Abstract
IL-22 is a novel T and NK cell cytokine that belongs to the IL-10 cytokine family. Here we report the identification of a bovine IL-22 ortholog that is expressed by mitogen activated bovine peripheral blood γ/δ T cells. The full-length bovine IL-22 cDNA contained a 68 bp 5'-untranslated region (UTR), a 570-bp open reading frame, and a 480-bp 3'-UTR. The deduced pre-IL-22 has 190 amino acid residues containing a secretory signal peptide from amino acids 1-33 and several potential N-glycosylation sites. The mature protein is predicted to be a secreted, α-helical molecule. The bovine IL-22 gene is ~7.5 kb in length and is comprised of five introns and six exons, and the first exon is non-coding. Computer analysis and gel shift assay showed that the -1132 and -879 region in the 5' upstream gene sequence contained putative transcription factor binding sites for STATx, Sox-5/9, Sp1, Ik-1, and AREB6. Mutagenesis of STATx and Sox5/9 binding sites decreased promoter functionality by ~50%, suggesting their importance in transcription regulation of IL-22. Expression of IL-22 transcripts induced by various mitogens indicated existence of two regulatory control pathways in γ/δ T cells; IL-2 or PMA treatment induced a slow accumulation of IL-22 mRNA without affecting the maximum induction pathway, whereas ConA treatment rapidly induced a limited amount of IL-22 transcripts. Similar maximal levels of IL-22 transcripts could be induced in γ/δ T cells and γ/δ T cells. We conclude that bovine γ/δ T cells are important sources of IL-22 and suggest a role for this cytokine in regulating immune responses at mucosal surfaces, including the gut.
Original language | English (US) |
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Article number | 36645 |
Pages (from-to) | 6-14 |
Number of pages | 9 |
Journal | Gene |
Volume | 451 |
Issue number | 1-2 |
DOIs | |
State | Published - Feb 2010 |
Bibliographical note
Funding Information:This work was supported in part by USDA grants 99-352058618 and 00-521009612.
Keywords
- GFP
- Gamma/delta T cells
- Green fluorescent protein
- Interleukin-22
- LPS
- Lipopolysaccharide
- Promoter
- QRT-PCR
- Quantitative real time PCR
- UTR
- Untranslated region