AN AMINO ACID SUBSTITUTION OF THE COAT PROTEIN OF PLUM POX VIRUS ALTERS ITS MOBILITY ON SDS-PAGE
夏目, 祐樹NATSUME, Yuki
562015-03-24 , 法政大学大学院理工学・工学研究科
Plum pox virus (genus Potyvirus, family Potyviridae, PPV) is one of the most devastating plant viruses in the world. In 2009, PPV was first detected in Japanese apricot trees in Tokyo. We obtained four sample trees, Ak19-8, Ak19-9, Ak19-11, and Ak19-14, from a single field in Akiruno city, Tokyo. The symptoms of these trees were almost the same, however, by a Western-blot analysis, viral coat protein (CP) of Ak19-8 is apparently smaller than those of other three trees. We analyzed the sequences of their genomic RNAs and compared the deduced amino acid sequences of the CPs. We found difference in 66th amino acids, which was glycine in Ak19-8, while they were glutamic acid in Ak19-9, 11 and 14. This position is known to affect the manner of the modification of CP. It is also reported that CP was modified by O-linked N-acetylglucosamine (O-GlcNAc), which was suggested to work for host fitness. We separated the CPs of purified Ak19-8 and Ak19-14 particles by SDS-PAGE, and the CP bands were subjected to the MALDI-TOF MS analysis. The CP of Ak19-14 has two peaks correspond to the peptide of 40-93 amino acids carrying two and five O-GlcNAc, suggesting that the CP of the Japanese PPV are also modified by O-GlcNAc, and the manner of the modification could be different according to the 66th amino acid.