Self-interaction of Citrus tristeza virus p33 protein via N-terminal helix

• Published in: Virus research 2017-04, Vol.233, p.29-34
• Main Authors: Kang, Sung-Hwan, Dao, Thi Nguyet Minh, Kim, Ok-Kyung, Folimonova, Svetlana Y.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Binding Sites; Citrus - virology; Citrus tristeza virus; Cloning, Molecular; Closterovirus - genetics; Closterovirus - metabolism; Closterovirus - pathogenicity; Gene Expression; Genetic Vectors - chemistry; Genetic Vectors - metabolism; Genome, Viral; Host Specificity; Membrane Proteins - chemistry; Membrane Proteins - genetics; Membrane Proteins - metabolism; Models, Molecular; Nicotiana - genetics; Nicotiana - metabolism; Plant Diseases - virology; Plant virus; Protein Binding; Protein Conformation, alpha-Helical; Protein Interaction Domains and Motifs; Protein–protein interaction; Recombinant Proteins - chemistry; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Sequence Alignment; Sequence Homology, Amino Acid; Viral Proteins - chemistry; Viral Proteins - genetics; Viral Proteins - metabolism
• ISSN: 0168-1702; 1872-7492
• DOI: 10.1016/j.virusres.2017.03.008

•The p33 protein of Citrus tristeza virus self-interacts.•The N-terminal helix of p33 is required and sufficient for the self-interaction.•The helix appears to be exposed to facilitate the intermolecular interaction. Citrus tristeza virus (CTV), the most economically important viral pathogen of citrus, encodes a unique protein, p33. CTV p33 shows no similarity with other known proteins, yet plays an important role in viral pathogenesis: it extends the virus host range and mediates virus ability to exclude superinfection by other variants of the virus. Previously we demonstrated that p33 is an integral membrane protein and appears to share characteristics of viral movement proteins. In this study, we show that the p33 protein self-interacts in vitro and in vivo using co-immunoprecipitation, yeast two hybrid, and bimolecular fluorescence complementation assays. Furthermore, a helix located at the N-terminus of the protein is required and sufficient for the protein self-interaction.