Article

[Antiviral immunity in drosophila].

UPR9022 CNRS Institut de Biologie Moléculaire et Cellulaire 15, rue René Descartes F-67000 Strasbourg.
Journal de la Société de Biologie 02/2007; 201(4):359-65. DOI:10.1051/jbio:2007906 pp.359-65
Source: PubMed

ABSTRACT Viral diseases represent a constant threat and an important cause of mortality worldwide. We have developed a model to study the response to RNA virus infection in the fruit-fly drosophila. This insect is a good model to study the genetic bases of innate immunity, which constitutes the first level of host-defense in animals. We have shown that viral infection in drosophila triggers a response different from that to bacterial or fungal infections. Our data at this stage point to the existence of at least two types of antiviral defense mechanisms. On one hand, viral infection triggers a JAK-STAT dependent transcriptional response that leads to the expression of antiviral molecules that remain to be characterized. On the other hand, viral RNAs are recognized by Dicer-2 and degraded in siRNAs, thus inducing RNA interference and degradation of viral RNAs. Strikingly, the drosophila antiviral response evokes by some aspects the interferon response in mammals (JAK-STAT pathway) and antiviral defenses in plants (RNA interference).

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Keywords

antiviral defense mechanisms
 
antiviral defenses
 
antiviral molecules
 
drosophila antiviral response evokes
 
first level
 
fungal infections
 
genetic bases
 
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inducing RNA interference
 
innate immunity
 
interferon response
 
JAK-STAT dependent transcriptional response
 
JAK-STAT pathway
 
response different
 
RNA virus infection
 
stage point
 
two types
 
Viral diseases
 
viral infection
 
viral RNAs