Related Experiment Videos
Regulation of CD34 expression in differentiating M1 cells
D S Krause1, S U Kapadia, N B Raj
1Johns Hopkins Oncology Center, Baltimore, MD, USA.
Experimental Hematology
|September 18, 1997
Summary
CD34 gene expression in hematopoietic stem cells is regulated at the transcriptional initiation level. Key regulatory elements and transcription factors like Sp1 and Sp3 are involved in this process.
Area of Science:
- Molecular Biology
- Hematopoiesis
- Gene Regulation
Background:
- CD34 is a glycoprotein marker for hematopoietic stem and progenitor cells.
- Understanding CD34 regulation is crucial for stem cell biology and therapeutics.
Purpose of the Study:
- To elucidate the transcriptional regulation of CD34 expression.
- To identify key regulatory elements and factors involved in CD34 gene initiation.
Main Methods:
- Identification of transcription initiation sites (TISs).
- Sequence analysis of upstream genomic DNA.
- Transient transfection assays with promoter-luciferase constructs.
- Electrophoretic mobility shift assays (EMSAs) and supershift experiments.
Main Results:
- Two TISs were identified for the CD34 gene.
- The CD34 promoter is TATA-less and contains an Initiator (INR) element.
- Hematopoietic cell-specific transcription was observed within 454 bp upstream of TISs.
- Sp1 and Sp3 transcription factors bind to a regulatory element in the 5' untranslated region.
Conclusions:
- CD34 downregulation occurs at the transcriptional initiation level.
- Hematopoietic cell-specific factors regulate CD34 expression.
- Optimal CD34 expression involves interaction with Sp1, Sp3, and a 5' untranslated region element.