Size heterogeneity in the 3' noncoding region of South American isolates of yellow fever virus
Journal of virology
; 79(6): 3807-3821, Mar. 2005. graf, tab, ilus
Article
in English
| MedCarib
| ID: med-17658
Responsible library:
TT5
Localization: TT5; W1, JO97V
ABSTRACT
The 3' noncoding region (3' NCR) of flaviviruses contains secondary and tertiary structures essential for virus replication. Previous studies of yellow fever virus (YFV) and dengue virus have found that modifications to the 3' NCR are sometimes associated with attenuation in vertebrate and/or mosquito hosts. The 3' NCRs of 117 isolates of South American YFV have been examined, and major deletions and/or duplications of conserved RNA structures have been identified in several wild-type isolates. Nineteen isolates (designated YF-XL isolates) from Brazil, Trinidad, and Venezuela, dating from 1973 to 2001, exhibited a 216-nucleotide (nt) duplication, yielding a tandem repeat of conserved hairpin, stem-loop, dumbbell, and pseudoknot structures. YF-XL isolates were found exclusively within one subclade of South American genotype I YFV. One Brazilian isolate exhibited, in addition to the 216-nt duplication, a deletion of a 40-nt repeated hairpin (RYF) motif (YF-XL-DeltaRYF). To investigate the biological significance of these 3' NCR rearrangements, YF-XL-DeltaRYF and YF-XL isolates, as well as other South American YFV isolates, were evaluated for three phenotypes growth kinetics in cell culture, neuroinvasiveness in suckling mice, and ability to replicate and produce disseminated infections in Aedes aegypti mosquitoes. YF-XL-DeltaRYF and YF-XL isolates showed growth kinetics and neuroinvasive characteristics comparable to those of typical South American YFV isolates, and mosquito infectivity trials demonstrated that both types of 3' NCR variants were capable of replication and dissemination in a laboratory-adapted colony of A. aegypti.
Full text:
Available
Collection:
International databases
Health context:
Neglected Diseases
Health problem:
Dengue
Database:
MedCarib
Main subject:
Phylogeny
/
Genetic Variation
/
Molecular Sequence Data
/
Base Sequence
/
Cells, Cultured
/
Aedes
/
Nucleic Acid Conformation
Type of study:
Prognostic study
Limits:
Animals
/
Humans
Country/Region as subject:
South America
/
Brazil
/
English Caribbean
/
Trinidad and Tobago
/
Venezuela
Language:
English
Journal:
Journal of virology
Year:
2005
Document type:
Article
Institution/Affiliation country:
Chicago Department of Public Health/United States of America
/
Ministry of Health/Brazil
/
University of Texas/United States of America