The host Pex19p plays a role in peroxisomal localization of tombusvirus replication proteins

• Published in: Virology (New York, N.Y.) Vol. 379; no. 2; pp. 294 - 305
• Main Authors: Pathak, Kunj B, Sasvari, Zsuzsanna, Nagy, Peter D
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 30.09.2008
• Subjects: Base Sequence; Cross-Linking Reagents; DNA Primers - genetics; DNA, Fungal - genetics; Dominant negative; Formaldehyde; Host-Pathogen Interactions; Host–virus interaction; Infectious Disease; Intracellular Membranes - metabolism; Intracellular Membranes - virology; Membrane Proteins - genetics; Membrane Proteins - isolation & purification; Membrane Proteins - metabolism; mitochondria; Mitochondria - metabolism; Mitochondria - virology; Models, Biological; Peroxisome; peroxisomes; Peroxisomes - metabolism; Peroxisomes - virology; plant proteins; plant viruses; Protein Binding; protein-protein interactions; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - isolation & purification; Recombinant Fusion Proteins - metabolism; Replication; RNA Replicase - metabolism; RNA virus; RNA, Viral - genetics; RNA, Viral - metabolism; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae - virology; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - isolation & purification; Saccharomyces cerevisiae Proteins - metabolism; Tomato bushy stunt virus; Tombusvirus; Tombusvirus - genetics; Tombusvirus - pathogenicity; Tombusvirus - physiology; Tombusvirus p33 replication protein; viral proteins; Viral Proteins - isolation & purification; Viral Proteins - physiology; Virus Replication; Yeast; Tombusvirus; Yeast; RNA virus; Tomato bushy stunt virus; Peroxisome; Host–virus interaction; Replication; Dominant negative
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/j.virol.2008.06.044

Abstract Replication of Tomato bushy stunt virus (TBSV) RNA takes place on the cytosolic membrane surface of peroxisomes in plants and in yeast, a model host. To identify the host proteins involved in assisting the peroxisomal localization of the tombusvirus p33 replication protein, we tested if p33 could bind directly to yeast proteins involved in peroxisomal transport in vitro. This work has led to the demonstration of Pex19p–p33 interaction via pull-down and co-purification experiments. Pex19p was also detected in the tombusvirus replicase after protein cross-linking, suggesting that Pex19p transiently binds to the replicase as could be expected from a transporter. To validate the importance of Pex19p–p33 interaction in TBSV replication in yeast, we re-targeted Pex19p to the mitochondria, which resulted in the re-distribution of a large fraction of p33 to the mitochondria. The expression of the mitochondrial-targeted Pex19p inhibited TBSV RNA accumulation by 2–4-fold in vivo and reduced the in vitro activity of the tombusvirus replicase by 80%. These data support the model that Pex19p is a cellular transporter for localization of p33 replication protein to the host peroxisomal membranes.