GATA-1 and NF-Y cooperate to mediate erythroid-specific transcription of Gfi-1B gene.
Expression of Gfi (growth factor-independence)-1B, a Gfi-1-related transcriptional repressor, is restricted to erythroid lineage cells and is essential for erythropoiesis. We have determined the transcription start site of the human Gfi-1B gene and located its first non-coding exon approximately 7.82 kb upstream of the first coding exon. The genomic sequence preceding this first non-coding exon has been identified to be its erythroid-specific promoter region in K562 cells. Using gel-shift and chromatin immunoprecipitation (ChIP) assays, we have demonstrated that NF-Y and GATA-1 directly participate in transcriptional activation of the Gfi-1B gene in K562 cells. Ectopic expression of GATA-1 markedly stimulates the activity of the Gfi-1B promoter in a non-erythroid cell line U937. Interestingly, our results have indicated that this GATA-1-mediated trans-activation is dependent on NF-Y binding to the CCAAT site. Here we conclude that functional cooperation between GATA-1 and NF-Y contributes to erythroid-specific transcriptional activation of Gfi-1B promoter.
Graduate Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, No. 1 Jen Ai Road 1st Section, Taipei, Taiwan, Republic of China.
Duen-Yi
DY
Huang
Yuan-Yeh
YY
Kuo
Jiann-Shiun
JS
Lai
Yutaka
Y
Suzuki
Sumio
S
Sugano
Zee-Fen
ZF
Chang
D020121:5' Untranslated Regions; D001483:Base Sequence; D001665:Binding Sites; D023081:CCAAT-Binding Factor / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000502:physiology*; D041905:Erythroid Cells / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D006801:Humans; D020014:K562 Cells; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics*; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics*; D014157:Transcription Factors / Q000502:physiology*; D015533:Transcriptional Activation; D020298:U937 Cells
D020121:5' Untranslated Regions; D023081:CCAAT-Binding Factor; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; C111977:GFI1B protein, human; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D014157:Transcription Factors