Shrimp interferon is rather a portion of the mitochondrial F0-ATP synthase than a true alpha-interferon.
Type I interferon (IFN) is a multimember cytokine family commonly known by its involvement in antiviral defense. Recently (2005), an interferon-like protein (IntlP) homologue to mammalian IFN-alpha was identified for the first time in crustaceans, in the shrimp Penaeus (Marsupenaeus) japonicus. IntlP was expressed only in WSSV-resistant shrimps (but not in naïve shrimps) and was capable to induce an unspecific antiviral effect on infected fish cells. In the present paper we show that IntlP is in reality a portion of the mitochondrial F0-ATP synthase (60-73% identity with insect F0-ATP synthase beta-chain) and not a homologue of mammalian type I interferon. In our hands, sequences corresponding to IntlP/F0-ATP synthase beta-chain were equally amplified in naïve and WSSV-infected Litopenaeus vannamei and also in two wild Brazilian shrimp species. From the obtained results we assumed that type I IFN homologues have not yet been demonstrated in any shrimp or crustacean.
Laboratório de Imunologia Aplicada à Aqüicultura, Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
Rafael Diego
RD
Rosa
Margherita Anna
MA
Barracco
D000595:Amino Acid Sequence; D000818:Animals; D016898:Interferon-alpha / Q000737:chemistry*; D025261:Mitochondrial Proton-Translocating ATPases / Q000737:chemistry*; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000276:immunology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D016898:Interferon-alpha; D025261:Mitochondrial Proton-Translocating ATPases