Transcriptional regulation of the Drosophila catalase gene by the DRE/DREF system.
Reactive oxygen species (ROS) cause oxidative stress and aging. The catalase gene is a key component of the cellular antioxidant defense network. However, the molecular mechanisms that regulate catalase gene expression are poorly understood. In this study, we have identified a DNA replication-related element (DRE; 5'-TATCGATA) in the 5'-flanking region of the Drosophila catalase gene. Gel mobility shift assays revealed that a previously identified factor called DREF (DRE- binding factor) binds to the DRE sequence in the Drosophila catalase gene. We used site-directed mutagenesis and in vitro transient transfection assays to establish that expression of the catalase gene is regulated by DREF through the DRE site. To explore the role of DRE/DREF in vivo, we established transgenic flies carrying a catalase-lacZ fusion gene with or without mutation in the DRE. The beta-galactosidase expression patterns of these reporter transgenic lines demonstrated that the catalase gene is upregulated by DREF through the DRE sequence. In addition, we observed suppression of the ectopic DREF-induced rough eye phenotype by a catalase amorphic Cat(n1) allele, indicating that DREF activity is modulated by the intracellular redox state. These results indicate that the DRE/DREF system is a key regulator of catalase gene expression and provide evidence of cross-talk between the DRE/DREF system and the antioxidant defense system.
Department of Molecular Biology, Pusan National University, Busan 609-735, Korea.
So Young
SY
Park
Young-Shin
YS
Kim
Dong-Jin
DJ
Yang
Mi-Ae
MA
Yoo
D024506:5' Flanking Region; D000818:Animals; D001665:Binding Sites; D002374:Catalase / Q000235:genetics*; D004330:Drosophila / Q000033:anatomy & histology / Q000201:enzymology / Q000235:genetics*; D029721:Drosophila Proteins; D005123:Eye / Q000033:anatomy & histology; D015971:Gene Expression Regulation, Enzymologic; D017344:Genes, Insect; D009154:Mutation; D010641:Phenotype; D020218:Response Elements; D014157:Transcription Factors / Q000502:physiology*; D015533:Transcriptional Activation
C099494:Dref protein, Drosophila; D029721:Drosophila Proteins; D014157:Transcription Factors; D002374:Catalase