A GATA binding site is involved in the regulation of 15‐lipoxygenase‐1 expression in human colorectal carcinoma cell line, Caco‐2

FEBS Letters

Kelavkar, Uddhav P.²  Kameda, Hideto¹  Eling, Thomas E.¹  Kamitani, Hideki¹ 

[1] Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, PO Box 12233, Research Triangle Park, NC 27709, USA;Renal Division and Center Glomerulonephritis, Emory University, Atlanta, GA 30322, USA

关键词: 15-Lipoxygenase-1;    GATA;    Differentiation;    Transcription factor;    LO;    lipoxygenase;    EMSA;    electrophoretic mobility shift assay;    FBS;    fetal bovine serum;    NaBT;    sodium butyrate;    EGFR;    epidermal growth factor receptor;   

DOI  :  10.1016/S0014-5793(00)01155-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The data presented implicate a GATA binding site in the transcriptional regulation of 15-lipoxygenase-1 (15-LO-1) gene expression in human colorectal carcinoma Caco-2 cells. High expression of GATA-6 mRNA and protein was observed, while GATA-4 mRNA was expressed at a very low level in Caco-2 cells. The expression of GATA-6 was down-regulated, while 15-LO-1 expression was dramatically up-regulated after treatment with sodium butyrate (NaBT). A study using an electrophoretic mobility shift assay indicated that a GATA binding site of the 15-LO-1 promoter region binds to GATA proteins present in both undifferentiated and, to a lesser extent, NaBT-treated (differentiated) Caco-2 cells. Moreover, that DNA binding shift band was disrupted after the addition of GATA-6 antibody in a supershift assay in the absence of NaBT, suggesting that GATA-6 is bound to the GATA binding site of the 15-LO-1 promoter in undifferentiated cells. In contrast, the addition of GATA-6 antibody did not affect the DNA binding ability in NaBT-induced differentiated cells. On the other hand, mutation of the GATA site of the 15-LO-1 promoter decreased the transactivation of the 15-LO-1 promoter as measured by luciferase activity in both FBS and NaBT cultured cells, indicating an unknown GATA binding protein to up-regulate 15-LO-1 expression. These implicate the GATA site at −240 of the proximal region of the 15-LO-1 promoter in the basic transcription of 15-LO-1 gene expression in Caco-2 cells, with GATA-6 acting to repress 15-LO-1 expression.

【 授权许可】

Unknown