Avian influenza rapidly induces antiviral genes in duck lung and intestine.
ABSTRACT Ducks are the natural reservoir of influenza A and survive infection by most strains. To characterize the duck immune response to influenza, we sought to identify innate immune genes expressed early in an infection. We used suppressive subtractive hybridization (SSH) to construct 3 libraries enriched in differentially expressed genes from lung RNA of a duck infected with highly pathogenic avian influenza virus A/Vietnam/1203/04 (H5N1), or lung and intestine RNA of a duck infected with low pathogenic avian influenza A/mallard/BC/500/05 (H5N2) compared to a mock-infected duck. Sequencing of 1687 clones identified a transcription profile enriched in genes involved in antiviral defense and other cellular processes. Major histocompatibility complex class I (MHC I), interferon induced protein with tricopeptide repeats 5 (IFIT5), and 2'-5' oligoadenylate synthetase-like gene (OASL) were increased more than 1000-fold in relative transcript abundance in duck lung at 1dpi with highly pathogenic VN1203. These genes were induced much less in lung or intestine following infection with low pathogenic BC500. The expression of these genes following infection suggests that ducks initiate an immediate and robust response to a potentially lethal influenza strain, and a minimal response to a low pathogenic strain.
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ABSTRACT: Secretion of interferons (IFNs) from virus-infected cells is a hallmark of host antiviral immunity and in fact, IFNs exert their antiviral activities through the induction of antiviral proteins. The IFN-induced protein with tetratricopeptide repeats () family is among hundreds of IFN-stimulated genes. This family contains a cluster of duplicated loci. Most mammals have , , and ; however, bird, marsupial, frog and fish have only . Regardless of species, is always adjacent to . family genes are predominantly induced by type I and type III interferons and are regulated by the pattern recognition and the JAK-STAT signaling pathway. family proteins are involved in many processes in response to viral infection. However, some viruses can escape the antiviral functions of the family by suppressing family genes expression or methylation of 5' cap of viral molecules. In addition, the variants of family genes could significantly influence the outcome of hepatitis C virus (HCV) therapy. We believe that our current review provides a comprehensive picture for the community to understand the structure and function of family genes in response to pathogens in human, as well as in animals.International journal of biological sciences 01/2013; 9(2):200-8. · 3.17 Impact Factor