title: Ras-Raf-Arf signaling critically depends on the Dmp1 transcription factor.
abstract: Dmp1 prevents tumor formation by activating the Arf-p53 pathway. In cultured primary cells, the Dmp1 promoter was efficiently activated by oncogenic Ha-Ras(V12), but not by overexpressed c-Myc or E2F-1. Dmp1 promoter activation by Ras(V12) depended on Raf-MEK-ERK signaling. Induction of p19(Arf) and p21(Cip1) by oncogenic Raf was compromised in Dmp1-null cells, which were resistant to Raf-mediated premature senescence. A Ras(V12)-responsive element was mapped to the 5' leader sequence of the murine Dmp1 promoter, where endogenous Fos and Jun family proteins bind. Dmp1 promoter activation by Ras(V12) was strikingly impaired in c-Jun as well as in JunB knock-down cells, suggesting the critical role of Jun proteins in the activation of the Dmp1 promoter. A Ras(V12)-responsive element was mapped to the unique Dmp1/Ets site on the Arf promoter, where endogenous Dmp1 proteins bind upon oncogenic Raf activation. Therefore, activation of Arf by Ras/Raf signaling is indirectly mediated by Dmp1, explaining why Dmp1-null primary cells are highly susceptible to Ras-induced transformation. Our data indicate the presence of the novel Jun-Dmp1 pathway that directly links oncogenic Ras-Raf signaling and p19(Arf), independent of the classical cyclin D1/Cdk4-Rb-E2F pathway.
authors.affiliation: Department of Pathology, Wake Forest University Health Sciences, 2102 Gray Building, Medical Center Blvd., Winston-Salem, NC 27157, USA.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Sreeramaneni
authors.forename: Asif
authors.initials: A
authors.lastname: Chaudhry
authors.forename: Martin
authors.initials: M
authors.lastname: McMahon
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Sherr
authors.forename: Kazushi
authors.initials: K
authors.lastname: Inoue
mesh_terms: D020823:ADP-Ribosylation Factor 1 / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000378:metabolism; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D016922:Cellular Senescence; D047369:Chromatin Immunoprecipitation; D003001:Cloning, Molecular; D050759:Cyclin-Dependent Kinase Inhibitor p21; D004247:DNA / Q000378:metabolism; D017930:Genes, Reporter; D005822:Genetic Vectors; D051379:Mice; D008807:Mice, Inbred BALB C; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D008954:Models, Biological; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D041681:NIH 3T3 Cells; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D020218:Response Elements; D012190:Retroviridae / Q000235:genetics; D015398:Signal Transduction; D013997:Time Factors; D014157:Transcription Factors / Q000502:physiology*; D048490:raf Kinases / Q000378:metabolism*; D018631:ras Proteins / Q000378:metabolism*
chemical_list: C493957:Cdkn1a protein, mouse; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; C491126:DMTF1 protein, human; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D034741:RNA, Small Interfering; D014157:Transcription Factors; D004247:DNA; D048490:raf Kinases; D048052:Mitogen-Activated Protein Kinase 3; D020823:ADP-Ribosylation Factor 1; D018631:ras Proteins