Related Experiment Videos
Regulation of eosinophil-specific gene expression by a C/EBP-Ets complex and GATA-1
K M McNagny1, M H Sieweke, G Döderlein
1Department of Medical Genetics, Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada V6T 1Z3.
The EMBO Journal
|July 3, 1998
Summary
The EOS47 promoter drives eosinophil differentiation in chickens. Transcription factors like Ets, C/EBP, GATA, and Myb bind cooperatively to regulate this early eosinophil marker, crucial for lineage determination.
Area of Science:
- Hematopoiesis
- Molecular Biology
- Gene Regulation
Background:
- EOS47 is an early and specific marker for eosinophil differentiation in the chicken hematopoietic system.
- Understanding the transcriptional control of eosinophil lineage commitment is essential.
Purpose of the Study:
- To elucidate the transcriptional events regulating the eosinophil-specific EOS47 promoter.
- To identify the transcription factors involved in controlling eosinophil lineage commitment.
Main Methods:
- Studied the regulation of the TATA-less EOS47 promoter.
- Utilized co-transfection experiments in Q2bn fibroblasts.
- Investigated binding sites for Ets, C/EBP, GATA, and Myb families.
Main Results:
- A 309 bp promoter fragment was sufficient for specific high-level transcription in an eosinophil cell line.
- Cooperative activation by c-Myb, Ets-1/Fli-1, GATA-1, and C/EBPalpha was observed.
- Ets-1/Fli-1 and C/EBPalpha showed potent synergistic activation through juxtaposed binding sites.
- Ets-1 and C/EBPalpha proteins physically associated and bound cooperatively.
- GATA-1 exhibited biphasic regulation, activating at low and repressing at high concentrations.
Conclusions:
- Combinatorial activation of the EOS47 promoter involves ubiquitous and lineage-restricted hematopoietic transcription factors.
- Direct interactions between C/EBPs, Ets family members, and GATA-1 are critical for eosinophil lineage determination.