Title: VARYING GENETIC DIVERSITY OF PAPAYA RINGSPOT VIRUS ISOLATES FROM TWO TIME-SEPARATED OUTBREAKS IN JAMAICA AND VENEZUELA
Chin, Melaine - BIOTECH CENTRE, JM
Rojas, Y. - UNIVERSIDAD DE LOS ANDES
Moret, J. - UNIVERSIDAD DE LOS ANDES
Fermin, Gustavo - UNIV LOS ANDES, VE
Tennant, Paula - UNIV W. INDIES, JM
Submitted to: Archives of Virology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 14, 2007
Publication Date: October 1, 2007
Citation: Chin, M., Rojas, Y., Moret, J., Fermin, G., Tennant, P., Gonsalves, D. 2007. Varying genetic diversity of papaya ringspot virus isolates from two time-separated outbreaks in Jamaica and Venezuela. Archives of Virology 152, 2101-2106.
Interpretive Summary: Papaya ringspot virus (PRSV) causes the most important virus disease of papaya worldwide. Research has shown that resistance of transgenic papaya to PRSV can be overcome by strains of PRSV, and that the ability to overcome the resistance is due to the divergence of the coat protein sequences of the virus strains. Since transgenic papaya has been developed for Jamaica, it is important to determine the relative divergence of coat protein sequences of PRSV strains in Jamaica. Sequences of coat protein strains of PRSV from Jamaica were obtained and analyzed. These studies may help to predict the effectiveness of the transgenic papaya in Jamaica.
The coat protein (CP) genes of eleven Jamaican Papaya ringspot virus type-p (PRSV) isolates that were collected in 1999 were cloned and sequenced. The nucleotide and amino acid sequences of these isolates were compared to each other, with a sequence of another Jamaican isolate collected after the first PRSV epidemic in 1990, and with those of over one hundred isolates from different parts of the world. The percentages nucleotide similarity amongst the year 1999 Jamaican isolates ranged from 98 to 100%, but isolates originating the two time periods shared lower average values of 92 and 91%, for nt and aa, respectively. Nucleotide sequence comparisons with isolates from different geographical locations revealed a closer relationship to Australian, Hawaiian, and isolates from the Americas (89.1 to 98.6%) than to Asian isolates (87.8 to 89.2) of PRSV. Although divergent to the 1990 isolate, the 1999 Jamaican isolates always branch with the latter, thus, confirming their Jamaican origin. The implications of controlling the disease with transgenic plants developed with sequences of the isolates from the first epidemic are discussed.