title: Transduction of static pressure signal to expression of human granurocytes macrophage colony stimulating factor mRNA in Chinese hamster ovary cells.
abstract: The expression level of human granurocytes macrophage colony stimulating factor (hGM-CSF) mRNA in Chinese hamster ovary (CHO) DR1000L4N cells increased by 24% with pressurization. Treatment of cells with chelerythrine chloride (10 nM, 15 min), an inhibitor of protein kinase C (PKC), did not suppress the pressure-induced (0.9 MPa) expression of hGM-CSF mRNA, while it decreased the hGM-CSF gene expression level at normal pressure (0.1 MPa). Treatment with U0126 (20 microM, 60 min), a specific inhibitor of extracellular signal-related kinase (ERK1/2), decreased the expression level of hGM-CSF mRNA at 0.1 MPa to 80% of that without U0126 treatment. Similarly, treatment with U0126 decreased the pressure-induced (0.9 MPa) expression level of hGM-CSF mRNA to 79% of the control expression level at 0.1 MPa without treatment. The amount of intracellular phosphorylated ERK1/2 increased with pressurization (0.9 MPa). These results suggest that the pressure-induced expression of hGM-CSF mRNA in CHO DR1000L4N cells depends not on PKC but on the ERK1/2 signaling cascade.
authors.affiliation: International Center for Biotechnology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Heng
authors.initials: H
authors.lastname: Gong
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Takagi
authors.forename: Toshiomi
authors.initials: T
authors.lastname: Yoshida