Phylogenetic analysis of the envelope protein (domain III) of dengue 4 viruses.
OBJECTIVE
To evaluate the genetic variability of domain III of envelope (E) protein and to estimate phylogenetic relationships of dengue 4 (Den-4) viruses isolated in Mexico and from other endemic areas of the world.


METHODS
A phylogenetic study of domain III of envelope (E) protein of Den-4 viruses was conducted in 1998 using virus strains from Mexico and other parts of the world, isolated in different years. Specific primers were used to amplify by RT-PCR the domain III and to obtain nucleotide sequence. Based on nucleotide and deduced aminoacid sequence, genetic variability was estimated and a phylogenetic tree was generated. To make an easy genetic analysis of domain III region, a Restriction Fragment Length Polymorphism (RFLP) assay was performed, using six restriction enzymes.


RESULTS
Study results demonstrate that nucleotide and aminoacid sequence analysis of domain III are similar to those reported from the complete E protein gene. Based on the RFLP analysis of domain III using the restriction enzymes NIa III, Dde I and Cfo I, Den-4 viruses included in this study were clustered into genotypes 1 and 2 previously reported.


CONCLUSIONS
Study results suggest that domain III may be used as a genetic marker for phylogenetic and molecular epidemiology studies of dengue viruses. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.
Departamento de Arbovirus, Centro de Investigación sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México.
Javier
J
Mota
José
J
Ramos-Castañeda
Rebeca
R
Rico-Hesse
Celso
C
Ramos
D001483:Base Sequence; D003716:Dengue Virus / Q000235:genetics*; D008800:Mexico; D008969:Molecular Sequence Data; D010802:Phylogeny; D014759:Viral Envelope Proteins / Q000235:genetics*
D014759:Viral Envelope Proteins