Yellow fever is a
zoonotic disease caused by the
yellow fever virus (YFV) and transmitted by
mosquitoes of the
family Culicidae . It is well known that cellular and viral
microRNAs (
miRNAs ) are involved in modulation of viral and cellular
gene expression , as well as
immune response , and are considered by the scientific
community as possible targets for an effective
therapy against
viral infections . This
regulation may be involved in different levels of
infection and clinical symptomatology. We used viral titration
techniques , viral
kinetics from 24 to 96 hours postinfection (hpi), and analyzed the expression of key
proteins related to the
miRNA pathway by quantitative
reverse transcriptase polymerase chain reaction (qRT-
PCR ). The expression of Dicer was different when compared over the
course of
infection by the distinct YFV
genotypes . Drosha expression was
similar during
infection by YFV
genotype 1 or 2, with a decrease in their expression over
time and a slight increase in 96 hpi. Ago1, Ago2, and Ago4 showed different levels of expression between the viral
genotypes for YFV
genotype 1
infection , Ago1 presented a positive expression, while for YFV
genotype 2, it showed a negative expression, when compared with negative controls. We conclude that YFV
infection modulates the
proteins involved in
miRNA biogenesis, which can regulate both
viral replication and
cellular immune response .