Genome and transcriptome divergence in Bacillus subtilis after 6,000 generations of evolution
Ontology highlight
ABSTRACT:
ORGANISM(S): Bacillus subtilis
PROVIDER: GSE4469 | GEO | 2008/01/01
SECONDARY ACCESSION(S): PRJNA94539
REPOSITORIES: GEO
Similar Datasets
Project description:Ten populations were evolved for 6,000 generations. Five had strong selection for sporulation, imposed partially by their cultivation in sporulation-inducing medium, while the other five populations had relaxed selection for sporulation, by cultivating them in sporulation-repressing medium. Batch cultures were diluted 1:100 daily for approximately 892 days. In the five populations with relaxed selection for sporulation, sporulation ability was eventually lost. Keywords: comparative genome hybridization and transcriptome divergence Genomic DNA from all ten populations, and ancestors, was isolated, labeled and hybridized to microarrays. Only one hybridization was performed for each experimental population, with evolved and ancestral DNA hybridized to the slide. RNA hybridizations were done by chosing one strain that was evolved in sporulation-repressing medium and one strain that was evolved in sporulation-inducing medium. Two biological replicates were performed, as well as a dye swap for each biological replicate. Evolved and ancestral strains were grown in identical medium and RNA was isolated at the onset of stationary phase.
2010-06-30 | E-GEOD-4469 | biostudies-arrayexpress
Project description:Five batch cultures of Bacillus subtilis were subjected to laboratory evolution for 6,000 generations under conditions repressing sporulation in complex liquid medium containing glucose. Between 1,000 and 2,000 generations, variants with a distinct small-colony morphology arose and swept through four of the five populations. To understand the nature of adaptation in these variants, individual strains were isolated from one population before (WN715) and after (WN716) the sweep. In addition to colony morphology, strains WN715 and WN716 differed in their motility, aerotaxis, and cell morphology. Competition experiments of WN715 vs. WN716 showed that WN716 had gained a distinct fitness advantage during growth and the transition to stationary phase, which was more pronounced when WN715 was present in co-culture. Microarray analyses revealed candidate genes in which mutations may have produced some of the observed phenotypes.
2010-09-09 | GSE24018 | GEO
Project description:Five batch cultures of Bacillus subtilis were subjected to laboratory evolution for 6,000 generations under conditions repressing sporulation in complex liquid medium containing glucose. Between 1,000 and 2,000 generations, variants with a distinct small-colony morphology arose and swept through four of the five populations. To understand the nature of adaptation in these variants, individual strains were isolated from one population before (WN715) and after (WN716) the sweep. In addition to colony morphology, strains WN715 and WN716 differed in their motility, aerotaxis, and cell morphology. Competition experiments of WN715 vs. WN716 showed that WN716 had gained a distinct fitness advantage during growth and the transition to stationary phase, which was more pronounced when WN715 was present in co-culture. Microarray analyses revealed candidate genes in which mutations may have produced some of the observed phenotypes. One condition tested; 1 biological rep; 2 strains
2010-09-09 | E-GEOD-24018 | biostudies-arrayexpress
Project description:Ray2013 - S.cerevisiae meiosis-specific metabolic network
Meiosis is a strongly concerved cell division program that generates haploid gametes from a diploid parental cell. Successful meiosis is the fundamental basis of sexual reproduction. Multiple lines of evidence suggest a tight link between meiosis and metabolism. Here, yeast meiosis is studied to elucidate the link between reproduction and metabolism. Network flux is obtained using GLPK (GNU Linear Programming Kit) supported by the COBRA Toolbox for Matlab.
This model is described in the article:
Characterization of the metabolic requirements in yeast meiosis.
Ray D, Ye P.
PLoS One. 2013 May 8;8(5):e63707.
Abstract:
The diploid yeast Saccharomyces cerevisiae undergoes mitosis in glucose-rich medium but enters meiosis in acetate sporulation medium. The transition from mitosis to meiosis involves a remarkable adaptation of the metabolic machinery to the changing environment to meet new energy and biosynthesis requirements. Biochemical studies indicate that five metabolic pathways are active at different stages of sporulation: glutamate formation, tricarboxylic acid cycle, glyoxylate cycle, gluconeogenesis, and glycogenolysis. A dynamic synthesis of macromolecules, including nucleotides, amino acids, and lipids, is also observed. However, the metabolic requirements of sporulating cells are poorly understood. In this study, we apply flux balance analyses to uncover optimal principles driving the operation of metabolic networks over the entire period of sporulation. A meiosis-specific metabolic network is constructed, and flux distribution is simulated using ten objective functions combined with time-course expression-based reaction constraints. By systematically evaluating the correlation between computational and experimental fluxes on pathways and macromolecule syntheses, the metabolic requirements of cells are determined: sporulation requires maximization of ATP production and macromolecule syntheses in the early phase followed by maximization of carbohydrate breakdown and minimization of ATP production in the middle and late stages. Our computational models are validated by in silico deletion of enzymes known to be essential for sporulation. Finally, the models are used to predict novel metabolic genes required for sporulation. This study indicates that yeast cells have distinct metabolic requirements at different phases of meiosis, which may reflect regulation that realizes the optimal outcome of sporulation. Our meiosis-specific network models provide a framework for an in-depth understanding of the roles of enzymes and reactions, and may open new avenues for engineering metabolic pathways to improve sporulation efficiency.
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2005-01-01 | MODEL1303140001 | BioModels
Project description:Transription profile of Saccharomyces cerevisiae SK1 cultures undergoing synchronous sporulation. We have measured mRNA levels in synchronized SK1 cells immediately upon transfer to the sporulation medium and every 30 minutes after that for 6 hours. mRNA extracted from these cultures were converted to cDNA and hybridized to microarrays and log2 ratios of hybridization signal of each time point was compared to that of time zero (immediately prior to transfer to the sporulation medium). Keywords: Time course
2008-01-16 | GSE8506 | GEO
Project description:Cells were grown to saturation in YPD (YEP + 2% glucose) for 24 hours, diluted into YPA (YEP + 2% potassium acetate) at OD600= 0.3 and grown over night at 30C. Cells were washed with sterilized water the next day and re-suspended in SPII medium (0.3% potassium acetate, pH = 7.0) at OD600= 1.9 to induce sporulation. Cells were sporulated at room temperature or 30C as indicated. Sporulation medium containing benomyl was always prepared freshly on the day of the experiment following the directions in {Shonn, 2000 #90}. Briefly, DMSO (dimethyl sulfoxide, Sigma-Aldrich) or benomyl [Methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate, Sigma-Aldrich; 30 mg/ml stock in DMSO] was dissolved in near-boiling SPII medium to avoid precipitation. The medium was then allowed to slowly cool to 30C or room temperature. At the time of drug treatment, cells were filtered and immediately re-suspended in the medium containing benomyl or DMSO. Keywords = benomyl sporulation saccharomyces microtubule spindle checkpoint Keywords: ordered
2004-10-18 | GSE1693 | GEO
Project description:We have used genome-wide expression profiling to investigate how budding yeast cells become committed to sporulation. Sporulating cells were transferred to growth medium at different stages of the process, and their transcription response was characterized. Most sporulation-induced genes were immediately down-regulated upon the transfer, even in committed cells that continued to sporulate. The metabolic-related transcription response of pre-committed cells or of mature spores transferred to growth medium was essentially the same as that of vegetative cells exposed to glucose. In contrast, committed cells elicited a unique, and dramatically different response. Our results suggest that cells ensure commitment to sporulation not by stabilizing the process, but by modulating their information processing in an active manner that may optimize sporulation in an environment-specific manner. Keywords: Time course
2006-01-25 | GSE3814 | GEO
Project description:We have used genome-wide expression profiling to investigate how budding yeast cells become committed to sporulation. Sporulating cells were transferred to growth medium at different stages of the process, and their transcription response was characterized. Most sporulation-induced genes were immediately down-regulated upon the transfer, even in committed cells that continued to sporulate. The metabolic-related transcription response of pre-committed cells or of mature spores transferred to growth medium was essentially the same as that of vegetative cells exposed to glucose. In contrast, committed cells elicited a unique, and dramatically different response. Our results suggest that cells ensure commitment to sporulation not by stabilizing the process, but by modulating their information processing in an active manner that may optimize sporulation in an environment-specific manner. Keywords: Time course
2006-01-25 | GSE3820 | GEO
Project description:We have used genome-wide expression profiling to investigate how budding yeast cells become committed to sporulation. Sporulating cells were transferred to growth medium at different stages of the process, and their transcription response was characterized. Most sporulation-induced genes were immediately down-regulated upon the transfer, even in committed cells that continued to sporulate. The metabolic-related transcription response of pre-committed cells or of mature spores transferred to growth medium was essentially the same as that of vegetative cells exposed to glucose. In contrast, committed cells elicited a unique, and dramatically different response. Our results suggest that cells ensure commitment to sporulation not by stabilizing the process, but by modulating their information processing in an active manner that may optimize sporulation in an environment-specific manner. Keywords: Time course
2006-01-25 | GSE3819 | GEO
Project description:We have used genome-wide expression profiling to investigate how budding yeast cells become committed to sporulation. Sporulating cells were transferred to growth medium at different stages of the process, and their transcription response was characterized. Most sporulation-induced genes were immediately down-regulated upon the transfer, even in committed cells that continued to sporulate. The metabolic-related transcription response of pre-committed cells or of mature spores transferred to growth medium was essentially the same as that of vegetative cells exposed to glucose. In contrast, committed cells elicited a unique, and dramatically different response. Our results suggest that cells ensure commitment to sporulation not by stabilizing the process, but by modulating their information processing in an active manner that may optimize sporulation in an environment-specific manner. Keywords: Time course
2006-01-25 | GSE3818 | GEO