Article

EKLF restricts megakaryocytic differentiation at the benefit of erythrocytic differentiation.

Université de Lyon, Lyon, France.
Blood (impact factor: 9.9). 08/2008; 112(3):576-84. DOI:10.1182/blood-2007-07-098996 pp.576-84
Source: PubMed

ABSTRACT Previous observations suggested that functional antagonism between FLI-1 and EKLF might be involved in the commitment toward erythrocytic or megakaryocytic differentiation. We show here, using inducible shRNA expression, that EKLF knockdown in mouse erythroleukemia (MEL) cells decreases erythrocytic and increases megakaryocytic as well as Fli-1 gene expression. Chromatin immunoprecipitation analyses revealed that the increase in megakaryocytic gene expression is associated with a marked increase in RNA pol II and FLI-1 occupancy at their promoters, albeit FLI-1 protein levels are only minimally affected. Similarly, we show that human CD34(+) progenitors infected with shRNA lentivirus allowing EKLF knockdown generate an increased number of differentiated megakaryocytic cells associated with increased levels of megakaryocytic and Fli-1 gene transcripts. Single-cell progeny analysis of a cell population enriched in bipotent progenitors revealed that EKLF knockdown increases the number of megakaryocytic at the expense of erythrocytic colonies. Taken together, these data indicate that EKLF restricts megakaryocytic differentiation to the benefit of erythrocytic differentiation and suggest that this might be at least partially mediated by the inhibition of FLI-1 recruitment to megakaryocytic and Fli-1 gene promoters.

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Keywords

bipotent progenitors
 
cell population enriched
 
Chromatin immunoprecipitation analyses
 
differentiated megakaryocytic cells
 
EKLF knockdown
 
EKLF knockdown increases
 
EKLF restricts megakaryocytic differentiation
 
erythrocytic colonies
 
erythrocytic differentiation
 
Fli-1 gene expression
 
Fli-1 gene promoters
 
Fli-1 gene transcripts
 
FLI-1 protein levels
 
increased number
 
inducible shRNA expression
 
megakaryocytic differentiation
 
megakaryocytic gene expression
 
Previous observations
 
RNA pol II
 
Single-cell progeny analysis