title: Activation of human monoamine oxidase B gene expression by a protein kinase C MAPK signal transduction pathway involves c-Jun and Egr-1.
abstract: Monoamine oxidases (MAO) A and B deaminate a number of biogenic amines. Aberrant expression of MAO is implicated in several psychiatric and neurogenerative disorders. In this study, we have shown that phorbol 12-myristate 13-acetate (PMA) increases human MAO B, but not MAO A, gene expression. The sequence between -246 and -225 bp consists of overlapping binding sites (Sp1/Egr-1/Sp1) that are recognized by Sp1, Sp3, and PMA-inducible Egr-1 is essential for PMA activation. PMA transiently increases egr-1 and c-jun gene expression. Mutation studies show that Egr-1 and c-Jun transactivate the MAO B promoter and increase endogenous MAO B transcripts via the Sp1/Egr-1/Sp1 overlapping binding sites. Sp3 inhibits Sp1 and Egr-1 activation of MAO B gene expression. c-fos gene expression was increased by PMA but not involved in MAO B gene transcription. Furthermore, protein kinase C inhibitor blocks the PMA-dependent activation of MAO B. Co-transfection of the MAO B promoter with dominant negative forms of Ras, Raf-1, MEKK1, MEK1, MEK3, MEK7, ERK2, JNK1, and p38/RK inhibit the PMA-dependent activation of the MAO B promoter. These results indicate that MAO B expression is selectively induced by the activation of protein kinase C and MAPK signaling pathway and that c-Jun and Egr-1 appear to be the ultimate targets of this regulation.
authors.affiliation: Department of Molecular Pharmacology and Toxicology, School of Pharmacy, University of Southern California, Los Angeles, California 90089-9121, USA.
authors.forename: Wai K
authors.initials: WK
authors.lastname: Wong
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Ou
authors.forename: Kevin
authors.initials: K
authors.lastname: Chen
authors.forename: Jean C
authors.initials: JC
authors.lastname: Shih
mesh_terms: D001665:Binding Sites; D015152:Blotting, Northern; D015153:Blotting, Western; D002384:Catalysis; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D051766:Early Growth Response Protein 1; D004789:Enzyme Activation; D017353:Gene Deletion; D005786:Gene Expression Regulation; D015971:Gene Expression Regulation, Enzymologic; D005799:Genes, Dominant; D017930:Genes, Reporter; D005822:Genetic Vectors; D006801:Humans; D017874:Immediate-Early Proteins; D008156:Luciferases / Q000378:metabolism; D020935:MAP Kinase Signaling System; D008995:Monoamine Oxidase / Q000235:genetics* / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011493:Protein Kinase C / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism*; D015398:Signal Transduction; D016329:Sp1 Transcription Factor / Q000378:metabolism; D051705:Sp3 Transcription Factor; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism*; D014162:Transfection
chemical_list: D004268:DNA-Binding Proteins; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; D017874:Immediate-Early Proteins; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; C497121:SP3 protein, human; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D051705:Sp3 Transcription Factor; D008156:Luciferases; D008995:Monoamine Oxidase; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate