E2F-1 and a cyclin-like DNA repair enzyme, uracil-DNA glycosylase, provide evidence for an autoregulatory mechanism for transcription.
The cell cycle-dependent transcription factor, E2F-1, regulates the cyclin-like species of the DNA repair enzyme uracil-DNA glycosylase (UDG) gene in human osteosarcoma (Saos-2) cells. We demonstrate, through the deletion of the human UDG promoter sequences, that expression of E2F-1 activates the UDG promoter through several E2F sites. The major putative downstream site for E2F, located in the first exon, serves as a target for E2F-1/DP1 complex binding in vitro. We also provide evidence for the functional relationship between the cyclin-like UDG gene product and E2F. High levels of UDG expression in a transient transfection assay result in the down-regulation of transcriptional activity through elements specific for E2F-mediated transcription. Overexpression of UDG in Saos 2 cells was observed to delay growth late in G1 phase and transiently arrest these cells from progressing into the S phase. This hypothetical model integrates one mechanism of DNA repair with the cell cycle control of gene transcription, likely through E2F. This implicates E2F as a multifunctional target for proteins and enzymes, possibly, responsive to DNA damage through the negative effect of UDG on E2F-mediated transcriptional activity.
Walsh
M J
MJ
Department of Pediatrics, Mount Sinai School of Medicine, New York, New York 10029.
Shue
G
G
Spidoni
K
K
Kapoor
A
A
D015703:Antigens, CD / Q000096:biosynthesis; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte / Q000096:biosynthesis; D001402:B-Lymphocytes / Q000276:immunology; D001483:Base Sequence; D001859:Bone Neoplasms; D002352:Carrier Proteins; D002453:Cell Cycle; D018797:Cell Cycle Proteins; D002455:Cell Division; D002460:Cell Line; D015500:Chloramphenicol O-Acetyltransferase / Q000096:biosynthesis; D045647:DNA Glycosylases; D017931:DNA Primers; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; D005434:Flow Cytometry; D016193:G1 Phase; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006706:Homeostasis; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009699:N-Glycosyl Hydrolases / Q000096:biosynthesis*; D012516:Osteosarcoma; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000096:biosynthesis; D015183:Restriction Mapping; D056465:Retinoblastoma-Binding Protein 1; D016196:S Phase; D050680:Transcription Factor DP1; D014157:Transcription Factors / Q000096:biosynthesis / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured; D051981:Uracil-DNA Glycosidase
D015703:Antigens, CD; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; D011994:Recombinant Proteins; D056465:Retinoblastoma-Binding Protein 1; C493735:TFDP1 protein, human; D050680:Transcription Factor DP1; D014157:Transcription Factors; D015500:Chloramphenicol O-Acetyltransferase; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; D051981:Uracil-DNA Glycosidase