Gene expression profile of squamous lung cancer cells are used to identify genes that are differentially regulated.
Interactome-transcriptome analysis reveals the high centrality of genes differentially expressed in lung cancer tissues.
No sample metadata fields
View SamplesCells constantly adapt to changes in their environment. In the majority of cases, the environment shifts between conditions that were previously encountered during the course of evolution, thus enabling evolutionary-programmed responses. In rare cases, however, cells may encounter a new environment to which a novel response is required. To characterize the first steps in adaptation to a novel condition, we studied budding yeast growth on xylulose, a sugar that is very rarely found in the wild. We previously reported that growth on xylulose induces the expression of amino-acid biosynthesis genes, in multiple natural yeast isolates. This induction occurs despite the presence of amino acids in the growth medium and is a unique response to xylulose, not triggered by any of the naturally available carbon sources tested. Propagating these strains for ~300 generations on xylulose significantly improved their growth rate. Notably, the most significant change in gene expression was the loss of amino acid biosynthesis gene induction. Furthermore, the reduction in amino-acid biosynthesis gene expression on xylulose was strongly correlated with the improvement in growth rate, suggesting that internal depletion of amino-acids presented the major bottleneck limiting growth in xylulose. We discuss the possible implications of our results for explaining how cells maintain the balance between supply and demand of amino acids during growth in evolutionary 'familiar' vs. 'novel' conditions. Overall design: mRNA profiles of 12 wt S. cerevisiae strains grown on either YPD or YP-xylulose, before and after 300 generations evolution on YP-xylulose
Rapid evolutionary adaptation to growth on an 'unfamiliar' carbon source.
Cell line, Subject
View SamplesWe show that aneuploidy is common in wild isolates of yeast, which are inherently tolerant to chromosome amplification and down-regulate expression at 40% of amplified genes. To dissect the mechanism of this dosage response, we generated isogenic strain panels in which diploid cells carried either two, three, or four copies of the affected chromosomes. Using a mixture of linear regression (MLR) model to classify genes, we find that expression is actively down regulated in proportion to increased gene copy at up to 30% of genes. Genes subject to dosage control are under higher expression constraint – but show elevated rates of gene amplification – in wild populations, suggesting that dosage compensation buffers copy number variation (CNV) at toxic genes Overall design: RNA-seq and transcriptome analysis of S. cerevisiae natural isolates having aneuploidy. Technical triplicate was performed for isogenic diploid strains having 2, 3 and 4 copies of a given chromosome (strain panels), while technical duplicate or singulate was performed on all other aneuploids.
Dosage compensation can buffer copy-number variation in wild yeast.
Subject
View SamplesWe carried out a global survey of age-related changes in mRNA levels in the C57BL/6NIA mouse hippocampus and found a difference in the hippocampal gene expression profile between 2-month-old young mice and 15-month-old middle-aged mice correlated with an age-related cognitive deficit in hippocampal-based explicit memory formation. Middle-aged mice displayed a mild but specific deficit in spatial memory in the Morris water maze.
Altered hippocampal transcript profile accompanies an age-related spatial memory deficit in mice.
Sex, Age, Specimen part
View SamplesThe ERK family of MAP kinase plays a critical role in growth factor-stimulated cell cycle progression from G0/G1 to S phase. But, how sustained activation of ERK promotes G1 progression has remained unclear. Here, our systematic analysis on the temporal program of ERK-dependent gene expression shows that sustained activation of ERK is required for induction and maintenance of the decreased expression levels of a set of genes. Moreover, our cell biological analysis reveals that these ERK-dependent downregulated genes have the ability to block S phase entry. Cessation of ERK activation at mid or late G1 leads to a rapid increase of these anti-proliferative genes and results in the inhibition of S phase entry. These findings uncover an important mechanism by which the duration of ERK activation regulates cell cycle progression through dynamic changes in gene expression, and identify novel ERK target genes crucial for the regulation of cell cycle progression.
Continuous ERK activation downregulates antiproliferative genes throughout G1 phase to allow cell-cycle progression.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Ars2 promotes proper replication-dependent histone mRNA 3' end formation.
Specimen part, Cell line, Treatment
View SamplesArs2 is a component of the nuclear cap-binding complex that is required for cellular proliferation and contributes to microRNA biogenesis. Arrays were performed to determine the repertoire of genes that change following knock-down of Ars2. Knock-down of DGCR8 was also performed to determine which changes in Ars2 knock-down cells resulted from defects in microRNA expression.
Ars2 promotes proper replication-dependent histone mRNA 3' end formation.
Specimen part, Cell line, Treatment
View SamplesWe found that CFIm68, a mRNA cleavage and polyadenylation factor implicated for alternative polyadenylation site choice, was co-purified with Thoc5, a component of human THO/TREX. Microarray analysis using human HeLa cells reveals knockdown of Thoc5 affects the expression of a subset of non-heat shock genes. Notably, depletion of Thoc5 attenuated the expression of the mRNAs polyadenylated at distal, but not proximal, polyadenylation sites, which phenocopied the depletion of CFIm68.
Human TREX component Thoc5 affects alternative polyadenylation site choice by recruiting mammalian cleavage factor I.
Cell line, Treatment
View SamplesPseudomonas aeruginosa undergoes cell elongation and forms robust biofilms during anaerobic respiratory growth using nitrate (NO3-) as an alternative electron acceptor. Understanding the mechanism of cell shape change induced upon anaerobiosis is crucial to the development of effective treatments against P. aeruginosa biofilm infection. Anaerobic growth of PAO1 reached higher cell density in the presence of vitamin B12, an essential coenzyme of class II ribonucleotide reductase. In addition, cell morphology returned to a normal rod shape. These results suggest that vitamin B12, the production of which was suppressed during anaerobic growth, can restore cellular machineries for DNA replication and therefore facilitate better anaerobic growth of P. aeruginosa with normal cell division.
Vitamin B12-mediated restoration of defective anaerobic growth leads to reduced biofilm formation in Pseudomonas aeruginosa.
No sample metadata fields
View SamplesBackground and Aims: Recent identification of intracellular DNA sensing pathways and involvement in numerous diverse disease processes including viral pathogenesis and autoimmunity suggests a role for these processes in liver pathology. The presence of these pathways in the liver and their role in HBV infection is unknown. Methods: In order to characterize the role of DNA sensing pathways in the liver, we utilized in vitro models. Microarray was performed on DNA treated and HBV infected hepatoma primary human hepatocytes. Results: Here we show that HBV infection and foreign DNA results in a significant innate immune response characterized by the production of inflammatory chemokines.
Hepatitis B Virus and DNA Stimulation Trigger a Rapid Innate Immune Response through NF-κB.
Specimen part, Treatment
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