Organization and promoter analysis of the zebrafish (Danio rerio) chemokine gene (CXC-64) promoter.
Zebrafish CXC-64, a chemokine representing a superfamily of chemotactic cytokines present in fish, is involved in recruitment, activation, and response to inflammatory stimulation. We cloned and sequenced the genomic DNA of the zebrafish CXC-64 chemokine; it was most similar to CXCL11 from humans and CXCL10 from a catfish. The zebrafish CXC-64 gene is approximately 4.0 kb long and has a four-exon, three-intron structure common to the human CXCL11 gene. However, the promoter region includes a typical TATA box and multi-transcription factor-binding sequences. To understand the roles of lipopolysaccharide (LPS), poly I:poly C, and tumor necrosis factor (TNF)-alpha in regulating zebrafish CXC-64 expression, serial deletions were made in the promoter region of this clone. Different fragments of the zebrafish CXC-64 5'-flanking region were transfected into RAW264.7 (mouse macrophage; Abelson murine leukemia virus transformed) and zfl (zebrafish liver) cells and then treated with 0, 10, 50, 100, and 200 ng/ml LPS, poly I:poly C, or TNF-alpha. The results showed that the promoter activity presented dose-dependent effects in LPS-treated RAW264.7 cells, TNF-alpha-treated RAW264.7 cells, and LPS-treated zfl cells. These results reveal that the zebrafish CXC-64 chemokine gene promoter region can be induced by LPS in both human and fish cell lines, which suggests that it plays an important role in regulating LPS.
Chen
Li-Chen
LC
Department of Food Science, National Taiwan Ocean University, Keelung, 202, Taiwan.|Department of Food Science, National I-Lan University, Ilan, 260, Taiwan.
Wu
Jen-Leih
JL
Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, 115, Taiwan.
Shiau
Chyuan-Yuan
CY
Department of Food Science, National Taiwan Ocean University, Keelung, 202, Taiwan.
Chen
Jyh-Yih
JY
Marine Research Station, Institute of Cellular and Organismic Biology, Academia Sinica, 23-10 Dahuen Road, Jiaushi, Ilan, 262, Taiwan. zoocjy@gate.sinica.edu.tw.
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D019743:Chemokines, CXC / Q000235:genetics*; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D040461:Gene Components; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D008070:Lipopolysaccharides / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015027:Zebrafish / Q000235:genetics*
D019743:Chemokines, CXC; D017931:DNA Primers; D008070:Lipopolysaccharides; D011956:Receptors, Cell Surface; D014409:Tumor Necrosis Factor-alpha; C045250:poly I-C receptor