We have used a combination of three high-throughput RNA capture and sequencing methods to refine and augment the transcriptome map of a well studied genetic model, Caenorhabditis elegans. The three methods include a standard (non-directional) library preparation protocol relying on cDNA priming and foldback that has been used in several previous studies for transcriptome characterization in this species, and two directional protocols, one involving direct capture of single stranded RNA fragments and one involving circular-template PCR (circligase). We find that each RNA-seq approach shows specific limitations and biases, with the application of multiple methods providing a more complete map than was obtained from any single method. Of particular note in the analysis were substantial advantages of circligase-based and ssRNA-based capture for defining sequences and structures of the precise 5'' ends (which were lost using the double strand cDNA capture method). Of the three methods, ssRNA capture was most effective in defining sequences to the polyA junction. Using datasets from a spectrum of C. elegans strains and stages and the UCSC Genome Browser, we provide a series of tools, which facilitate rapid visualization and assignment of gene structures. Overall design: single-strand-capture, double-strand-capture, and circligase-based RNA-seq
Co-option of the piRNA pathway for germline-specific alternative splicing of C. elegans TOR.
Sex, Specimen part, Cell line, SubjectView Samples
Transcriptome analysis of a population of control animals vs cisplatin-treated, in duplicate Overall design: A mixed population of worms representing all stages and growing under control conditions was exposed to 60 µg/ml of cisplatin for 24 hours at 20ºC. Treated and control samples weer collected in biological replicates.
Genetic and cellular sensitivity of <i>Caenorhabditis elegans</i> to the chemotherapeutic agent cisplatin.
Cell line, Treatment, SubjectView Samples
The transcriptomes of model organisms have been defined under specific laboratory growth conditions. The standard protocol for Caenorhabditis elegans growth and maintenance is 20ºC on an Escherichia coli diet. Temperatures ranging from 15ºC to 25ºC or feeding with other species of bacteria are considered physiological lab conditions, but the effect of these conditions on the worm transcriptome have not been well characterized. Here, we compare the global patterns of gene expression for the reference Caenorhabditis elegans strain (N2) grown at 15oC, 20oC, and 25oC on two different diets, Escherichia coli and Bacillus subtilis. When C. elegans were fed E. coli and the growth temperature was increased, we observed an enhancement of defense response pathways and down-regulation of genes associated with metabolic functions. However, when C. elegans were fed B. subtilis and the growth temperature was increased, the nematodes exhibited a decrease in defense response pathways and an enhancement of expression of genes associated with metabolic functions. Our results show that C. elegans undergo significant metabolic and defense response changes when the maintenance temperature fluctuates within the physiologically accepted experimental range and that the degree of pathogenicity of the bacterial diet can further alter the worm transcriptome. Overall design: C. elegans mRNA profiles at different temperatures and feeding in six samples, three replicates per sample. Deep sequencing in Illumina HiSeq2500.
Effect of the diet type and temperature on the <i>C. elegans</i> transcriptome.
Transcriptional profiling of human acute myeloid leukemia cells lines HEL and SET2 transduced with an IGF1R shRNA and miR-125a sponge.
Loss of the proteostasis factor AIRAPL causes myeloid transformation by deregulating IGF-1 signaling.
Specimen part, Cell line, TreatmentView Samples
Transcriptome analysis of a population of wild type animals and lsm-1 mutants at L3 stage Overall design: lsm-1(tm3585) mutants were backcrossed three times with wild type N2 animals. lsm-1 mutants and N2 animals were grown for 26 hours at 25C from a synchronized L1 population.
Cytoplasmic LSM-1 protein regulates stress responses through the insulin/IGF-1 signaling pathway in Caenorhabditis elegans.
Study on differential gene expression and splicing between wildtype and clock mutants. This study is part of a comparative analysis of the role of Protein Methyltransferase 5 in the regulation of transcriptional and post-transcriptional processes simultaneously in Arabidopsis and Drosophila.
A methyl transferase links the circadian clock to the regulation of alternative splicing.
Specimen partView Samples
In this report, we describe a successful protocol for isolating and expression-profiling live fluorescent- protein-labelled neurons from zebrafish embryos. As a proof-of-principle for this method, we FAC-sorted and RNA-profiled GFP-labelled spinal CiA interneurons and compared the expression profile of these cells to those of post-mitotic spinal neurons in general and to all trunk cells. We show that RNA of sufficient quality and quantity to uncover both expected and novel transcription profiles via Affymetrix microarray analysis can be extracted from 5,700 to 20,000 FAC-sorted cells. As part of this study, we also further confirm the genetic homology of mammalian and zebrafish V1 interneurons, by demonstrating that zebrafish V1 cells (CiAs) express genes that encode for the transcription factors Lhx1a and Lhx5. This protocol for dissociating, sorting and RNA-profiling neurons from organogenesis-stage zebrafish embryos should also be applicable to other developing organs and tissues and potentially other model organisms.
RNA profiling of FAC-sorted neurons from the developing zebrafish spinal cord.
Age, Specimen partView Samples
We have used the citrus GeneChip array (GPL5731) to survey the transcription profiles of sweet orange in response to the bacterial pathogens Xanthomonas axonopodis pv. citri (Xac) and Xanthomonas axonopodis pv. aurantifolii (Xaa). Xac is the causal agent of the citrus canker disease on a wide range of citrus species, including sweet oranges (Citrus sinensis). On the other hand, Xaa is pathogenic to Mexican lime (Citrus aurantifolia) only, and in sweet orange it triggers a defense response. In order to identify the genes induced during the defense response (Xaa-responsive genes) or citrus canker development (Xac-responsive genes), we conducted microarrays hybridization experiments at 6 and 48 hours after bacterial infiltration (habi). The analysis revealed that genes commonly modulated by Xac and Xaa are associated with basal defenses normally triggered by pathogen-associated molecular patterns, including those involved in reactive oxygen species production and lignification. Significantly, Xac-infected leaves showed considerable changes in the transcriptional profiles of defense-, cell wall-, vesicle trafficking- and cell growth-related genes between 6 and 48 habi. This is consistent with the notion that Xac suppresses host defenses near the beginning of the infection and simultaneously changes the physiological status of the host to promote cell enlargement and division. Finally, Xaa triggered a MAP kinase signaling pathway involving WRKY and ethylene-responsive transcriptional factors known to activate downstream defense genes.
Transcriptional analysis of the sweet orange interaction with the citrus canker pathogens Xanthomonas axonopodis pv. citri and Xanthomonas axonopodis pv. aurantifolii.
No sample metadata fieldsView Samples
Myofibroblast is a specific type of mesenchymal cell characterized by synthesis of extracellular matrix and contractile activity. While it serves a beneficial function during tissue wound healing under physiological conditions, it can cause devastating damage to organs afflicted with fibrosis. Myofibroblasts are also present in tumor stroma and contribute actively to tumor growth and spreading. Chicken embryo dermal myofibroblasts (CEDM) represent a novel ex vivo model suitable for the analysis of myofibroblastic phenotype as they show strongly pronounced, uniform and self-sustained myofibroblastic phenotype that is stable in time. As myofibroblastic differentiation is controlled chiefly by TGF-beta signaling, the understanding of the differentiation program entails the determination of TGF-beta-regulated genes. To achieve such a goal, we performed oligonucleotide microarray analysis of CEDM cells treated with a selective TGFBR1 kinase inhibitor. Genes reported previously to be under the control of TGF-beta signaling in mammalian cells appeared among the affected genes also in CEDM cells and many so far unknown TGF-beta targets were revealed.
Molecular analysis of the TGF-beta controlled gene expression program in chicken embryo dermal myofibroblasts.
Specimen part, TreatmentView Samples
Eight healthy human subjects were enrolled in a 6-day simulated shift work protocol. Blood samples were collected during the two 24-hour measurement periods. Blood samples were collected every 4 hours during both measurement periods. Subjects entered the lab on Day 1. At the start of Day 2, the first 24-hour measurement period was started. Subjects slept according to their habitual sleep/wake schedule, followed by a 16-hour constant posture procedure. On days 3-6, the sleep period was delayed by 10 hours. Following the third night on this schedule, subjects underwent another 24-hour measurement period. During both measurement periods, 7 blood samples were collected and PBMCs were isolated. mRNA was extracted, labelled, and hybridized to microarrays.
Simulated night shift work induces circadian misalignment of the human peripheral blood mononuclear cell transcriptome.