; Virus replication complex; Susceptibility; Vesicle trafficking
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/j.virol.2010.12.030

An interaction between the Tobacco mosaic virus (TMV) 126kDa replication protein and a host-encoded Rab GDP dissociation inhibitor (GDI2) was identified and investigated for its role in infection. GDI proteins are essential components of vesicle trafficking pathways. TMV infection alters the localization of GDI2 from the cytoplasm to ER-associated complexes. Partial silencing of GDI2 results in significant increases in the number of TMV infection foci observed in inoculated tissues. However, GDI2 silencing does not affect TMV accumulation at the infection site, cell-to-cell movement, or susceptibility of the host to mechanical inoculation. Furthermore, increases in the number of successful infection foci were specific to TMV and correlated with the appearance of vesicle-like rearrangements in the vacuolar membrane. Tissue infiltrations with brefeldin A, an inhibitor of vesicle trafficking, also enhanced host susceptibility to TMV. Combined these findings suggest that the 126kDa–GDI2 interaction alters vesicle trafficking to enhance the establishment of an infection.