Positive and negative regulation of granulocyte-macrophage colony-stimulating factor promoter activity by AML1-related transcription factor, PEBP2.
The granulocyte-macrophage colony-stimulating factor (GM-CSF) gene promoter contains a consensus sequence for the polyomavirus enhancer binding-protein 2 (PEBP2) transcription factor, which consists of alpha and beta subunits. There are at least two genes, alpha A and alpha B, encoding the alpha subunit. alpha B is the mouse homologue of human AML1 gene detected at the breakpoints of t(8;21) and t(3;21) myeloid leukemias. We examined alpha A1 (an alpha A-gene product) and alpha B1 and alpha B2 (two alpha B-encoded isomers) for their effects on the GM-CSF promoter. PEBP2 alpha A1, alpha B1, and alpha B2 proteins bound the PEBP2 site within the mouse GM-CSF promoter. PEBP2 alpha A1 and alpha B1 enhanced the expression of the GM-CSF promoter-driven reporter plasmid in unstimulated and 12-O-tetradecanoylphorbol 13-acetate/phytohemagglutinin-stimulated human Jurkat T cells. In contrast, the promoter activity was suppressed by alpha B2. Coexpression of alpha B1 and alpha B2 showed that the promoter activity could be determined by the alpha B1/alpha B2 ratio. Jurkat cell extract contained PEBP2 site-binding protein(s) that cross-reacted with antimouse alpha A1 antibodies. Northern blot analysis indicated the expression of human PEBP2 alpha A, alpha B (AML1), and beta genes in Jurkat cells. Although further studies are required to determine the precise role of PEBP2 in the GM-CSF promoter activity, the present findings suggested the importance of the relative ratio of different PEBP2 isoforms in regulating the levels of the promoter activity.
Takahashi
A
A
Department of Viral Oncology, Kyoto University, Japan.
Satake
M
M
Yamaguchi-Iwai
Y
Y
Bae
S C
SC
Lu
J
J
Maruyama
M
M
Zhang
Y W
YW
Oka
H
H
Arai
N
N
Arai
K
K
D000818:Animals; D001483:Base Sequence; D018236:Carcinoma, Embryonal / Q000473:pathology; D016384:Consensus Sequence; D050659:Core Binding Factor Alpha 1 Subunit; D050676:Core Binding Factor Alpha 2 Subunit; D050657:Core Binding Factor alpha Subunits; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation / Q000187:drug effects; D017930:Genes, Reporter; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000235:genetics*; D006801:Humans; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000473:pathology; D008213:Lymphocyte Activation; D051379:Mice; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics*; D010835:Phytohemagglutinins / Q000494:pharmacology; D011120:Polyomavirus / Q000235:genetics; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins; D016415:Sequence Alignment; D013045:Species Specificity; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000235:genetics* / Q000502:physiology*; D014158:Transcription, Genetic / Q000187:drug effects; D014407:Tumor Cells, Cultured
D050659:Core Binding Factor Alpha 1 Subunit; D050676:Core Binding Factor Alpha 2 Subunit; D050657:Core Binding Factor alpha Subunits; D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; D010835:Phytohemagglutinins; D011518:Proto-Oncogene Proteins; C493728:RUNX1 protein, human; C493726:Runx1 protein, mouse; C493716:Runx2 protein, mouse; D050656:Transcription Factor AP-2; D014157:Transcription Factors; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013755:Tetradecanoylphorbol Acetate