title: Platelet-derived growth factor up-regulates the expression of transcription factors NF-E2, GATA-1 and c-Fos in megakaryocytic cell lines.
abstract: Platelet-derived growth factor (PDGF) is a platelet alpha-granule protein. In previous reports, we demonstrated the expression of PDGF receptors on platelets and megakaryocytic cells and that PDGF enhanced the proliferation of megakaryocytic progenitor cells. In this study, we investigated the effects of PDGF on mRNA and protein expressions of megakaryocyte-associated transcription factors, c-Fos, GATA-1, NF-E2 and PU.1, in two human megakaryocytic cell lines CHRF-288-11 and DAMI. RT-PCR/Southern blot analysis and Real-time PCR demonstrated that PDGF increased the mRNA expression of c-Fos, GATA-1 and NF-E2, but not PU.1 in a dose- and time-dependent manner. The activation was confirmed at the protein level by Western blot analysis of both total cell and nuclear lysates. The addition of increasing concentrations of Tyrphostin AG1295, an inhibitor of PDGF receptor kinase, blocked the stimulatory effect of PDGF on the mRNA and protein expressions of these transcription factors. The up-regulation of c-Fos, GATA-1 and NF-E2 protein by PDGF was inhibited by actinomycin D and cycloheximide, suggesting that mRNA and protein synthesis might be involved in the mechanism. Our data suggest a direct stimulatory effect of PDGF on c-Fos, GATA-1 and NF-E2 expressions and we speculate that these transcription factors might be involved in the signal transduction of PDGF on the regulation of megakaryocytopoiesis.
authors.affiliation: Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, 6th Floor, Clinical Sciences Building, Shatin, N T, Hong Kong, People's Republic of China.
authors.forename: Cecilia Mei Yan
authors.initials: CM
authors.lastname: Chui
authors.forename: Karen
authors.initials: K
authors.lastname: Li
authors.forename: Mo
authors.initials: M
authors.lastname: Yang
authors.forename: Carmen Ka Yee
authors.initials: CK
authors.lastname: Chuen
authors.forename: Tai Fai
authors.initials: TF
authors.lastname: Fok
authors.forename: Chi Kong
authors.initials: CK
authors.lastname: Li
authors.forename: Patrick Man Pan
authors.initials: PM
authors.lastname: Yuen
mesh_terms: D015139:Blotting, Southern; D015153:Blotting, Western; D002455:Cell Division; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D003609:Dactinomycin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D006801:Humans; D008533:Megakaryocytes / Q000378:metabolism*; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; D010982:Platelet-Derived Growth Factor / Q000378:metabolism / Q000502:physiology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013997:Time Factors; D015534:Trans-Activators / Q000096:biosynthesis; D014157:Transcription Factors / Q000096:biosynthesis*; D020032:Tyrphostins / Q000494:pharmacology; D015854:Up-Regulation; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D003513:Cycloheximide; D004268:DNA-Binding Proteins; D003609:Dactinomycin; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; D010982:Platelet-Derived Growth Factor; D011500:Protein Synthesis Inhibitors; D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D015534:Trans-Activators; D014157:Transcription Factors; D020032:Tyrphostins; D000099232:Proto-Oncogene Protein Spi-1; C407689:6,7-dimethoxy-2-phenylquinoxaline; C494688:GATA1 protein, human; C494692:NFE2 protein, human