Complete nucleotide sequence analysis of Cymbidium mosaic virus Indian isolate: further evidence for natural recombination among potexviruses

Abstract

The complete nucleotide sequence of an Indian strain of Cymbidium mosaic virus (CymMV)was determined and compared with other potexviruses. Phylogenetic analyses on the basis of RNA-dependent RNA polymerase (RdRp), triple gene block protein and coat protein (CP) amino acid sequences revealed that CymMV is closely related to the Narcissus mosaic virus (NMV), Scallion virus X (SVX), Pepino mosaic virus (PepMV)and Potato aucuba mosaic virus (PAMV). Different sets of primers were used for the amplification of different regions of the genome through RT-PCR and the amplified genes were cloned in a suitable vector. The full genome of the Indian isolate of CymMV from Phaius tankervilliae shares 96-97% similarity with isolates reported from other countries. It was found that the CP gene of CymMV shares a high similarity with each other and other potexviruses. One of the Indian isolates seems to be a recombinant formed by the intermolecular recombination of two other CymMV isolates. The phylogenetic analyses, Recombination Detection Program (RDP2)analyses and sequence alignment survey provided evidence for the occurrence of a recombination between an Indian isolate (AM055720) as the major parent, and a Korean type-2 isolate (AF016914) as the minor parent. Recombination was also observed between a Singapore isolate (U62963) as the major parent,and a Taiwan CymMV (AY571289) as the minor parent.

Cloning and sequence analysis of orchids CymMV and ORSV CP gene isolated in northern of Vietnam

“…CymMV thuộc chi Potexviruses, hệ gen là sợi RNA đơn dương dài 6.227 nucleotide, tổ chức hệ gen gồm 3 vùng gen (RdRp, TGB và CP) với 5 khung đọc mở mã hóa cho các phân tử protein có trọng lượng 160 kDa (RdRp), 26 kDa/13 kDa/10 kDa (MP) và 24 kDa (CP) [5,7]. ORSV là virus đốm vòng hoa lan, gây ra các đốm vòng hoại tử màu đen nâu trên thân, lá và hoa [2].…”

Discovering Fragrance Biosynthesis Genes from Vanda Mimi Palmer Using the Expressed Sequence Tag (EST) Approach

“…Fragrance emission is detected only when the flower bud starts to open as none is detected from the closed bud [average size of 0.8-1.4 cm] Janna et al, 2005 Orchids cultivation entails hard work as the orchids can be easily infected by orchidinfecting viruses. More than 50 orchid-infecting viruses have been detected worldwide, with cymbidium mosaic virus (CymMV) and odontoglossum ringspot tobamovirus (ORSV) infections being the most prevalent (Sherpa et al, 2007). Infected orchid cultivars usually exhibit blossoms with brown necrotic streaks and other necrosis symptoms.…”

“…Infected flowers are smaller in size and poorer in quality. This has caused severe economic damages in the cut flower and potted plant industry (Ajjikuttira et al, 2002;Sherpa et al, 2007;Vejaratpimol et al, 1999). CymMV infection is dominant and extremely stable in Orchidaceae, and it was found to be prevalent in VMP.…”

Genetic variability in the coat protein genes of Cymbidium mosaic virus isolates from orchids

“…To date, the complete nucleotide (nt) sequences of 11 CymMV isolates have been reported [9,[12][13][14][15][16]. There have been several reports about the molecular variability of CymMV isolates.…”