Variations in the Cp, C2 and C3 Genes of Begomoviruses Infecting Tobacco and Honeysuckle in Japan

摘要

The variability in the CP, C2 and C3 genes monopartite begomoviruses infecting honey suckle in Japan was investigated. Samples of tobacco and honeysuckle plants showing different viral symptoms were collected from Fukuoka, Kagoshima, Kobe, Kumamoto, Nagasaki, Oita, Sapporo and Tokyo prefectures and grown in the glasshouse. The begomoviruses' CP, C2 and C3 genes were amplified and sequenced. Sequence analysis revealed that Japanese honeysuckle and tobacco begomoviruses are more closely related to oneanother than they are to other begomoviruses from outside Japan. The CP was the most conserved gene while the C2 was the most diverse. Moreover, the honeysuckle plants collected showed great symptom variability that matched the respective variabilityin the C2 gene of the infecting begomoviruses Phylogenetic analysis of the aligned sequences generated a tree with two clusters, one contained tobacco begomoviruses, while the other had honeysuckle begomoviruses. However, a few tobacco begomoviruseswhere clustered together with the honeysuckle begomoviruses and vice versa. This observation clearly shows that some tobacco begomoviruses could be infecting honeysuckle and vicevarsa. Other factors that have been implicated in symptom regulation elsewhere such as the presence or absence of DNA (3 are discussed.