Project description:The species Campylobacter jejuni is naturally competent for DNA uptake; nevertheless, nonnaturally transformable strains do exist. For a subset of strains we previously showed that a periplasmic DNase, encoded by dns, inhibits natural transformation in C. jejuni. In the present study, genetic factors coding for DNase activity in absence of dns were identified. DNA arrays indicated that nonnaturally transformable dns-negative strains contain putative DNA/RNA non-specific endonucleases encoded by CJE0566 and CJE1441 of strain RM1221. These genes are located on C. jejuni integrated element 2 and 4. Expression of CJE0566 and CJE1441 from strain RM1221 and a homologous gene from strain 07479 in DNase-negative Escherichia coli and C. jejuni strains indicated that these genes code for DNases. Genetic transfer of the genes to a naturally transformable C. jejuni strain resulted in a decreased efficiency of natural transformation. Modelling suggests that the C. jejuni DNases belong to the Serratia nuclease family. Overall, the data indicate that the acquisition of prophage encoded DNA/RNA non-specific endonucleases inhibits the natural transformability of C. jejuni through hydrolysis of DNA. The genomic diversity of 15 naturally competent or nonnaturally transformable Campylobacter jejuni strains were examined by microarray-based comparative genomic indexing (CGI) analysis. The CGI analysis allowed the assessment of CDS content for each C. jejuni strain relative to the C. jejuni DNA microarray, which comprises ORFs from strains NCTC 11168, RM1221. ORFs were spotted in duplicate. Genomic DNA from strains NCTC 11168/RM1221 were used as a reference DNA and competitively hybridized with genomic DNA from each of the other C. jejuni strains. Two replicates for each strain were performed. Data normalization was performed as in Parker et al. J Clin Microbiol 2006, 44(11):4125-4135.
Project description:The impact of dietary Chlorella vulgaris and carbohydrate-active enzymes (CAZymes) on the gut of weaned piglets was investigated using an integrated NMR-metabolomics and LC-MS/MS proteomics approach.
Project description:We classified samples and deciphered a key genes signature of intratumor heterogeneity by Principal Component Analysis and Weighted Gene Co-expression Network Analysis. At the genome level, we identified common GB copy number alterations and but a strong inter-individual molecular heterogeneity.
Project description:Here we examine key regulatory pathways underlying the transition from compensated hypertrophy (HYP) to decompensated heart failure (HF) and sudden cardiac death (SCD) in a guinea pig model by integrated multi-ome analysis. Relative protein abundances from sham-operated, HYP and HF hearts were assessed by iTRAQ shotgun LC-MS/MS. Metabolites were quantified by LC-MS/MS or GC-MS. Transcriptome profiles were obtained using DNA microarrays. The guinea pig HF proteome exhibited classic biosignatures of cardiac HYP, left ventricular dysfunction, fibrosis, 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 implicate 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. Correlation of transcript and protein changes in HF is weak (R2=0.23), suggesting transcript/proteome divergence may reveal 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 by which acute signaling in HF, including Ca2+ dysregulation and low cAMP levels, is coupled to mitochondrial metabolic and antioxidant defects, through a CREB/PGC1 transcriptional axis. Animal Model The guinea pig model of heart failure and sudden cardiac death has been described previously. Briefly, the HF and SCD guinea pig model was produced by combining ascending aortic constriction (AC) and daily isoproterenol challenge (ACi model). Specifically, Hartley guinea pigs (~250 g; Hilltop Lab Animals) were anesthetized with 4% isoflurane in a closed box for 4min, and then intubated and ventilated with oxygen and 2% isoflurane. Ascending aortic constriction (AC) was produced by tying a suture around the ascending aorta using an 18‐gauge needle as a spacer, which was then removed. For sham operations the procedure was identical though the suture was not tied. After the procedure, bupronex (0.05 mg/kg) was administered via intramuscular injection for analgesia and animals were observed until full recovery. Isoproterenol was administered daily by intra peritoneal injection at 1 mg/kg for the first week after surgery and at 2 mg/kg for a subsequent 3 weeks. As characterized previously (1), cardiac function of ACi animal is well compensated in the first 2 weeks (HYP) but declined rapidly thereafter (HF). Hypertrophic heart was collected between 1-2 weeks post-surgery (ACi-2w), whereas failing heart was collected at 4 weeks after surgery (ACi-4w). Following retrograde perfusion with 20ml Tyrode’s solution, excised hearts were Snap-frozen in liquid N2 and stored at -80°C Experimental Design The experiment consisted of 3 treatment groups: 1) HYP (ACi-2wk), 2) HF (ACi-4wk) 3) sham-operated animals with daily administration for 4 weeks (Shami-4w). 1 heart from each group was included in an iTRAQ 4-plex experiment wherein peptides from each heart are subjected to reaction with an isobaric label. The experiment was repeated twice, yielding a total of 3 independent experiments quantifying the peptides from 9 hearts. ITRAQ reagents were shuffled among treatment groups for each experiment to minimize labeling bias.
Project description:To identify substrates of the ubiquitinating E3 enzyme Rsp5 we applied purified Rsp5 to duplicate protein arrays. The Rsp proteins were expressed as fusion proteins to GST. We used as a control Ubr1, a RING domain containing E3 ligase We analyzed Rsp5 from S.cerevisiae on duplicate arrays, with four control chips, two without Rsp5 and two with Ubr1.
Project description:To profile the expression of circulating miRNAs in a mouse model of diet-induced obesity (DIO) with subsequent weight-reduction with low-fat diet (LFD), eighteen C57BL/6 male mice were grouped into three subgroups as: (1) Control: the mice fed with the standard AIN-76A (fat: 11.5 kcal%) diet for 12 wks; (2) DIO: the mice fed with 58 kcal% high-fat diet for 12 wks; (3) DIO+LFD: the mice fed with high-fat diet for 8 wks to induce obesity, then changed to 10.5 kcal% low-fat diet for subsequent 4 wks. C57BL/6 mice were purchased from BioLasco (Taipei, Taiwan). All housing conditions were maintained, and surgical procedures, including analgesia, were performed in an Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC)-accredited SPF facility according to national and institutional guidelines. In this experiment, eighteen C57BL/6 wild type male mice were randomly grouped into three subgroups (n=6 in each group): (1) Control: the control mice were fed ad libitum a standard AIN-76A (fat: 11.5 kcal%) diet for 12 wks; (2) DIO: the mice were fed ad libitum a 58 kcal% HFD (D12331; Research Diets Inc., New Brunswick, NJ) for 12 wks to induce obesity; (3) DIO+LFD: the mice fed ad libitum a 58 kcal% HFD (D12331) for 8 wks to induce obesity, then continued the feeding of 10.5 kcal% LFD (D 12329; Research Diets Inc.) for additional 4 wks. Weight measurements were performed on a weekly basis to for these three groups of mice. Evaluation of blood glucose levels was performed at the beginning and in the end of the experiment to confirm that the HFD-fed mice developed an obese and insulin resistant phenotype. After the end of experiment at 12w, all mice were killed. The abdominal WAT of each mice was removed and weighted. Paraffin-embedded abdominal WAT was sectioned at 5 M-NM-<m and stained with hematoxylin and eosin to measure mean adipocyte area. A volume of 1 mL of whole blood was collected into a plain tube and allowed to clot for 1 hour. The sera samples were aliquoted after centrifugation at 3,000 M-CM-^W g for 10 minutes and stored at M-bM-^HM-^R80M-BM-0C until further analysis.
Project description:The aim was to examine changes in gene expression of the endometrium exposed to long-term tamoxifen treatment in comparison to age matched controls. To achieve this, endometrial tissues were obtained from women receiving tamoxifen treatment who were undergoing a hysterectomy. Using cDNA microarrays, gene expression changes in the postmenopausal endometrium of these women was compared with that in endometrium of age matched women not receiving tamoxifen. Endometrial tissue from post-menopausal women was obtained following ethical approval from the Leicester NHS Trust. None of the women had received any hormonal treatment for two months prior to the procurement of the specimens. Tissues were taken from untreated women (n=6) or those treated for 4 to 5 years with tamoxifen (20mg/day) (n=4), aged 58-82 (65 ± 9.1, mean ± SD). Total RNA was extracted. Controls were pooled. RNA labelling, hybridisation and analysis of fluorescence was carried out as described by Turton et al (2001). Cy3/Cy5 Dye swap labelling was carried out on samples from each patient. Reference: Turton NJ et. al. (Oncogene (2001) 20, 1300-1306
Project description:Background: The cellular reservoir of latent HIV infection remains the main barrier to cure this virus. Elimination of this reservoir would be possible, if molecular identity of latently infected cells were fully elucidated. Biomarkers proposed previously were able to capture only a relatively small fraction of all reservoir cells. In the present study, we set out to conduct comprehensive molecular profiling, at the protein and RNA levels, of CD4+ T cells latently infected with HIV in vitro, using liquid chromatography-mass spectrometry (LC-MS) and RNA sequencing (RNA-Seq), respectively. Protein-based methods such as quantitative proteomic profiling using LC-MS may be more beneficial due to direct transferability of results to antibody-based approaches to capture latently infected cells. Integrated analysis of proteomic and transcriptomic data adds a level of validation and increases confidence in identified biomarkers. Flow cytometry and integrated HIV DNA assay were further used to enrich for latently infected cells with antibodies against selected biomarker proteins. Results: Using quantitative proteomics, we identified a total of 10,886 proteins (peptide level FDR < 0.05), of which 673 were up- and 780 down-regulated in latently infected compared to mock-infected cells in vitro (p < 0.05). Among these proteins, 21 were dysregulated at the RNA level in the same direction. Pathway analysis identified p53, mTOR, Wnt and NOTCH signaling, demonstrating that our in vitro model reflects known mechanisms of latency establishment and maintenance. Comparison of identified proteins with other proteomics studies revealed that identified molecular signatures of latency depend on technology and cell types used; however, a subset of proteins were identified both in the present, and at least one other study. Antibodies against selected protein markers, CEACAM1 and PLXNB2, could enrich for latently infected cells from mixed cell population 3-10 fold (5.8 fold average, p < 0.001). Conclusion: Two new molecules, CEACAM1 and PLXNB2, were identified as biomarkers for HIV latency. However, the level of enrichment for latently infected cells compared to biomarkers proposed previously was not improved. These results are consistent with the idea that each proposed biomarker defines only a subset of latently infected cells, and that a combined biomarker will be required to capture or target the latent HIV reservoir represented by different cell types.
Project description:We report an integrated analysis incorporating DNA copy number analyses, somatic exon mutations, mRNA expression via RNA-sequencing, and shotgun mass spectrometry analysis of protein abundance in 108 surgically resected squamous cell lung cancers (SCC) with accompanying clinical outcome, evaluation of tumor pathology, and other clinically relevant data. We identified three major subtypes of SCC at the proteomic level, with two groups associated with inflammation/immune response or oxidation-reduction biology. Inflamed tumors could be further sub-classified based on neutrophil infiltration or antigen presentation proteomes and reflected patterns of infiltrating immune cells. No gene mutations, mRNA signatures, or proteomic subclasses were associated with outcomes; however, the presence of B-cell rich tertiary lymph node structures could be associated with better patient outcomes. By integrating our proteogenomic data with publicly available RNA interference screen data, we identified TP63, PSAT1, and AKR1C3 as vulnerabilities in SCC, particularly in the redox proteomic group. This cohort and its deep molecular data serves as an important resource to better understand biology and targets associated with SCC.