Title:Viral-encoded microRNAs in host-pathogen interactions in silkworm
VOLUME: 10
Author(s):C. P. Singh*
Affiliation:Department of Botany, University of Rajasthan, Jaipur-302004, Rajasthan
Keywords:MicroRNA, virus, silkworm, Bombyx mori, insect and host-pathogen interactions, siRNAs.
Abstract:The mulberry silkworm Bombyx mori, apart from its well-known economic importance, has also emerged as an
insect model to study host-pathogen interactions. The major concern for silkworm cultivation and the sericulture industry
is the attack by various types of pathogens mainly includes viruses, fungi, bacteria and protozoa. Successful infection
requires specific arsenals to counter the host immune response. MicroRNAs (miRNAs) are one of the potential arsenals
which are encoded by viruses and effectively used during host-pathogen interactions. MiRNAs are short noncoding 19-25
nucleotides long endogenous RNAs that post-transcriptionally regulate expression of protein-coding genes in a sequencespecific manner. Most of the higher eukaryotes encode miRNAs and utilize them in the regulation of important cellular
pathways. In silkworm, promising functions of miRNAs have been characterized in development, metamorphosis,
immunity, and host-pathogen interactions. The viral miRNA-mediated fine-tuning of the viral, as well as cellular genes, is
beneficial for making a cellular environment favorable for the virus proliferation. Baculovirus and cypovirus which infect
silkworm have been shown to encode miRNAs and their functions are implicated in controlling the expression of both
viral and host genes. In the present review, the author discusses the diverse functions of viral-encoded miRNAs in evasion
of the host immune responses and reshaping of the silkworm cellular environment for replication. Besides, a basic
overview of miRNA biogenesis and mechanism of action is also provided. Our increasing understanding of the viral
miRNAs role in silkworm-virus interactions would not only assist us to get insights into the intricate pathways but also
provide tools to deal with dreaded pathogens.
