RESUMEN
Nuclear and mitochondrial organelles must maintain a communication system. Loci on the mitochondrial genome were recently reported to interact with nuclear loci. To determine whether this is part of a DNA based communication system we used genome conformation capture to map the global network of DNA-DNA interactions between the mitochondrial and nuclear genomes (Mito-nDNA) in Saccharomyces cerevisiae cells grown under three different metabolic conditions. The interactions that form between mitochondrial and nuclear loci are dependent on the metabolic state of the yeast. Moreover, the frequency of specific mitochondrial-nuclear interactions (i.e. COX1-MSY1 and Q0182-RSM7) showed significant reductions in the absence of mitochondrial encoded reverse transcriptase machinery. Furthermore, these reductions correlated with increases in the transcript levels of the nuclear loci (MSY1 and RSM7). We propose that these interactions represent an inter-organelle DNA mediated communication system and that reverse transcription of mitochondrial RNA plays a role in this process.
Asunto(s)
Núcleo Celular/genética , ADN Mitocondrial/genética , Orgánulos/metabolismo , Orgánulos/fisiología , ARN Mensajero/genética , Transcripción Genética , Transporte Biológico/efectos de los fármacos , Transporte Biológico/genética , Transporte Biológico/fisiología , Núcleo Celular/efectos de los fármacos , Cromosomas Fúngicos/efectos de los fármacos , Cromosomas Fúngicos/genética , Cromosomas Fúngicos/metabolismo , Ciclooxigenasa 1/genética , Ciclooxigenasa 1/metabolismo , ADN Mitocondrial/efectos de los fármacos , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Epistasis Genética/efectos de los fármacos , Epistasis Genética/fisiología , Galactosa/farmacología , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Sitios Genéticos/fisiología , Glucosa/farmacología , Orgánulos/efectos de los fármacos , Orgánulos/genética , ARN de Hongos/efectos de los fármacos , ARN de Hongos/genética , ARN de Hongos/metabolismo , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiología , Saccharomyces cerevisiae/ultraestructura , Factores de Tiempo , Transcripción Genética/efectos de los fármacosRESUMEN
Expression data contribute significantly to the biological value of the sequenced human genome, providing extensive information about gene structure and the pattern of gene expression. ESTs, together with SAGE libraries and microarray experiment information, provide a broad and rich view of the transcriptome. However, it is difficult to perform large-scale expression mining of the data generated by these diverse experimental approaches. Not only is the data stored in disparate locations, but there is frequent ambiguity in the meaning of terms used to describe the source of the material used in the experiment. Untangling semantic differences between the data provided by different resources is therefore largely reliant on the domain knowledge of a human expert. We present here eVOC, a system which associates labelled target cDNAs for microarray experiments, or cDNA libraries and their associated transcripts with controlled terms in a set of hierarchical vocabularies. eVOC consists of four orthogonal controlled vocabularies suitable for describing the domains of human gene expression data including Anatomical System, Cell Type, Pathology and Developmental Stage. We have curated and annotated 7016 cDNA libraries represented in dbEST, as well as 104 SAGE libraries,with expression information,and provide this as an integrated, public resource that allows the linking of transcripts and libraries with expression terms. Both the vocabularies and the vocabulary-annotated libraries can be retrieved from http://www.sanbi.ac.za/evoc/. Several groups are involved in developing this resource with the aim of unifying transcript expression information.