Identification and Characterization of a Host Reversibly Glycosylated Peptide that Interacts with the Tomato leaf curl virus V1 Protein

• Published in: Plant molecular biology Vol. 61; no. 1-2; pp. 297 - 310
• Main Authors: Selth, L.A, Dogra, S.C, Rasheed, M.S, Randles, J.W, Rezaian, M.A
• Format: Journal Article
• Language: English
• Published: Netherlands Springer Nature B.V 01-05-2006
• Subjects: Begomovirus; binding proteins; cDNA libraries; DNA, Viral - metabolism; Geminiviridae - genetics; Geminiviridae - metabolism; Geminiviridae - pathogenicity; Gene Library; Glycosylation; Green Fluorescent Proteins - analysis; Infections; Leaves; Lycopersicon esculentum - metabolism; Lycopersicon esculentum - virology; Onions - genetics; Peptides; Phylogeny; Plant diseases; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Proteins - physiology; Plants, Genetically Modified - cytology; Plants, Genetically Modified - metabolism; protein binding; protein-protein interactions; Proteins; Recombinant Fusion Proteins - analysis; Saccharides; Sequence Analysis, Protein; Solanum lycopersicum var. lycopersicum; Tomato leaf curl virus; Tomatoes; Two-Hybrid System Techniques; Viral infections; viral proteins; Viral Proteins - metabolism; Viral Proteins - physiology; Yeasts
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/s11103-006-0028-5

Monopartite geminiviruses of the genus Begomovirus have two virion-sense genes, V1 and V2. V2 encodes the viral coat protein, but the function of V1 is largely unknown, although some studies suggest that it may play a role in cell-to-cell movement. Yeast two-hybrid technology was used to identify possible host binding partners of V1 from Tomato leaf curl virus (TLCV) to better understand its function. A protein closely related to a family of plant reversibly glycosylated peptides, designated SlUPTG1, was found to interact with V1 in yeast and in vitro. SlUPTG1 may function endogenously in the synthesis of cell wall polysaccharides, since a bacterially expressed form of the protein acted as an autocatalytic glycosyltransferase in epsilon vitro, a SlUPTG1:GFP fusion protein localized to the cell wall, and expression of SlUPTG1 appeared to be highest in actively dividing tissues. However, expression of SlUPTG1 in a transient TLCV replication assay increased the accumulation of viral DNA, suggesting that this host factor also plays a role in viral infection. Together, these data provide new insight into the role of V1 in TLCV infection and reveal another host pathway which geminiviruses may manipulate to achieve an efficient infection.