Molecular cloning and characterization of G-CSF induced gene cDNA.

G-CSF (granulocyte colony-stimulating factor) is known to specifically stimulate the production and the functional activation of neutrophils. To investigate the intracellular signaling pathway of myeloid cells stimulated by G-CSF, we isolated new genes whose expression was induced by G-CSF. First of all, we constructed lambda gt10 cDNA library from G-CSF-stimulated mononuclear cells (MNC) of a chronic myelogenous leukemia (CML) patient (CML-MNC) and screened the cDNA library by a differential hybridization method. The 24 candidate clones which specifically hybridized with G-CSF-stimulated CML-MNC cDNA probes, but not with unstimulated CML-MNC cDNA probes, were obtained after 8 x 10(4) individual clones had been screened. One of these clones, GIG-1 (G-CSF-induced gene-1), was further characterized. The size of the GIG-1 mRNA was about 0.9kb. The GIG-1 mRNA was expressed mainly in the myeloid leukemic cell lines.