Project description: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. Genome Conformation Capture (GCC) has been performed on exponentially growing Saccharomyces cerevisiae cultures in glucose containing media. Paired end sequencing on an Illumina Genome Analyser was performed before the sequences were analysed by the propieatry software Topography 1.19. Inter- and intra- chromosomal interactions were mapped onto the S. cerevisiae S288 genome scaffold.
Project description: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. Genome Conformation Capture (GCC) has been performed on exponentially growing Saccharomyces cerevisiae cultures in glycerol lactate or galactose media. Paired end sequencing on an Illumina Genome Analyser was performed before the sequences were analysed by the propieatry software Topography 1.19. Inter- and intra- chromosomal interactions were mapped onto the S. cerevisiae S288 genome scaffold.
Project description: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.
Project description:Here we report that the spatial organization of yeast tRNA genes depends upon both locus position and tRNA identity; supporting the idea that the genomic organization of tRNA loci utilizes tRNA dependent signals within the nucleoprotein-tRNA complexes that form into clusters. We use high-throughput sequencing coupled to Circular Chromosome Conformation Capture to detect interactions with two wild type tRNAs and these same positions replaced with suppressor tRNAs (SUP4-1). Detect DNA-DNA interactions (Circular chromosome conformation capture; 4C) with two wild type tRNAs and these same positions replaced with suppressor tRNAs (SUP4-1) Supplementary files: Alignment files generated by Topography v1.19 software.
Project description: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.
Project description:Development of molecular approaches based on chromosome conformation capture (3C) technology such as Hi-C, combined with methods for modeling and interpreting chromatin interaction data, have revolutionized the analysis of chromosome folding. Even if the impact of chromatin structure on gene expression seems likely, little is known about the dynamics of DNA compaction and the factors involved in this process still have to be determined. Using the yeast Saccharomyces cerevisiae as a model, we used Hi-C technology to evaluate how 3D chromatin structure changes during different cellular processes such as adaptation in response to stress or DNA repair. We optimized the protocol from Belton, J.M et al (1) to produce our Hi-C libraries, one from control cells, one from cells after oxidative stress and one from cells after UV irradiation. Preliminary analysis suggests that in response to oxidative stress, chromosomes tend to make more contacts in trans and less contacts in cis compared to normal condition.
Project description:The objective of this study was to determine the global chromosomal interaction map for exponentially growing Saccharomyces cerevisiae cells using Genome Conformation Capture. Interactions between chromosomes were identified within a population of yeast cells growing exponentially in a semi-defined medium containing glucose. The series contains the sequences of the ligated restriction fragments that identified the interactions.