A GATA Binding Site Is Involved in the Regulation of 15-lipoxygenase-1 Expression in Human Colorectal Carcinoma Cell Line, caco-2

FEBS Lett. 2000 Feb 11;467(2-3):341-7. doi: 10.1016/s0014-5793(00)01155-8.

Abstract

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.

MeSH terms

  • Arachidonate 15-Lipoxygenase / genetics
  • Arachidonate 15-Lipoxygenase / metabolism*
  • Binding Sites
  • Blotting, Western
  • Caco-2 Cells
  • Carcinoma
  • Cell Differentiation
  • Colorectal Neoplasms
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Erythroid-Specific DNA-Binding Factors
  • GATA4 Transcription Factor
  • GATA6 Transcription Factor
  • Gene Expression Regulation
  • Humans
  • Promoter Regions, Genetic
  • RNA, Messenger / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • DNA-Binding Proteins
  • Erythroid-Specific DNA-Binding Factors
  • GATA4 Transcription Factor
  • GATA6 Transcription Factor
  • GATA6 protein, human
  • RNA, Messenger
  • Transcription Factors
  • Arachidonate 15-Lipoxygenase