YY1 and Sp1 activate transcription of the human NDUFS8 gene encoding the mitochondrial complex I TYKY subunit.
Complex I is the most complicated of the multimeric enzymes that constitute the mitochondrial respiratory chain. It is encoded by both mitochondrial and nuclear genomes. We have previously characterized the human NDUFS8 gene that encodes the TYKY subunit. This essential subunit is thought to participate in the electron transfer and proton pumping activities of complex I. Here, we have analyzed the transcriptional regulation of the NDUFS8 gene. Using primer extension assays, we have identified two transcription start sites. The basal promoter was mapped to a 247 bp sequence upstream from the main transcription start site by reporter gene analysis in HeLa cells and in differentiated or non-differentiated C2C12 cells. Three Sp1 sites and one YY1 site were identified in this minimal promoter. Through gel shift analysis, all sites were shown to bind to their cognate transcription factors. Site-directed mutagenesis revealed that the YY1 site and two upstream adjacent Sp1 sites drive most of the promoter activity. This work represents the first promoter analysis for a complex I gene. Together with previous studies, our results indicate that YY1 and Sp1 control the expression of genes encoding proteins that are involved in almost all steps of the oxidative phosphorylation metabolism.
Lescuyer
Pierre
P
Laboratoire BECP-EA2943 UJF/LRA6V CEA-DBMS, CEA Grenoble, 17 rue des Martyrs, 38054 Cedex 9, Grenoble, France. plescuyer@cea.fr
Martinez
Pascal
P
Lunardi
Joël
J
D001483:Base Sequence; D001665:Binding Sites; D024202:Electrophoretic Mobility Shift Assay; D050981:Erythroid-Specific DNA-Binding Factors; D005091:Exons; D005786:Gene Expression Regulation; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000235:genetics* / Q000378:metabolism; D009245:NADH Dehydrogenase; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014162:Transfection; D050986:YY1 Transcription Factor
D050981:Erythroid-Specific DNA-Binding Factors; C113982:NDUFS8 protein, human; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C494698:YY1 protein, human; D016660:NAD(P)H Dehydrogenase (Quinone); D009245:NADH Dehydrogenase