In this work, we report cDNA cloning of two type I interferons (IFNs) from the head kidney of Atlantic salmon, called SasaIFN-α1 (829 bp) and SasaIFN-α2 (1290 bp). Both translate into 175 amino acid precursor molecules showing 95% amino acid sequence identity. The precursors have a putative 23 amino acid signal peptide, which suggests that the mature Atlantic salmon IFNs contain 152 amino acids (18.2 kDa). Salmon IFN appears to have five α-helices, similar to mammalian and avian type I IFNs, and showed 45% sequence identity with zebrafish IFN, up to 29% identity with mammalian IFN-α sequences, and 17%-18% sequence identity with mammalian IFN-β and chicken type I IFNs. Human embryonic kidney 293 cells transfected with the SasaIFN-α1 cDNA gene produced high titers of acid-stable antiviral activity, which protected salmonid cells against infectious pancreatic necrosis virus (IPNV) and also induced Mx protein in the cells. Poly(I)-poly(C) induced two IFN transcripts in head kidney of Atlantic salmon. Genomic IFN sequences contained four introns and five exons, which is different from the intronless type I IFN genes of birds and mammals.
The translation initiation factor 2 alpha (eIF2α)‐kinase, dsRNA‐activated protein kinase (PKR), constitutes one of the major antiviral proteins activated by viral infection of vertebrates. PKR is activated by viral double‐stranded RNA and subsequently phosphorylates the α‐subunit of translation initiation factor eIF2. This results in overall down regulation of protein synthesis in the cell and inhibition of viral replication. Fish appear to have a PKR‐like protein that has Z‐DNA binding domains instead of dsRNA binding domains in the regulatory domain, and has thus been termed Z‐DNA binding protein kinase (PKZ). We present the cloning of the Atlantic salmon PKZ cDNA and show its upregulation by interferon in Atlantic salmon TO cells and poly inosinic poly cytodylic acid in head kidney. We also demonstrate that recombinant Atlantic salmon PKZ, expressed inEscherichia coli, phosphorylates eIF2αin vitro. This is the first demonstration that PKZ is able to phosphorylate eIF2α. PKZ activity, as measured by phosphorylation of eIF2α, was increased after addition of Z‐DNA, but not by dsRNA. In addition, we show that wild‐type Atlantic salmon PKZ, but not the kinase defective variant K217R, has a direct inhibitory effect on protein synthesis after transient expression in Chinook salmon embryo cells. Overall, the results support a role for PKZ, like PKR, in host defense against virus infection.
Learning and development in early childhood is highly dependent on social interaction and exploration through continuous encounters with the real world. Foraging and gardening are outdoor pedagogical practices that have relevance to education for sustainability. Previous work suggests that engagement in such activities can be characterized by the concept “community of practice” (CoP). In this paper, we explore how characteristics of the CoP can be recognized in foraging and gardening projects performed in the Arctic region of Norway, and we discuss how these activities can contribute to social and cultural aspects of sustainability. Data collection included focus group interviews with kindergarten staff (teachers and assistants) and videos taken of foraging and gardening activities with the children. Our data indicate that the hallmarks of CoP, domain, community, and practice, are strongly recognized in these projects through increased interest, social interaction, and agency for learning. This mutual engagement and participation in the CoPs for foraging and gardening connect both staff and children to local food heritage and culture for a sustainable future.