title: Granulocyte colony-stimulating factor promotes the translocation of protein kinase Ciota in neutrophilic differentiation cells.
abstract: Previously, we suggested that the phosphatidylinositol 3-kinase (PI3K)-p70 S6 kinase (p70 S6K) pathway plays an important role in granulocyte colony-stimulating factor (G-CSF)-dependent enhancement of the neutrophilic differentiation and proliferation of HL-60 cells. While atypical protein kinase C (PKC) has been reported to be a regulator of p70 S6K, abundant expression of PKCiota was observed in myeloid and lymphoid cells. Therefore, we analyzed the participation of PKCiota in G-CSF-dependent proliferation. The maximum stimulation of PKCiota was observed from 15 to 30 min after the addition of G-CSF. From 5 to 15 min into this lag time, PKCiota was found to translocate from the nucleus to the membrane. At 30 min it re-translocated to the cytosol. This dynamic translocation of PKCiota was also observed in G-CSF-stimulated myeloperoxidase-positive cells differentiated from cord blood cells. Small interfering RNA for PKCiota inhibited G-CSF-induced proliferation and the promotion of neutrophilic differentiation of HL-60 cells. These data indicate that the G-CSF-induced dynamic translocation and activation processes of PKCiota are important to neutrophilic proliferation.
authors.affiliation: Division of Cellular and Gene Therapy Products, National Institute of Health Sciences, Tokyo, Japan.
authors.forename: Toshie
authors.initials: T
authors.lastname: Kanayasu-Toyoda
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Tadashi
authors.initials: T
authors.lastname: Oshizawa
authors.forename: Eriko
authors.initials: E
authors.lastname: Uchida
authors.forename: Takao
authors.initials: T
authors.lastname: Hayakawa
authors.forename: Teruhide
authors.initials: T
authors.lastname: Yamaguchi
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D020869:Gene Expression Profiling; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D018922:HL-60 Cells; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D019169:Jurkat Cells; D020014:K562 Cells; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D010766:Phosphorylation / Q000187:drug effects; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D034741:RNA, Small Interfering / Q000378:metabolism; D011990:Receptors, Transferrin / Q000378:metabolism; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D013347:Subcellular Fractions / Q000187:drug effects / Q000201:enzymology; D013997:Time Factors; D000099293:Protein Kinase C-lambda; D000099221:Protein Kinase C zeta
chemical_list: D016179:Granulocyte Colony-Stimulating Factor; D007527:Isoenzymes; D011493:Protein Kinase C; D034741:RNA, Small Interfering; D011990:Receptors, Transferrin; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D000099293:Protein Kinase C-lambda; D000099221:Protein Kinase C zeta