The p23 of Citrus Tristeza Virus Interacts with Host FKBP-Type Peptidyl-Prolylcis-Trans Isomerase 17-2 and Is Involved in the Intracellular Movement of the Viral Coat Protein

• Published in: Cells (Basel, Switzerland) Switzerland), 2021-04, Vol.10 (4), p.934
• Main Authors: Yang, Zuokun, Zhang, Yongle, Wang, Guoping, Wen, Shaohua, Wang, Yanxiang, Li, Liu, Xiao, Feng, Hong, Ni
• Format: Article
• Language: English
• Subjects: Capsid Proteins - metabolism; Capsids; Cell walls; Chloroplasts; Citrus - metabolism; Citrus - virology; citrus tristeza virus; Cloning; Closterovirus; Closterovirus - metabolism; Coat protein; Complementation; CP protein; Cytoplasm; Enzymes; FK506-binding protein; Gene expression; Genes; Host-Pathogen Interactions; Intracellular Space - metabolism; Localization; mRNA; Nicotiana - virology; p23; Phenotype; Plant Leaves - cytology; Plant Leaves - virology; Plant Proteins - metabolism; Plant Viral Movement Proteins - metabolism; Plasmodesmata; Protein Binding; Protein Transport; protein-protein interaction; Proteins; RNA-mediated interference; Subcellular Fractions - metabolism; Tacrolimus; Tacrolimus-binding protein; Viruses
• ISSN: 2073-4409; 2073-4409
• DOI: 10.3390/cells10040934

is a member of the genus in the family . The p23 of citrus tristeza virus (CTV) is a multifunctional protein and RNA silencing suppressor. In this study, we identified a p23 interacting partner, FK506-binding protein (FKBP) 17-2, from (CaFKBP17-2), a susceptible host, and (NbFKBP17-2), an experimental host for CTV. The interaction of p23 with CaFKBP17-2 and NbFKBP17-2 were individually confirmed by yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Subcellular localization tests showed that the viral p23 translocated FKBP17-2 from chloroplasts to the plasmodesmata of epidermal cell of leaves. The knocked-down expression level of NbFKBP17-2 mRNA resulted in a decreased CTV titer in plants. Further, BiFC and Y2H assays showed that NbFKBP17-2 also interacted with the coat protein (CP) of CTV, and the complexes of CP/NbFKBP17-2 rapidly moved in the cytoplasm. Moreover, p23 guided the CP/NbFKBP17-2 complexes to move along the cell wall. To the best of our knowledge, this is the first report of viral proteins interacting with FKBP17-2 encoded by plants. Our results provide insights for further revealing the mechanism of the CTV CP protein movement.