Cloning and characterisation of two natural killer enhancing factor genes (NKEF-A and NKEF-B) in pufferfish, Tetraodon nigroviridis

• Published in: Fish & Shellfish Immunology Vol. 22; no. 1; pp. 1 - 15
• Main Authors: Dong, Wei-Ren, Xiang, Li-Xin, Shao, Jian-Zhong
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2007
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Characterization; Cloning, Molecular; Cytotoxicity, Immunologic - genetics; DNA Primers - chemistry; DNA, Complementary - chemistry; Female; Gene cloning; Gene Expression Regulation; Gene Order - genetics; Killer Cells, Natural - immunology; Male; Molecular Sequence Data; NKEF-A; NKEF-B; Peroxiredoxins - chemistry; Peroxiredoxins - genetics; Peroxiredoxins - immunology; Phylogeny; Polymerase Chain Reaction; Promoter Regions, Genetic - genetics; Sequence Alignment; Sequence Homology, Amino Acid; Spotted green pufferfish; Tetraodon; Tetraodon nigroviridis; Tetraodontiformes - genetics; Tetraodontiformes - immunology; Transcription Factors - genetics; Characterization; NKEF-B; Gene cloning; NKEF-A; Spotted green pufferfish; Tetraodon nigroviridis
• ISSN: 1050-4648; 1095-9947; 1365-2567
• DOI: 10.1016/j.fsi.2006.03.007

Natural killer cell enhancing factor (NKEF) belongs to a highly conserved peroxiredoxin (Prx) family. Its functions are involved in immune cytotoxicity, apoptosis, cell proliferation, differentiation and antioxidant activity. In present paper, two NKEF genes, NKEF-A and NKEF-B, were isolated and characterised in spotted green pufferfish, Tetraodon nigroviridis. Comparative genomic location analysis shows conserved syntenies within the NKEF-A and NKEF-B regions between Tetraodon and human, indicating that the Tetraodon NKEF-A and NKEF-B genes are orthologs for mammalian NKEF-A and NKEF-B encoding genes, respectively. The genomic organisation of the two genes is similar in different species, containing one non-coding exon, five coding exons and five introns. The deduced amino acids of the two genes are highly homologous with mammalian NKEF-A and NKEF-B proteins, including two well conserved Val-Cys-Pro (VCP) motifs. Tissue specific expression analysis by RT-PCR reveals that both genes are globally expressed. Stimulation with LPS inhibits both NKEF-A and NKEF-B gene expression in most tissues but enhances NKEF-A and NKEF-B transcriptions in spleen. This is the first report on the existence of a NKEF-B homologue in fish.