Molecular identification of cucumber mosaic virus in woad (Isatis tinctoria) with mosaic disease in Beijing / 中国中药杂志

To detect possible pathogenic virus(es) in woad (Isatis tinctoria) cultivated at Institute of Medicinal Plant Development in Beijing, reverse transcription(RT)-PCR was performed using total RNA of symptomatic woad leaves with primers for poty-, polero-, tobamovirus, broad bean wilt virus 2(BBWV2) and cucumber mosaic virus (CMV). A 657 bp fragment was amplified from symptomatic woad using CMV primers. Sequencing and BLAST analysis indicated that this fragment shared 99% nucleotide identity and 100% amino acid identity with CMV-Vi isolate. The isolate was named CMV-Isatis tinctorial (CMV-It). Phylogenetic analysis based on nucleotide sequences of CP genes showed that CMV-It clustered with CMV-K and belonged to subgroup I. To our knowledge, this is first identification of CMV in woad by RT-PCR and the CP gene was analyzed. This work provided data for research and control of woad mosaic disease.

Sequence Analysis of Coat Protein Gene of Cucumber Mosaic Virus Isolate Infecting Basella rubra L / 中国生物工程杂志

Cucumber mosaic virus was detected from infected Basella rubra L. with the indirect enzyme-linked immunosorbent assay. Total RNA was extracted from infected leaves and the cDNAs of coat protein gene of CMV-Ba were obtained by RT-PCR. The amplified cDNA fragments were then cloned into pMD 18-T vector and sequenced,the result showed that the CP gene was 657 nucleotides in length. This sequence was aligned with the obtained CP gene and some CMV strains or isolates of subgroup Ⅰ and subgroup Ⅱ in GenBank using DNA MAN software. The results showed that CMV-Ba shared 90.9%~93.8% and 76.1%~76.9% identity with the known CP genes of subgroup Ⅰ and Ⅱ respectively in nucleotide level,on the other hand,amino acids deduced from CMV-Ba CP gene shared 92.7%~97.7% and 72.4%~78.1% identity with the known CP protein of subgroup Ⅰ and Ⅱ,respectively. This suggested that CMV-Ba CP gene belongs to CMV subgroupⅠ.