In plants and insects, RNA interference (RNAi) is the main responder against viruses and shapes the basis of antiviral immunity.
In addition, the gene dicer was significantly down-regulated with age; this is consistent with the fact that dicer expression is associated with aging and decreased stress resistance in mice and C. elegans [ 38]. dicer also has known roles in insect RNA-interference and antiviral responses [ 39], thus its down-regulation with age may also reflect changes in immune function.
To elucidate their functions in short germ insect development, RNA interference (RNAi -based functional analyses of these genes weRNAi -basedd in the cricket.
Comparative genomic analysis revealed that L. striatellus encodes similar innate immunity regulatory systems as other insects, such as RNA interference, JAK/STAT and partial Imd cascades, which might be involved in defense against viral infection.
Since the discovery that providing double-stranded RNA (dsRNA) to a wide variety of organisms, including insects, can induce RNA interference (RNAi), this method has become a common tool for functional genomic studies, particularly in non-model systems [ 1, 2].
There are still many aspects of this study, which remain unclear; like, how is the systemic RNA interference in host insect arisen.
Tribolium and Nilaparvata lugens, both of the insects in which systemic RNA interference is prominent, have Sid-1 like proteins which have higher sequence similarity with insect Sil than with that of C. elegans Tag-130[ 29, 29].
The Drosophila immune response includes the induction of antimicrobial peptides (AMPs), hemolymph coagulation, melanization, RNA interference (RNAi), and phagocytic insect "blood cells" called hemocytes.
The nematode worm C. elegans also deploys RNA interference against viruses but, in contrast to insects and plants, worms do not possess a specific set of RNA interference enzymes that participate solely in the antiviral response.
It is known to have an increased expression level during wing development in other insects and studies have shown that RNA interference of Ci resulted in wing-reduced phenotypes (Li et al. 2009).
