G-CSF induces tyrosine phosphorylation of the JAK2 protein in the human myeloid G-CSF responsive and proliferative cells, but not in mature neutrophils.
Granulocyte colony-stimulating factor (G-CSF) stimulates a rapid phosphorylation on tyrosines of several proteins of Mr. 130, 100, 90, 70, 44 kd in human myeloid leukemia cell line cells, Kasumi-1, which respond to G-CSF to proliferate in vitro. In HL60 cells, only a 100 kd protein was phosphorylated, and no detectable phosphorylated proteins were observed in neutrophils by the stimulation of G-CSF. Among these proteins, the 130 kd protein was immunoprecipitated by anti- JAK2 serum. While JAK2 is a non receptor tyrosine kinase and is reported to be involved in the signal transduction by various cytokines including growth hormone, erythropoietin, and granulocyte-macrophage colony-stimulating factor/interleukin-3, it is strongly suggested that a signaling pathway that relates to the cell proliferation triggered by G-CSF in immature hematopoietic cells also involves JAK2.
Shimoda
K
K
First Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Iwasaki
H
H
Okamura
S
S
Ohno
Y
Y
Kubota
A
A
Arima
F
F
Otsuka
T
T
Niho
Y
Y
D002455:Cell Division; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D007163:Immunosorbent Techniques; D053614:Janus Kinase 2; D007700:Kinetics; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism* / Q000473:pathology; D009504:Neutrophils / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism
D011518:Proto-Oncogene Proteins; D016179:Granulocyte Colony-Stimulating Factor; D019000:Phosphotyrosine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; D053614:Janus Kinase 2