title: N-terminal in coat protein of Garlic virus X is indispensible for its serological detection.
abstract: Conserved coat protein region of plant viruses is often used as source of antigen for production of polyclonal antibodies for broad-based detection of closely related viruses. Antigenic region in coat protein is located either on N-terminal, and/or C-terminal or in the middle of coat protein. A study was undertaken to determine if antigenic region resides in N-terminal in Garlic virus X (GarV-X) of Allexivirus. In allexiviruses, N-terminal of coat protein region (1-57 amino acids) was highly variable. A complete coat protein of 27 kDa and a truncated protein without N-terminal (20 kDa) of GarV-X were expressed in pET expression vector and confirmed in western blotting using anti-His antisera. These expressed proteins were purified and used for antisera production. Specific and strong reaction was obtained for antisera generated against GarV-X full CP and GarV-X was detected in field-grown allium crops viz., onion, garlic, leek, and bunching onion and chives in ELISA. Antisera against GarV-X CPΔ1-61 (truncated CP) did not show reaction for GarV-X detection in immunoassay. Epitope mapping also indicated N-terminal as major antigenic determinant region with highest antigenic signal score. Our studies confirm that antigenic signals or epitopes reside in the N-terminal region of GarV-X which can be synthesized and used for production of monoclonal antibodies for specific detection purposes.
authors.affiliation: Virology Unit, Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Singh
authors.forename: K
authors.initials: K
authors.lastname: Prabha
authors.forename: Rakesh Kumar
authors.initials: RK
authors.lastname: Jain
authors.forename: V K
authors.initials: VK
authors.lastname: Baranwal
mesh_terms: D000956:Antigens, Viral / Q000032:analysis / Q000235:genetics / Q000276:immunology; D036022:Capsid Proteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology*; D018604:Epitope Mapping; D052677:Flexiviridae / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification*; D005737:Garlic / Q000821:virology; D007118:Immunoassay; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology; D019697:Onions / Q000821:virology; D010935:Plant Diseases / Q000821:virology*; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D012698:Serologic Tests
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D050505:Mutant Proteins; D012367:RNA, Viral