Project description:Drosophila Orb, the homologue of vertebrate CPEB is a key translational regulator involved in oocyte polarity and maturation through poly(A) tail elongation of specific mRNAs. orb has also an essential function during early oogenesis which has not been addressed at the molecular level. Here, we show that orb prevents cell death during early oogenesis, thus allowing oogenesis to progress. It does so through the repression of autophagy, by directly repressing, together with the CCR4 deadenylase, the translation of Autophagy-specific gene 12 (Atg12) mRNA. Autophagy and cell death observed in orb mutant ovaries are reduced by decreasing Atg12 or other Atg mRNA levels. These results reveal a role of Orb in translational repression and identify autophagy as an essential pathway regulated by Orb during early oogenesis. Importantly, they also establish translational regulation as a major mode of control of autophagy, a key process in cell homeostasis in response to environmental cues. Orb RIP-chip vs mock IP on ovaries from mature 3-5 day old females.
Project description:Drosophila Orb, the homologue of vertebrate CPEB is a key translational regulator involved in oocyte polarity and maturation through poly(A) tail elongation of specific mRNAs. orb has also an essential function during early oogenesis which has not been addressed at the molecular level. Here, we show that orb prevents cell death during early oogenesis, thus allowing oogenesis to progress. It does so through the repression of autophagy, by directly repressing, together with the CCR4 deadenylase, the translation of Autophagy-specific gene 12 (Atg12) mRNA. Autophagy and cell death observed in orb mutant ovaries are reduced by decreasing Atg12 or other Atg mRNA levels. These results reveal a role of Orb in translational repression and identify autophagy as an essential pathway regulated by Orb during early oogenesis. Importantly, they also establish translational regulation as a major mode of control of autophagy, a key process in cell homeostasis in response to environmental cues. Orb RIP-chip vs mock IP on ovaries from newly eclosed females.
Project description:The experimental data indicate that during a persistent infection, lymphocytic choriomeningitis virus (LCMV) may both directly or indirectly modulate the regulatory cellular processes and alter the cellular functions that are not critical for the survival, but are needed for the homeostasis in the organism. Two-dimensional differential in-gel electrophoresis (2D-DIGE) and MALDI-TOF MS/MS analyses were used to determine the cellular proteome response of HeLa cell line to persistent LCMV infection. Quantitative analysis revealed 24 differentially abundant proteins, half of which were up-regulated and the rest down-regulated. Functional categorization showed that LCMV-responsive proteins were mainly involved in metabolism, stress and defense responses. Among identified proteins, significant changes were found for peroxiredoxins, family of antioxidant enzymes. Decreased amount of these antioxidant proteins was accompanied with the elevation of ROS content in infected cells.
Project description:This study considers the physiological modulation of liver proteins due to the supplementation with fish oils under two different dietary backgrounds: low- or high- fat and sucrose diets, and the effect of their combination with an antioxidant agent (grape polyphenols) which provides reducing power. For this scope, a quantitative proteomics approach based on the Isobaric Tag for relative and Absolute Quantitation methodology (iTRAQ)-coupled to nano-LC-MS/MS and complemented with 2D-DIGE analysis were used for determining the regulation of liver proteins exerted by the supplementation with fish oils, polyphenols or their combination of Wistar Kyoto rats in the two chosen dietary backgrounds. This experimental design was useful to investigate if the behavior of fish oils changes when the dietary background is modified and the possible synergy between fish oils and polyphenols. Results show that the capacity of fish oils, polyphenols or their combination for down or up-regulating liver proteins depends on the dietary context. In the background of low-fat low-sucrose healthy diets, 10 different proteins were altered by the sum of three supplements, in opposite to the 45 altered proteins found in the high-fat high-sucrose unhealthy diets. In both situations, fish oils seemed to be the main force for regulating liver proteins, although the addition of polyphenols was able to modulate some fish oils effects. Moreover, we provide evidence of the effect of fish oils and their combination with grape polyphenols for improving biochemical parameters and for reducing enzymes of hepatic lipogenesis and glycolysis, for enhancing fatty acid beta oxidation and insulin signaling and for the amelioration of endoplasmic reticule stress and protein oxidation when are included in an unhealthy diet.
Project description:E4F1 is a ubiquitously expressed zinc-finger protein of the Gli-Kruppel family that was first identified, more than 30 years ago, as a cellular target of the adenoviral oncoprotein E1A13S (Ad type V), required for transcriptional regulation of adenoviral genes. In order to identify the p53-independent program controlled by E4F1, we performed microarray analyses in p53 KO and p53 KO; Ha-RasV12-transformed mouse embryonic fibroblasts (MEFs) in wild type and E4F1-inactivated cells. To address p53-independent E4F1 transcriptome, a 12 chip array study has been realized using total RNA recovered from wild-type (E4F1+/flox, CRE infected; odd Samples) MEFs and E4F1-depleted (E4F1-/flox, CRE infected; even Samples) MEFs in p53-/- (Samples 1 to 12) and p53-/-, Ha-RasV12 background (Samples 13 to 24). p53-/- MEFs were derived from 13.5-day mouse embryos. Transformed p53-/- MEFs were generated by infection with a recombinant retrovirus encoding for Ha-RasV12. Three independent biological replicates of wild-type and knock-out MEFs for E4F1 have been used on the two genetic backgrounds.
Project description:Objective of the study is to find out the differentially regulated genes of Mycobacterium BCG strain in extended stationary phase comparison to log phase growth and resuscitation phase. Mycobacterium BCG culture was grown in Sauton medium at 37o C without shaking. Cells at A600 0.6-0.8 were harvested as log phase culture. The cells harvested after 5 months incubation at 37oC without shaking became non culturable and were harvested as extended stationary phase cells. The extended stationary phase cells were treated with resuscitation promoting factor (Rpf) from Micrococcus luteus and harvested after 8 days. Cells of this stage were treated as resuscitation phase cells. Gene expression profiling was carried out using Agilent microarray platform. Keywords: Extended stationary phase, Log phase growth and Resuscitation phase. ⢠Organism: Mycobacterium tuberculosis BCG ⢠Slides: Agilentâs Mycobacterium tuberculosis custom array 4x44k (G2514F) AMADID No: 016013 ⢠Labeling kit: Ambion Message Amp II Bacteria a RNA Amplification Kit Cat# 1790 ⢠Labeling Method: T7 promoter based-linear amplification to generate labeled complementary RNA ⢠Total RNA and cRNA Purification Kit: Qiagenâs RNeasy minikit Cat#74104 ⢠Hybridization Kit: Agilentâs In situ Hybridzation kit 5184-3568 ⢠RNA quality was checked using Bioanalyzer. Hybridization protocol 825ng each of labeled control cRNA was mixed with 825ng of treated labelled cRNA, mixed with appropriate amount of blocking buffer and hybridization buffer (Agilent Technologies). The hybridization mix was applied on to the backings and hybridized to custom designed 60mer Mycobacterium tuberculosis microarray using sure hyb chambers at 65degC for 17 hours. Slides were washed with gene expression wash buffer 1 and 2 (Agilent Technologies) followed by Acetonitrile. Scan protocol Laser detection of Cyanine 3 and Cyanine 5 fluorescence is performed using a confocal scanning instrument containing two tuned lasers, which excite Cyanine dyes at the appropriate wavelengths. Description Slides were scanned at 5 micron resolution using Agilent scanner.Automated feature extraction was done using Agilentâs Feature Extraction Software. Data processing Analysis of feature extracted data was done using Agilentâs GeneSpring GX V 7.3.1 software. Pre-processing of the replicate experiment data was done to flag the outliers. Normalization of the data was done using per spot per chip intensity dependant lowess normalization and dye swap experiment was data transformed. Genes with log2 ratio of 1.29 and above in replicate experiments were considered as up regulated and 0.81 and below was considered down regulated. p-value was calculated by GeneSpring GX for each gene on the basis of replicate probes to indicate statistical significance. Biological significance of differentials were analyzed using Genotypics Biointerpreter - Web based tool for biological interpretation of given genelist.
Project description:We previously showed that doxycycline and carprofen , a veterinary non-steroidal anti-inflammatory drug, have synergistic antimicrobial activity against methicillin-resistant Staphylococus pseudintermedius (MRSP) carrying the tetracycline resistance determinant TetK. To elucidate the molecular mechanism of this synergy, we investigated the effects of the two drugs, individually and in combination, using a comprehensive approach including two-dimensional differential in-gel electrophoresis (2D DIGE).
Project description:Developmental gene expression results from the orchestrated interplay between genetic and epigenetic mechanisms. Here, we describe upSET, a transcriptional regulator encoding a SET domaincontaining protein recruited to active and inducible genes in Drosophila. However, unlike other Drosophila SET proteins associated with gene transcription, UpSET is part of an Rpd3/Sin3-containing complex that restricts chromatin accessibility and histone acetylation to promoter regions. In the absence of UpSET, active chromatin marks and chromatin accessibility increase and spread to genic and flanking regions due to destabilization of the histone deacetylase complex. Consistent with this, transcriptional noise increases, as manifest by activation of repetitive elements and off-target genes. Interestingly, upSET mutant flies are female sterile due to upregulation of key components of Notch signaling during oogenesis. Thus UpSET defines a class of metazoan transcriptional regulators required to fine tune transcription by preventing the spread of active chromatin. For determining DamID based UpSET chromatin profile, three biological replicates were used. For evaluating chromatin accessibility, two biological replicates were performed.
Project description:To gain insight into the molecular mechanisms at work during progression through the pre-erythrocytic stages, a comparative microarray based transcriptional study was under taken on radiation attenuated (RAS) and wild type sporozoites (wtSPZ) as well as, and liver stage parasites collected 24 hours (24hrLS) and 48 hours (48hrLS) after wild type sporozoite infection. We were able to identify ~1100 genes significantly differentially expressed during one or more of the pre-erythrocytic stages relative to the mixed blood stages. This study compared the gene expression profiles of radiation attenuated sporozoites (RAS), wild type sporooites (wtSPZ), and infected hepatocytes collected 24hr (24hrLS) and 48hr (48hrLS) after sporozoite infection, using a common reference design. Each sample was hybridized with an equal amount of reference RNA. 48hrLS: 4 biological replicates, with 2 total technical replicates and one dye swap; 24hrLS: 4 biologicla replicates, with 3 total technical replicates; RAS: 2 biological replicates, with 2 technical replicates total, and two tota dye swaps; wtSPZ: 2 biological replicates, with 2 total technical replicates and 2 total dye swaps
Project description:Objective of the study is to find out the differentially regulated genes in Mycobacterium bovis BCG subjected to hypoxic condition. Gene expression profiling was carried out using Agilent microarray platform. Keywords: Hypoxia response Mycobacterium cells were lysed by bead beating in AL Buffer of Qiagenâs bacterial RNA kit. RNA was purified as per manufacturerâs instructions. RNA quality control was done using Agilent 2100 Bioanalyzer lab on a chip. Total RNA (500ng) of Mycobacterium under hypoxia and log phase were labelled with Cy3 and Cy5 (Perkin Elmer) dyes respectively using Ambion Message AmpII bacteria kit as per manufacturer recommended protocol. To eliminate dye bias, technical replicates were labelled in the reverse direction i.e log phase culture with Cy5 and hypoxia with Cy3. 825ng each of labeled control cRNA was mixed with 825ng of treated labelled cRNA, mixed with appropriate amount of blocking buffer and hybridization buffer (Agilent Technologies). The hybridization mix was applied on to the backings and hybridized to custom designed 60mer M.tuberculosis H37Rv microarray using sure hyb chambers at 65degC for 17 hours. Slides were washed with gene expression wash buffer 1 and 2 (Agilent Technologies) followed by Acetonitrile and scanned at 5 micron resolution using Agilent scanner. Automated feature extraction was done using Agilentâs Feature Extraction Software. Statistical analysis of microarray data was done using GeneSpring GX and Biological analysis of the differentially regulated genes were done using Genotypics Biointerpreter -Web based tool for biological interpretation of gene list in a click of mouse.