GATA factors are essential for transcription of the survival gene E4bp4 and the viability response of interleukin-3 in Ba/F3 hematopoietic cells.
E4bp4, a member of the basic region/leucine zipper transcription factor superfamily, is up-regulated by the interleukin-3 (IL-3) signaling pathway and plays an important role in the anti-apoptotic response of IL-3. In this study, we demonstrated that E4bp4 is regulated by IL-3 mainly at the transcriptional level. Promoter analysis revealed that a GATA motif downstream of a major transcription initiation site is essential for E4bp4 expression in the IL-3-dependent Ba/F3 cell line. Gel shift assays demonstrated that both GATA-1 and GATA-2 proteins bind to the E4bp4 GATA site in vitro, and the chromatin immunoprecipitation assay further confirmed the in vivo binding of GATA-1 to the E4bp4 promoter. Overexpression of GATA-1 alone transactivates the E4bp4 reporter, whereas transactivation of the E4bp4 reporter by GATA-2 is dependent on the stimulation of IL-3. Last, we demonstrated that alteration of GATA-1 binding to the GATA site by stably overexpressing GATA-1 or a GATA-1 mutant containing only the DNA-binding domain not only modulates the expression of the E4bp4 gene but also influences apoptosis induced by IL-3 removal. Taken together, our results suggest that the GATA factors play an important role in transducing the survival signal of IL-3, and one of their cellular targets is E4bp4.
Yu
Yung-Luen
YL
Graduate Institute of Life Sciences, National Defense Medical Center, Academia Sinica, No. 128, Sec. 2, Yen-Jiou-Yuan Road, Taipei, 115 Taiwan.
Chiang
Yun-Jung
YJ
Yen
Jeffrey J Y
JJ
D000818:Animals; D017209:Apoptosis; D001483:Base Sequence; D050976:Basic-Leucine Zipper Transcription Factors; D015152:Blotting, Northern; D015153:Blotting, Western; D002470:Cell Survival; D002843:Chromatin / Q000378:metabolism; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D018274:Electroporation; D050981:Erythroid-Specific DNA-Binding Factors; D051790:G-Box Binding Factors; D050982:GATA1 Transcription Factor; D050989:GATA2 Transcription Factor; D017930:Genes, Reporter; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D007377:Interleukin-3 / Q000378:metabolism*; D008156:Luciferases / Q000378:metabolism; D051379:Mice; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D015719:Single-Strand Specific DNA and RNA Endonucleases / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic; D015533:Transcriptional Activation
D050976:Basic-Leucine Zipper Transcription Factors; D002843:Chromatin; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D051790:G-Box Binding Factors; D050982:GATA1 Transcription Factor; D050989:GATA2 Transcription Factor; C494689:Gata1 protein, mouse; C494712:Gata2 protein, mouse; D007377:Interleukin-3; C497441:Nfil3 protein, mouse; D012333:RNA, Messenger; D014157:Transcription Factors; D004247:DNA; D008156:Luciferases; D015719:Single-Strand Specific DNA and RNA Endonucleases