Project description:Mitochondrial DNA (mtDNA) in budding yeast is biparentally inherited, but colonies rapidly lose one type of parental mtDNA, becoming homoplasmic. Therefore, hybrids between different yeast species possess two homologous nuclear genomes, but only one type of mitochondrial DNA. We hypothesise that the choice of mtDNA retention is influenced by its contribution to hybrid fitness in different environments, and that the allelic expression of the two nuclear sub-genomes is affected by the presence of different mtDNAs in hybrids. Here, we crossed Saccharomyces cerevisiae with S. uvarum under different environmental conditions and examined the plasticity of the retention of mtDNA in each hybrid.
Project description:Mitochondrial DNA (mtDNA) in budding yeast is biparentally inherited, but colonies rapidly lose one type of parental mtDNA, becoming homoplasmic. Therefore, hybrids between different yeast species possess two homologous nuclear genomes, but only one type of mitochondrial DNA. We hypothesise that the choice of mtDNA retention is influenced by its contribution to hybrid fitness in different environments, and that the allelic expression of the two nuclear sub-genomes is affected by the presence of different mtDNAs in hybrids. Here, we crossed Saccharomyces cerevisiae with S. uvarum under different environmental conditions and examined the plasticity of the retention of mtDNA in each hybrid.
Project description:BACKGROUND: The tomato psyllid, Bactericera cockerelli Šulc (Hemiptera: Triozidae), is a pest of solanaceous crops such as tomato (Solanum lycopersicum L.) in the U.S. and vectors the disease-causing pathogen ‘Candidatus Liberibacter solanacearum’. Currently, the only effective strategies for controlling the diseases associated with this pathogen involve regular pesticide applications to manage psyllid population density. However, such practices are unsustainable and will eventually lead to widespread pesticide resistance in psyllids. Therefore, new control strategies must be developed to increase host-plant resistance to insect vectors. For example, expression of constitutive and inducible plant defenses can be improved through selection. Currently, it is still unknown whether psyllid infestation has any lasting consequences on tomato plant defense or tomato plant gene expression in general. RESULTS: To characterize the genes putatively involved in tomato defense against psyllid infestation, RNA was extracted from psyllid-infested and uninfested tomato leaves (Moneymaker) three weeks post-infestation. Transcriptome analysis identified 362 differentially expressed genes. These differentially expressed genes were primarily associated with defense responses to abiotic/biotic stress, transcription/translation, cellular signaling/transport, and photosynthesis. These gene expression changes suggested that tomato plants underwent a reduction in plant growth/health in exchange for improved defense against stress that was observable three weeks after psyllid infestation. Consistent with these observations, tomato plant growth experiments determined that the plants were shorter three weeks after psyllid infestation. Furthermore, psyllid nymphs had lower survival rates on tomato plants that had been previously psyllid infested. CONCLUSION: These results suggested that psyllid infestation has lasting consequences for tomato gene expression, defense, and growth.
Project description:ChIP-seq data characterizing the occupancy of TFAM over the mitochondrial and nuclear genomes in HeLa cells. Characterization of mitochondrial and nuclear genome-wide TFAM binding in HeLa cells