Eosinophil-specific regulation of gp91(phox) gene expression by transcription factors GATA-1 and GATA-2.
The glycoprotein gp91(phox) is an essential component of the phagocyte NADPH oxidase and is expressed in eosinophils, neutrophils, monocytes, and B-lymphocytes. We previously suggested an eosinophil-specific mechanism of gp91(phox) gene expression. To elucidate the mechanism, we performed functional assays on deletion mutants of the gp91(phox) promoter in various types of gp91(phox)-expressing cells. A 10-base pair (bp) region from bp -105 to -96 of the promoter activated transcription of the gene in eosinophilic cells, but not in neutrophilic, monocytic, or B-lymphocytic cells. A 2-bp mutation introduced into the GATA site spanning bp -101 to -96 (-98GATA site) of the fragment abolished its activity. Gel shift assays using a GATA competitor and specific antibodies demonstrated that both GATA-1 and GATA-2 specifically bound to the -98GATA site with similar affinities. Individual transfection of GATA-1 and GATA-2 into Jurkat cells, which have neither endogenous GATA-1 nor GATA-2, activated the -105/+12 construct in a -98GATA site-dependent manner. Combined transfection of GATA-1 and GATA-2 activated the promoter less than transfection of GATA-1 alone. These results suggest that GATA-1 is an activator and that GATA-2 is a relative competitive inhibitor of GATA-1 in the expression of the gp91(phox) gene in human eosinophils.
Yang
D
D
Department of Host-defense Biochemistry, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
Suzuki
S
S
Hao
L J
LJ
Fujii
Y
Y
Yamauchi
A
A
Yamamoto
M
M
Nakamura
M
M
Kumatori
A
A
D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000502:physiology*; D004804:Eosinophils / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D050989:GATA2 Transcription Factor; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics*; D016297:Mutagenesis, Site-Directed; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases; D011401:Promoter Regions, Genetic; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000502:physiology*; D015533:Transcriptional Activation
D017931:DNA Primers; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; D050989:GATA2 Transcription Factor; C494711:GATA2 protein, human; D008562:Membrane Glycoproteins; D014157:Transcription Factors; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases