title: Tobacco mosaic virus coat protein and the large subunit of the host protein ribulose-1,5-biphosphate carboxylase share a common antigenic determinant.
abstract: An immunological relationship was detected between the coat protein of the common (U1) strain of tobacco mosaic virus (TMV) and the large subunit of the ubiquitous CO2-fixing host enzyme, ribulose-1,5-biphosphate carboxylase (RuBisCo). When assayed by Western immunoblotting or indirect ELISA, polyclonal antisera to TMV coat protein and to RuBisCo reacted with both antigens. In addition, a monoclonal antibody specific for the C-terminal antigenic determinant of TMV coat protein reacted with RuBisCo. Conversely, several monoclonal antibodies generated to the large subunit of RuBisCo reacted with TMV coat protein. This cross-reactivity was verified by an examination of the amino acid sequences of both proteins. A region of homology was found between the carboxy proximal portion of coat protein and the sequence 60-73 residues from the amino terminus of RuBisCo large subunit. This homology was not mirrored at the nucleic acid level because of different codon usages for the two proteins.
mesh_terms: D000595:Amino Acid Sequence; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes; D012273:Ribulose-Bisphosphate Carboxylase / Q000276:immunology*; D014027:Tobacco Mosaic Virus / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology*
chemical_list: D000939:Epitopes; D014764:Viral Proteins; D012273:Ribulose-Bisphosphate Carboxylase