MicroRNA 155 modulates megakaryopoiesis at progenitor and precursor level by targeting Ets‐1 and Meis1 transcription factors

MicroRNAs (miRNAs) control basic biological functions and are emerging as key regulators of haematopoiesis. This study focused on the functional role of MIRN155 on megakaryocytic (MK) differentiation of human cord blood CD34+ haematopoietic progenitor cells (HPCs). MIRN155, abundantly expressed in early HPCs, decreases sharply during MK differentiation. Functional studies showed that enforced expression of MIRN155 impairs proliferation and differentiation of MK cells. Furthermore, HPCs transfected with MIRN155 showed a significant reduction of their MK clonogenic capacity, suggesting that down‐modulation of this miRNA favours MK progenitor differentiation. Consistent with this observation, MIRN155 down‐regulates, by directly binding to their 3′‐UTR, the expression of Ets‐1 and Meis1, two transcription factors with well‐known functions in MK cells. These results show that the decline of MIRN155 is required for MK proliferation and differentiation at progenitors and precursors level and indicate that sustained expression of MIRN155 inhibits megakaryopoiesis.

[1]  D. Halbert,et al.  T cell activation induces a noncoding RNA transcript sensitive to inhibition by immunosuppressant drugs and encoded by the proto-oncogene, BIC. , 2002, Cellular immunology.

[2]  D. Watson,et al.  Ets-dependent Regulation of Target Gene Expression during Megakaryopoiesis* , 2004, Journal of Biological Chemistry.

[3]  T. Imanishi,et al.  Both Ets-1 and GATA-1 are essential for positive regulation of platelet factor 4 gene expression. , 1998, European journal of biochemistry.

[4]  C. Croce,et al.  CD34+ hematopoietic stem-progenitor cell microRNA expression and function: A circuit diagram of differentiation control , 2006, Proceedings of the National Academy of Sciences.

[5]  C. Peschle,et al.  "Pure" human hematopoietic progenitors: permissive action of basic fibroblast growth factor. , 1990, Science.

[6]  N. Copeland,et al.  Hematopoietic, angiogenic and eye defects in Meis1 mutant animals , 2004, The EMBO journal.

[7]  Carlo M. Croce,et al.  MicroRNAs 17-5p–20a–106a control monocytopoiesis through AML1 targeting and M-CSF receptor upregulation , 2007, Nature Cell Biology.

[8]  E. Coccia,et al.  Interferon regulatory factor-2 drives megakaryocytic differentiation. , 2004, The Biochemical journal.

[9]  George A Calin,et al.  MicroRNA fingerprints during human megakaryocytopoiesis. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[10]  K. Kaushansky.  Historical review: megakaryopoiesis and thrombopoiesis. , 2008, Blood.

[11]  Wayne Tam,et al.  Accumulation of miR-155 and BIC RNA in human B cell lymphomas. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[12]  M. Weiss,et al.  Megakaryocyte biology and related disorders. , 2005, The Journal of clinical investigation.

[13]  Anton J. Enright,et al.  Requirement of bic/microRNA-155 for Normal Immune Function , 2007, Science.

[14]  Ikuo Morita,et al.  Homeodomain proteins MEIS1 and PBXs regulate the lineage-specific transcription of the platelet factor 4 gene. , 2003, Blood.

[15]  D. Watson,et al.  Hemorrhage, Impaired Hematopoiesis, and Lethality in Mouse Embryos Carrying a Targeted Disruption of the Fli1Transcription Factor , 2000, Molecular and Cellular Biology.

[16]  W. Vainchenker,et al.  FLI1 monoallelic expression combined with its hemizygous loss underlies Paris-Trousseau/Jacobsen thrombopenia. , 2004, The Journal of clinical investigation.

[17]  W. S. Hayward,et al.  bic, a novel gene activated by proviral insertions in avian leukosis virus-induced lymphomas, is likely to function through its noncoding RNA , 1997, Molecular and cellular biology.

[18]  D. Bartel,et al.  MicroRNAs Modulate Hematopoietic Lineage Differentiation , 2004, Science.

[19]  J Philip McCoy,et al.  Hematopoietic-specific microRNA expression in human cells. , 2006, Leukemia research.

[20]  A. Giampaolo,et al.  Different ploidy levels of megakaryocytes generated from peripheral or cord blood CD34+ cells are correlated with different levels of platelet release. , 2002, Blood.

[21]  R. Shivdasani.  MicroRNAs: regulators of gene expression and cell differentiation. , 2006, Blood.

[22]  A. Pasquinelli,et al.  The evolving role of microRNAs in animal gene expression. , 2006, BioEssays : news and reviews in molecular, cellular and developmental biology.

[23]  P. Romeo,et al.  Analysis of the thrombopoietin receptor (MPL) promoter implicates GATA and Ets proteins in the coregulation of megakaryocyte-specific genes. , 1996, Blood.

[24]  A. van den Berg,et al.  BIC and miR‐155 are highly expressed in Hodgkin, primary mediastinal and diffuse large B cell lymphomas , 2005, The Journal of pathology.

[25]  N. Janel,et al.  Ets transcription factors bind and transactivate the core promoter of the  von Willebrand factor gene , 1997, Oncogene.

[26]  R. Shivdasani.  Molecular and Transcriptional Regulation of Megakaryocyte Differentiation , 2001, Stem cells.

[27]  C. Peschle,et al.  Expression of growth factor receptors in unilineage differentiation culture of purified hematopoietic progenitors. , 1996, Blood.

[28]  N. Ahn,et al.  Extracellular Signal-Regulated Kinase Induces the Megakaryocyte GPIIb/CD41 Gene through MafB/Kreisler , 2004, Molecular and Cellular Biology.

[29]  N. Rajewsky,et al.  Regulation of the Germinal Center Response by MicroRNA-155 , 2007, Science.

[30]  C. Peschle,et al.  Overexpression of Ets-1 in human hematopoietic progenitor cells blocks erythroid and promotes megakaryocytic differentiation , 2006, Cell Death and Differentiation.

[31]  Thomas Tuschl,et al.  Sequence-specific inhibition of microRNA- and siRNA-induced RNA silencing. , 2004, RNA.

[32]  W. S. Hayward,et al.  Multiple proto-oncogene activations in avian leukosis virus-induced lymphomas: evidence for stage-specific events , 1989, Molecular and cellular biology.

[33]  C. Croce,et al.  MicroRNAs 221 and 222 inhibit normal erythropoiesis and erythroleukemic cell growth via kit receptor down-modulation. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[34]  E. Haralambieva,et al.  Lack of BIC and microRNA miR‐155 expression in primary cases of Burkitt lymphoma , 2006, Genes, chromosomes & cancer.

[35]  C. Lawrie.  MicroRNAs and haematology: small molecules, big function , 2007, British journal of haematology.

[36]  M. Biffoni,et al.  A three-step pathway comprising PLZF/miR-146a/CXCR4 controls megakaryopoiesis , 2008, Nature Cell Biology.

[37]  Shangqin Guo,et al.  MicroRNA-mediated control of cell fate in megakaryocyte-erythrocyte progenitors. , 2008, Developmental cell.

[38]  Alessandro Fatica,et al.  A Minicircuitry Comprised of MicroRNA-223 and Transcription Factors NFI-A and C/EBPα Regulates Human Granulopoiesis , 2005, Cell.

[39]  W. Leonard,et al.  Maturation stage-specific regulation of megakaryopoiesis by pointed-domain Ets proteins. , 2005, Blood.

[40]  C. Y. Chen,et al.  AU-rich elements: characterization and importance in mRNA degradation. , 1995, Trends in biochemical sciences.