miRNA-130a regulates C/EBP-ε expression during granulopoiesis

Blood. 2014 Feb 13;123(7):1079-89. doi: 10.1182/blood-2013-08-523233. Epub 2014 Jan 7.

Abstract

CCAAT/enhancer binding protein-ε (C/EBP-ε) is considered a master transcription factor regulating terminal neutrophil maturation. It is essential for expression of secondary granule proteins, but it also regulates proliferation, cell cycle, and maturation during granulopoiesis. Cebpe(-/-) mice have incomplete granulocytic differentiation and increased sensitivity toward bacterial infections. The amount of C/EBP-ε messenger RNA (mRNA) increases with maturation from myeloblasts with peak level in myelocytes (MC)/metamyelocytes (MM), when the cells stop proliferating followed by a decline in more mature cells. In contrast, C/EBP-ε protein is virtually detectable only in the MC/MM population, indicating that expression in more immature cells could be inhibited by microRNAs (miRNAs). We found that miRNA-130a (miR-130a) regulates C/EBP-ε protein expression in both murine and human granulocytic precursors. Overexpression of miR-130a in a murine cell line downregulated C/EBP-ε protein and lactoferrin (Ltf), cathelicidin antimicrobial protein (Camp), and lipocalin-2 (Lcn2) mRNA expression giving rise to cells with a more immature phenotype, as seen in the Cebpe(-/-) mouse. Introduction of a C/EBP-ε mRNA without target site for miR-130a restored both C/EBP-ε production, expression of Camp and Lcn2, and resulted in the cells having a more mature phenotype. We conclude that miR-130a is important for the regulation of the timed expression of C/EBP-ε during granulopoiesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CCAAT-Enhancer-Binding Proteins / genetics*
  • Cell Differentiation / genetics
  • Cells, Cultured
  • Gene Expression Regulation
  • Granulocyte Precursor Cells / physiology
  • Granulocytes / physiology*
  • HEK293 Cells
  • Humans
  • Leukopoiesis / genetics*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • MicroRNAs / physiology*
  • NIH 3T3 Cells

Substances

  • CCAAT-Enhancer-Binding Proteins
  • MIRN130 microRNA, human
  • MicroRNAs
  • CEBPE protein, human