摘要
Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok during 24 year-evolution(1977-2000) comparing to the DEN3prototype(H87).Methods:The 5'UTRs of these Thai DEN3 and the H87 prototype were amplified by RT-PCR and sequenced.Their multiple sequence alignments were done by Codon Code Aligner v 4.0.4 software and their RNA secondary structures were predicted by MFOLD software.Replication of five Thai DEN3 candidates comparing to the 1187 prototype were done in human(HepG2) and the mosquito(C6/36) cell lines.Results:Among these Thai DEN3,the completely identical sequences of their first 89 nucleotides,their high-order secondary structure of 5'UTRs and three SNPs including the predominant C90 T,and two minor SNPs including A109 G and A112 G were found.The C90 T of Thai DEN3.Bangkok isolates was shown predominantly before 1977.Five Thai DEN3 candidates with the predominant C90 T were shown to replicate in human(HepG2) and the mosquito(C6/36) cell lines better than the H87 prototype.However,their highly conserved sequences as well as SNPs of the 5'UTR did not appear to correlate with their disease severity in human.Conclusions:Our findings highlighted evolutionary relationship of the completely identical 89 nucleotide sequence,the high-order secondary structure and the predominant C90 T of the 5'UTR of these Thai DEN3 during 24 year-evolution further suggesting to be their genetic markers and magic targets for future research on antiviral therapy as well as vaccine approaches of Thai DEN3.
Objective:To study evolutionary relationship of the 5’untranslated regions(5’UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok during 24 year-evolution(1977-2000) comparing to the DEN3prototype(H87).Methods:The 5’UTRs of these Thai DEN3 and the H87 prototype were amplified by RT-PCR and sequenced.Their multiple sequence alignments were done by Codon Code Aligner v 4.0.4 software and their RNA secondary structures were predicted by MFOLD software.Replication of five Thai DEN3 candidates comparing to the 1187 prototype were done in human(HepG2) and the mosquito(C6/36) cell lines.Results:Among these Thai DEN3,the completely identical sequences of their first 89 nucleotides,their high-order secondary structure of 5’UTRs and three SNPs including the predominant C90 T,and two minor SNPs including A109 G and A112 G were found.The C90 T of Thai DEN3.Bangkok isolates was shown predominantly before 1977.Five Thai DEN3 candidates with the predominant C90 T were shown to replicate in human(HepG2) and the mosquito(C6/36) cell lines better than the H87 prototype.However,their highly conserved sequences as well as SNPs of the 5’UTR did not appear to correlate with their disease severity in human.Conclusions:Our findings highlighted evolutionary relationship of the completely identical 89 nucleotide sequence,the high-order secondary structure and the predominant C90 T of the 5’UTR of these Thai DEN3 during 24 year-evolution further suggesting to be their genetic markers and magic targets for future research on antiviral therapy as well as vaccine approaches of Thai DEN3.
基金
supported by two research grants of Associate Professor Dr.W.Attatippaholkun:Grant No.493-5600-G-00-3461,Program in Science and Technology Cooperation,Human Capacity Development,Bureau for Global Programs,Field Support and Research,US Agency for International Development,Washington,DC
The Royal Golden Jubilee-Ph.D Program,Thailand Research Fund,Thailand
