Project description:Saccharomyces cerevisiae is unique among yeasts for its ability to grow rapidly in the complete absence of oxygen. S. cerevisiae is therefore an ideal eukaryotic model to study physiological adaptation to anaerobiosis. Recent transcriptome analyses have identified hundreds of genes that are transcriptionally regulated by oxygen availability but the relevance of this cellular response has not been systematically investigated at the key control level of the proteome. Therefore, the proteomic response of the S. cerevisiae to anaerobiosis was investigated using metabolic stable isotope labeling in aerobic and anaerobic glucose-limited chemostat cultures, followed by proteome analysis to relatively quantify protein expression. Using independent replicate cultures and stringent statistical filtering, a robust dataset of 474 quantified proteins was generated, of which 249 showed differential expression levels. While some of these changes were consistent with previous transcriptome studies, many responses of S. cerevisiae to oxygen availability were hitherto unreported. Comparison of transcriptome and proteome from identical cultivations yielded strong evidence for post-transcriptional regulation of key cellular processes, including glycolysis, amino-acyl tRNA synthesis, purine-nucleotide synthesis and amino-acid biosynthesis. The use of chemostat cultures provided well-controlled and reproducible culture conditions, which are essential for generating robust datasets at different cellular information levels. Integration of transcriptome and proteome data led to new insights in the physiology of anaerobically growing yeast that would not have been apparent from differential analyses at either the messenger RNA or protein level alone, thus illustrating the power of multi-level studies in yeast systems biology. Protein levels versus transcript level: Systematic analysis of the control levels at which the yeast response to anaerobiosis takes place was performed using previously published transcript data obtained from yeast cultures grown under strictly identical conditions as described for the current proteome analysis. Affymetrix microarrays from five aerobic and four anaerobic independent culture replicates were used for this analysis. These comparison data are summarized in the table below. These array data are publicly available at the gene expression repository Gene Expression Omnibus under accession number GSE4804. Keywords: proteomic, nanoflow-LC-MS/MS
Project description:mccc-1(ww4) mutant animals has no obvious developmental defect, but we observed different abundance of many metabolites by LC-MS/MS analysis. Then, we assumed different metabolite abundance is associated with different metabolic gene expression, sucha that RNA-seq was performed to examine differently expressed gene.
Project description:JS-K, a NO donor which capable to induce cancer apopotosis, it's killing mechanism was investigated in this study. We found out that JS-K induce apopotosis via deregulating the GSH/GSSG redox couple. Leukemia cells were treated with JS-K and then assayed for metabolic changes by LC/MS and gene expression alterations by microarray.
Project description:Identification of targets of the protein disulfide reductase thioredoxin using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and thiol specific differential labeling with isotope-coded affinity tags (ICAT). Reduction of specific target disulfides is quantified by measuring ratios of cysteine residues labeled with the heavy (13C) and light (12C) ICAT reagents in peptides derived from tryptic digests of Trx-treated and non-treated samples. Keywords: protein, LC-MS/MS, ICAT
Project description:Sudden cardiac death (SCD) associated with heart failure (HF) is a multifactorial problem requiring a systems level approach applied to suitable experimental animal models with features of the human disease. Here we examine key regulatory pathways underlying the transition from compensated hypertrophy (HYP) to decompensated HF and SCD by integrated analysis of the transcriptome, proteome and metabolome. In a guinea pig model of acquired long QT syndrome and HF/SCD, relative protein abundances from sham-operated, HYP and HF hearts were assessed using isobaric tags for relative and absolute quantification (iTRAQ), prior to liquid chromatography and tandem mass spectrometry (LC-MS/MS). Metabolites were quantified by LC-MS/MS or gas chromatography coupled to MS (GC-MS). Transcriptome profiles were obtained using DNA microarrays. The guinea pig HF proteome exhibited classic biosignatures of cardiac HYP, left ventricular dysfunction, fibrosis, cellular degeneration, inflammation and extravasation. Fatty acid metabolism, mitochondrial transcription/translation factors, antioxidant enzymes, and other mitochondrial processes, were downregulated in HF, but not HYP. Proteins upregulated in HF are consistent with extracellular matrix remodeling, cytoskeletal remodeling, and acute phase inflammation markers. Among metabolites, downregulation of acyl-carnitines was observed in HYP, while fatty acids accumulated in HF. Levels of the tricarboxylic acid (TCA) cycle metabolite, citrate, and the potent inhibitor, 2-methylcitrate, increased upon transition from HYP to HF. Correlation of the magnitude of transcript and protein changes in HF is weak (R2=0.23), indicating that targeting transcript/proteome may reveal inform post-transcriptional gene regulation in HF. Proteome/Metabolome integration suggests metabolic bottlenecks in fatty acyl-CoA processing by carnitine palmitoyl transferase (CPT1B) as well as TCA cycle inhibition. We present a model in which hallmarks of acute signaling in HF, including Ca2+ dysregulation and low cAMP levels, are coupled to mitochondrial metabolic and antioxidant defects, through a CREB/PGC1-alpha transcriptional axis.