Indian Journal of Virology

Narcissus tazetta cv. Paperwhite is an important ornamental for the floriculture industry. Narcissus is susceptible to three members of genus Potyvirus, namely Narcissus yellow stripe virus, Narcissus late season yellows virus and Narcissus degeneration virus, apart from Narcissus latent virus (genus Macluravirus, family Potyviridae). A disease characterized by severe mosaic and light green to yellow leaf stripes, was observed on Narcissus in an experimental plot at the National Botanical Research Institute, Lucknow. Affected plants also showed extreme reduction in their growth, and loss of yield and bloom quality. For over expression of coat protein (CP) gene in E. coli, the CP nucleotide sequence submitted by us (GenBank accession number DQ991145) was used to design CP_for and CP_rev primers. PCR using CP_for/CP_rev, yielded a DNA fragment of ca. 783 bp which was ligated in the pET 28b expression vector (Novagen), and E. coli BL-21 RIL DE3 (Stratagene) cells were transformed. The BL-21 cells containing recombinant plasmids were confirmed by restriction digestion and PCR amplification of CP gene. The conditions for optimum expression of CP were standardized against temperature and time of incubation. The protein expression was confirmed by SDS PAGE and western blotting. The expressed coat protein could be used for raising antibodies after its purification.