Article

The interplay between the master transcription factor PU.1 and miR-424 regulates human monocyte/macrophage differentiation.

Institute Pasteur Cenci-Bolognetti, Department of Genetics and Molecular Biology, Institute of Molecular Biology and Pathology, and Department of Cellular Biotechnologies and Hematology, University of Rome "La Sapienza", Rome, Italy.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 01/2008; 104(50):19849-54. DOI: 10.1073/pnas.0706963104
Source: PubMed

ABSTRACT We describe a pathway by which the master transcription factor PU.1 regulates human monocyte/macrophage differentiation. This includes miR-424 and the transcriptional factor NFI-A. We show that PU.1 and these two components are interlinked in a finely tuned temporal and regulatory circuitry: PU.1 activates the transcription of miR-424, and this up-regulation is involved in stimulating monocyte differentiation through miR-424-dependent translational repression of NFI-A. In turn, the decrease in NFI-A levels is important for the activation of differentiation-specific genes such as M-CSFr. In line with these data, both RNAi against NFI-A and ectopic expression of miR-424 in precursor cells enhance monocytic differentiation, whereas the ectopic expression of NFI-A has an opposite effect. The interplay among these three components was demonstrated in myeloid cell lines as well as in human CD34+ differentiation. These data point to the important role of miR-424 and NFI-A in controlling the monocyte/macrophage differentiation program.

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Available from: Alessandro Rosa, May 20, 2014
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