Acceleration of granulocyte colony-stimulating factor-induced neutrophilic nuclear lobulation by overexpression of Lyn tyrosine kinase

Tomomi Omura, Hiroshi Sakai, Hiroshi Murakami

Research output: Contribution to journalArticle

6 Citations (Scopus)


Stimulation with granulocyte colony-stimulating factor (G-CSF) induces myeloid precursor cells to differentiate into neutrophils, and tyrosine phosphorylation of certain cellular proteins is crucial to this process. However, the signaling pathways for neutrophil differentiation are still obscure. As the Src-like tyrosine kinase, Lyn, has been reported to play a role in G-CSF-induced proliferation in avian lymphoid cells, we examined its involvement in G-CSF-induced signal transduction in mammalian cells. Expression plasmids for wild-type Lyn (Lyn) and kinase-negative Lyn (LynKN) were introduced into a murine granulocyte precursor cell line, GM-I62M, that can respond to G-CSF with neutrophil differentiation, and cell lines that overexpressed these molecules (GM-Lyn, GM-LynKN) were established. Upon G-CSF stimulation, both the GM-Lyn and GM-LynKN cells began to differentiate into neutrophils, showing early morphological changes within a few days, much more rapidly than did the parental cells, which started to exhibit nuclear lobulation about 10 days after the cells were transferred to G-CSF-containing medium. However, the time course of expression of the myeloperoxidase gene, another neutrophil differentiation marker, was not affected by the overexpression of Lyn or LynKN. Therefore, in normal cells, protein interactions with Lyn, but not its kinase activity, are important for the induction of G-CSF-induced neutrophilic nuclear lobulation in mammalian granulopoiesis.

Original languageEnglish
Pages (from-to)381-389
Number of pages9
JournalEuropean Journal of Biochemistry
Issue number1
Publication statusPublished - Feb 9 2002



  • Differentiation
  • Granulocyte
  • Granulocyte colony-stimulating factor (G-CSF)
  • Lobulation
  • Neutrophil

ASJC Scopus subject areas

  • Biochemistry

Cite this