Project description:Aneuploidy is a condition frequently found in tumor cells but how it affects cellular physiology is not known. We have characterized one aspect of aneuploidy, the gain of extra chromosomes. We created a collection of haploid yeast strains that each bear an extra copy of one or more of almost all of the yeast chromosomes. Their characterization revealed that aneuploid strains share a number of phenotypes, including defects in cell cycle progression, increased glucose uptake and increased sensitivity to conditions interfering with protein synthesis and protein folding. These phenotypes were observed only in strains carrying additional yeast genes indicating that they reflect the consequences of additional transcription and translation as well as the resulting imbalances in cellular protein composition. We conclude that aneuploidy causes not only a proliferative disadvantage but also a set of phenotypes that is independent of the identity of the individual extra chromosomes. Keywords: CGH, gene expression This series of microarrays compares yeast strains carrying extra chromosomes to wt yeast with normal chromosome content. Both DNA/CGH and gene expression comparisons were done, as noted. In some experiments, biological replicates were performed as noted. Reference wt nucleic acid was most commonly labeled with Cy3. Experiments labeled as "swap" have the wt reference nucleic acid labeled with Cy5, and ratio values for these experiments are reported as Cy3/Cy5.
Project description:We constructed a database containing 248,000 exon sequences from 23,000 human RefSeq genes and compared each human exon with its best matching sequence in the January 2005 version of the rhesus genome project list of 486,000 DNA contigs. Best matching rhesus exon sequences for each of the 23,000 human genes were then concatenated in the proper order and orientation to produce a rhesus virtual transcriptome. Microarray probes were designed, one per gene, to the region closest to the 3? untranslated region (UTR) of each rhesus virtual transcript. Each probe was compared to a composite rhesus/human transcript database to test for cross-hybridization potential yielding a final probe set representing 18,296 rhesus/human gene orthologs, including transcript variants, and over 17,000 distinct genes. We hybridized mRNA from rhesus brain and spleen to both the EST- and genome-derived microarrays. Besides four-fold greater gene coverage, the genome-derived array also showed greater mean signal intensities for genes present on both arrays. Genome-derived probes showed 99.4% identity when compared to 4,767 rhesus GenBank sequence tag site (STS) sequences indicating that early stage low-pass versions of complex genomes are of sufficient quality to yield valuable functional genomic information when combined with finished genome information from a closely related species.
Project description:There is a growing need for novel antiviral therapies that are broad-spectrum, effective, and not subject to resistance due to viral mutations. Using high-throughput screening methods, including computational docking studies and an ISG54-luciferase reporter assay, we identified a class of isoflavone compounds that act as specific agonists of innate immune signaling pathways and cause activation of the IRF-3 transcription factor. The objective of the microarray study was to examine the biological pathways associated with global gene expression changes following agonist treatment. Total RNA isolation and mRNA amplification were performed on equal masses of total RNA from MRC5 cells treated with either DMSO (negative control; n=3), or 10μM of the isoflavone agonist KIN 101 (n=3) at 20 hours post treatment. As a positive control for response to an RNA virus, total RNA isolation and mRNA amplification was performed on equal masses of total RNA from MRC5 cells infected with Sendai virus (n=3) at 20 hours post infection.
Project description:These experiments were done to compare the transcriptional response to high temperature of disomic yeast to that of WT yeast. Total RNA from strains and timepoints specified was labeled by Cy3- this was compared to WT total RNA in all cases.
Project description:15-Lipoxygenase 2 (15-LOX2), a human-specific lipid-peroxidizing enzyme, is mainly expressed in luminal compartment of the normal prostate and often decreased or lost in prostate cancer (PCa). Previous studies from our lab implicate 15-LOX2 as a functional tumor suppressor. To better understand the biological role of 15-LOX2 in vivo, we established prostate-specific 15-LOX2 transgenic mice using the ARR2PB promoter. Unexpectedly, 15-LOX2 expression resulted in age-dependent prostatic hyperplasia. Interestingly, transgenic expression of 15-LOX2sv-b, a splice variant that lacks the arachidonic acid metabolizing activity, also induced hyperplasia and enlargement of the prostate. Prostatic hyperplasia induced by both 15-LOX2 and 15-LOX2sv-b was associated with an increase in proliferative (i..e., Ki67+) and luminal cells but 15-LOX2-induced hyperplasia was also accompanied by a prominent increase in basal cells. Microarray analysis revealed distinct gene expression profiles that could help explain the prostate phenotypes. Strikingly, 15-LOX2 (but not 15-LOX2sv-b) transgenic prostate showed up-regulation of several well-known stem/progenitor cell molecules including Sca-1, Trop2, p63 and Psca. Prostatic hyperplasia caused by both 15-LOX2 and 15-LOX2sv-b did not progress to PCa over >5 years of observations. Mechanistically, hyperplastic prostate lobes (especially those of the 15-LOX2 mice) showed a dramatic increase in senescent cells revealed by increased SA-ßgal, HP1, and p27Kip1 staining. Collectively, our results suggest that 15-LOX2 expression in mouse prostate leads to hyperplasia that activates the senescence checkpoint, which may in turn function as a barrier to tumor development. RNA was isolated from combined prostatic lobes of 6 mice (to reduce inter-animal variation) from ~2.5 month old (young; y) 15-LOX2 (line fl26), 15-LOX2sv-b (line svb9), wild type (wt) and ~15 month old (old; o) wt mice and hybridized onto Agilent's whole mouse genome oligoarrays arrays (G4122A) in fl26y(vs)wty, svb9y(vs)wty and wto(vs)wty combinations. The hybridizations were carried out in duplicates using an independent set of samples (biological replicates).
Project description:Stalk-eyed flies (family Diopsidae) are a model system for studying sexual selection due to the elongated and sexually dimorphic eye-stalks found in some species. These flies are of additional interest because their X chromosome is derived largely from an autosomal arm in other flies. To investigate how sex-biased expression arose on the novel X we compared gene expression between males and females using oligonucleotide microarrays and RNA from developing eyestalk tissue in the sexually monomorphic diopsid, Teleopsis quinqueguttata. We use probe sequence divergence to evaluate cross-species ascertainment bias and chromosome assignment to determine if sex linkage influence expression. Microarray analysis revealed sex-biased expression for only 1.9% of 3,748 genes expressed in eye-antennal imaginal discs. Analysis of probe sequences between species indicates that the lack of sex-biased expression is not due to ascertainment bias. These findings indicate that the the majority of sex-biased gene expression observed in developing heads of the dimorphic species, T. dalmanni, is causally related to development of dimorphic head shape. Two-condition experiment, female vs. male RNA using larval eye discs and adult heads for one species (Teleopsis quinqueguttata)
Project description:Expression of mRNAs in an EBV-positive B-cell strain, 28-2. 28-2 are infected with a derivative of the B-958 strain of EBV, which expresses eGFP constitutively and LMP1 fused to mRFP from its native promoter. Single cells were sorted by flow cytometry for their levels of LMP1-mRFP (5% expressing the lowest levels of LMP1-mRFP or 5% expressing the highest levels of LMP1-mRFP) Two-condition experiment: Low v. High LMP1-mRFP expression. Biological replicates: 3 Low LMP1-mRFP, 3 High LMP1-mRFP. Samples were normalized to the expression of mRNAs in a pool of unsorted 28-2 cells.
Project description:Neuroendocrine prostate cancer (NEPC) is proliferative, invasive, and untreatable. Its molecular pathogenesis remains poorly understood but appears to require TP53 and RB1 aberration. In this study we modeled the development of NEPC from conventional prostatic adenocarcinoma using a unique patient-derived xenograft and identified up-regulation of the placental gene PEG10. We found that the androgen receptor and the E2F/RB pathway dynamically regulate distinct post-transcriptional and post-translational isoforms of PEG10 at different stages of NEPC development. In vitro, PEG10 promoted cell cycle progression from G0/G1 in the context of TP53 loss, and regulated Snail expression via TGF-β signaling to promote invasion. Finally we show in vivo proof of principal using antisense oligonucleotide that PEG10 is a novel therapeutic target for NEPC. Six patient-derived xenograft tumors from the LTL331 xenograft lineage (PMID: 24356420; http://www.livingtumorcentre.com/) after differing lengths of time post-host castration. No replicates.
Project description:aCGH experiment on cell-free DNA collected from the plasma of patients with castration-resistant prostate cancer. No replicates. castration-resistant prostate cancer vs male reference DNA
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.