title: PLCγ2 and PKC are important to myeloid lineage commitment triggered by M-SCF and G-CSF.
abstract: Myeloid differentiation is a complex process whereby mature granulocytes or monocytes/macrophages are derived from a common myeloid progenitor through the coordinated action of hematopoietic cytokines. In this study, we explored the role of the Ca(2+)i signaling transduction pathway in the commitment of hematopoietic stem/progenitor cells to either the monocytic or granulocytic lineage in response to macrophage colony-stimulating factor (M-CSF) and granulocyte colony-stimulating factor (G-CSF). M-CSF and G-CSF induce cell expansion and monocyte or granulocyte differentiation, respectively, without affecting the percentage of hematopoietic progenitor cells. Colony-forming units (CFUs) and flow cytometry demonstrated the involvement of phospholipase Cγ (PLCγ) and protein kinase C (PKC) in monocyte/granulocyte commitment. In addition, using flow cytometry and RNA interference, we identified PLCγ2 as the PLCγ isoform that participates in this cell expansion and differentiation. Differences in signaling elicited by M-CSF and G-CSF were observed. The M-CSF-related effects were associated with the activation of ERK1/2 and nuclear factor of activated T-cells (NFAT); the inhibition of both molecules reduced the number of colonies in a CFU assay. In contrast, using flow cytometry and confocal evaluation, we demonstrated that G-CSF activated Jak-1 and STAT-3. Additionally, the effects induced by G-CSF were also related with the participation of Ca(2+) calmodulin kinase II and the transcription factor PU.1. STAT-3 activation and the increase of PU.1 expression were sensitive to PLC inhibition by U73122. These data show that PLCγ2 and PKC are important upstream signals that regulate myelopoiesis through cytokines, and differences in M-CSF and G-CSF downstream signaling were identified.
authors.affiliation: Departamento de Biofísica, Universidade Federal de São Paulo, R. Três de Maio, No. 100, 04044-020, São Paulo, SP, Brazil.
authors.forename: Christiano Marcello Vaz
authors.initials: CM
authors.lastname: Barbosa
authors.forename: Claudia
authors.initials: C
authors.lastname: Bincoletto
authors.forename: Carlos Castilho
authors.initials: CC
authors.lastname: Barros
authors.forename: Alice T
authors.initials: AT
authors.lastname: Ferreira
authors.forename: Edgar J
authors.initials: EJ
authors.lastname: Paredes-Gamero
mesh_terms: D000818:Animals; D020013:Calcium Signaling; D002454:Cell Differentiation / Q000187:drug effects; D019070:Cell Lineage / Q000187:drug effects; D003114:Colony-Forming Units Assay; D004963:Estrenes / Q000494:pharmacology; D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism / Q000494:pharmacology*; D006098:Granulocytes / Q000187:drug effects / Q000378:metabolism; D053613:Janus Kinase 1 / Q000378:metabolism; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism; D050778:NFATC Transcription Factors / Q000378:metabolism; D051966:Phospholipase C gamma / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D011760:Pyrrolidinones / Q000494:pharmacology; D034622:RNA Interference; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D004963:Estrenes; D016179:Granulocyte Colony-Stimulating Factor; D053613:Janus Kinase 1; D016173:Macrophage Colony-Stimulating Factor; D050778:NFATC Transcription Factors; D051966:Phospholipase C gamma; D011493:Protein Kinase C; D011518:Proto-Oncogene Proteins; D011760:Pyrrolidinones; D050796:STAT3 Transcription Factor; D015534:Trans-Activators; D000099232:Proto-Oncogene Protein Spi-1; C494087:Stat3 protein, mouse; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; C507905:Jak1 protein, mouse
keywords: CELL SIGNALING; G-CSF; HEMATOPOIETIC STEM/PROGENITOR CELLS; INTRACELLULAR CALCIUM; M-CSF