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Updated: Oct 25, 2025
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Identification and Analysis of Mouse Erythroid Progenitors using the CD71/TER119 Flow-cytometric Assay
Published on: August 5, 2011
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A Positive Regulatory Feedback Loop between EKLF/KLF1 and TAL1/SCL Sustaining the Erythropoiesis
Chun-Hao Hung1,2, Tung-Liang Lee1, Anna Yu-Szu Huang1,3
1Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan.
International Journal of Molecular Sciences
|August 7, 2021
Summary
Erythroid Krüppel-like factor (EKLF/KLF1) and TAL1/SCL form a positive regulatory feedback loop. This loop is crucial for sustaining mammalian erythropoiesis, the process of red blood cell development.
Area of Science:
- Hematology
- Molecular Biology
- Genetics
Background:
- Erythroid Krüppel-like factor (EKLF/KLF1) is a key hematopoietic transcription factor regulating erythroid differentiation.
- EKLF/KLF1 binds to the CACCC DNA motif, influencing gene expression during red blood cell development.
Purpose of the Study:
- To identify direct target genes and regulatory pathways controlled by EKLF/KLF1.
- To elucidate the molecular mechanisms underlying the positive regulation of erythropoiesis.
Main Methods:
- Gene expression profiling (microarray) and ChIP-chip assays in wild type and EKLF-knockout mouse embryos.
- Analysis of mouse erythroleukemic cells (MEL).
- Promoter identification, in vivo genomic footprinting, and DNA reporter assays.
Main Results:
- EKLF/KLF1 directly activates the Tal1/Scl gene, which encodes the transcription factor TAL1/SCL.
- EKLF/KLF1 binds to a specific CACCC motif in the Tal gene promoter to mediate activation.
- A positive regulatory feedback loop between EKLF/KLF1 and TAL1/SCL was identified.
Conclusions:
- EKLF/KLF1 and TAL1/SCL form a crucial positive regulatory feedback loop.
- This feedback loop is essential for sustaining mammalian erythropoiesis.
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