[Sequence diversity of the 3' end genome for Zucchini yellow mosaic virus isolates]

The present study analyzed the 3' end sequence of nine mainland isolates of Zucchini yellow mosaic virus (ZYMV) genome including the coat protein (CP) gene and 3' end un-translated region (UTR). Obtained sequence data was compared with previously reported sequences of 16 ZYMV isolates from other regions of the world. In a certain degree, similarity of nucleic acid sequence for CP gene was found being related with the host origin and geological distribution, but not very obvious. Similarity of the CP amino acid sequences deduced from nucleic acid sequences of the 25 ZYMV isolates reached a higher sequence similarity and a clearer relationship to the host origins than to the geological distributions. According to its variation, the amino acid sequence of ZYMV CP was divided into two parts--"the high variable region" contains about 41 amino acids at its N end, while "the conservative region" includes CP core-region and C termini amino acids. Our results showed that the trend of ZYMV variation for its rapid adoption for fitness of the ecological condition, especially to host interaction by mutation of its genomic RNA.