Accumulation kinetics of CMV RNA 3-encoded proteins and subcellular localization of the 3a protein in infected and transgenic tobacco plants

• Published in: Archives of virology Vol. 141; no. 6; pp. 987 - 999
• Main Authors: Vaquero, C, Sanz, A.I, Serra, M.T, Garcia-Luque, I
• Format: Journal Article
• Language: English
• Published: Wien Springer 01-01-1996; New York, NY
• Subjects: Base Sequence; Biological and medical sciences; Capsid - metabolism; coat proteins; Cucumber mosaic virus; Cucumovirus - genetics; Cucumovirus - metabolism; DNA, Viral; electron microscopy; Escherichia coli; Fundamental and applied biological sciences. Psychology; gene expression; gold; immunogold localization; Immunohistochemistry; Kinetics; Molecular Sequence Data; molecular weight; Nicotiana; Nicotiana - virology; nuclei; nucleotide sequences; Phytopathology. Animal pests. Plant and forest protection; Plant Viral Movement Proteins; Plant viruses and viroids; Plants, Genetically Modified; Plants, Toxic; RNA, Viral - genetics; strain differences; Subcellular Fractions; Systematics. Structure, properties and multiplication. Genetics; viral proteins; Viral Proteins - genetics; Viral Proteins - metabolism; viral regulatory proteins; Plant pathogen; Virus replication cycle; Nicotiana tabacum; Host virus relation; Viral movement protein; Accumulation; Virus; Dicotyledones; Cucumber mosaic virus; Angiospermae; Bromoviridae; Cucumovirus; Spermatophyta; Solanaceae; Kinetics; Intracellular; Capsid
• ISSN: 0304-8608; 1432-8798
• DOI: 10.1007/BF01718603

The complete nucleotide sequence of RNA 3 of a Spanish isolate of cucumber mosaic virus (CMV-24) has been determined. The encoded putative cell-to-cell movement protein (3a protein) and the coat protein are 279 and 218 amino acids long, respectively. The 3a protein was expressed in Escherichia coli using the vector pT7-7 and was used to raise an immunoserum. We have followed the time course of accumulation of the 3a protein, in parallel to that of the coat protein, and its subcellular localization as a function of time after CMV-24 infection on tobacco plants. The maximum accumulation level of the 3a protein was reached at early stages of infection, being detected in the cytosolic and the cell wall fractions. At later stages of infection, a decline in accumulation levels of the 3a protein was observed, and the protein was essentially associated with the cell wall fractions. These data were corroborated by immunocytochemistry performed in both infected and 3a-expressing transgenic tobacco plants.