tailieunhanh - Báo cáo khoa học: Expression of the Drosophila melanogaster ATP synthase a subunit gene is regulated by a transcriptional element containing GAF and Adf-1 binding sites

Mitochondrial biogenesis is a complex and highly regulated process that requires the controlled expression of hundreds of genes encoded in two separated genomes, namely the nuclear and mitochondrial genomes. To identify regulatory proteins involved in the transcriptional control of key nuc-lear-encoded mitochondrial genes, we have performed a detailed analysis of the promoter region of theasubunit of the Drosophila melanogasterF1F0 ATP synthase complex. Using transient transfection assays, we have identified a 56 bpcis-acting proximal regulatory region that contains binding sites for the GAGA factor and the alcohol dehy-drogenase distal factor 1 | Eur. J. Biochem. 271 4003-4013 2004 FEBS 2004 doi Expression of the Drosophila melanogaster ATP synthase a subunit gene is regulated by a transcriptional element containing GAF and Adf-1 binding sites Ana Talamillo1 I Miguel Angel Fernandez-Moreno1 Francisco Martinez-Azorin1 Belen Bornstein1 2 Pilar Ochoa1 and Rafael Garesse1 1 Departamento de Bioquimica Instituto de Investigaciones Biomedicas Alberto Sols CSIC-UAM Facultad de Medicina Universidad Autonoma de Madrid Spain 2Servicio de Bioquimica Hospital Severo Ochoa Leganes Madrid Spain Mitochondrial biogenesis is a complex and highly regulated process that requires the controlled expression of hundreds of genes encoded in two separated genomes namely the nuclear and mitochondrial genomes. To identify regulatory proteins involved in the transcriptional control of key nuc-lear-encoded mitochondrial genes we have performed a detailed analysis of the promoter region of the a subunit of the Drosophila melanogaster F1F0 ATP synthase complex. Using transient transfection assays we have identified a 56 bp cis-acting proximal regulatory region that contains binding sites for the GAGA factor and the alcohol dehydrogenase distal factor 1. In vitro mutagenesis revealed that both sites are functional and phylogenetic footprinting showed that they are conserved in other Drosophila species and in Anopheles gambiae. The 56 bp region has regulatory enhancer properties and strongly activates heterologous promoters in an orientation-independent manner. In addition Northern blot and RT-PCR analysis identified two a-F1-ATPase mRNAs that differ in the length of the 3 untranslated region due to the selection of alternative polyadenylation sites. Keywords mitochondria a-F1-ATPase GAGA Adf-1 transcription regulation. The bulk of cellular ATP is synthesized through oxidative phosphorylation OXPHOS that takes place in the mitochondria. The OXPHOS system is composed of five multisubunit complexes embedded in