To identify genes regulated by Rx3 during optic vesicle morphogenesis, adult zebrafish carriers of a null rx3 mutation were mated. Before 13 hours post fertilization (hpf), the earliest time point at which optic vesicle evagination phenotypes could be reliably detected, offspring were phenotypically separated into pools comprising of mutants with an absence of optic vesicles or siblings exhibiting a wild-type phenotype. Three replicates of pooled RNA samples from 13 hpf eyeless mutants (rx3-/-) or phenotypically wild-type siblings (rx3+/+ or rx3+/-), and one replicate of 13 hpf wild-type zebrafish larva were collected for whole transcriptome sequencing. Overall design: Whole transcriptome sequencing (RNA-seq) was performed on zebrafish rx3-/- mutants, wild-type siblings and wild-type AB strains at 13 hpf
Genes and signaling networks regulated during zebrafish optic vesicle morphogenesis.
No sample metadata fieldsView Samples
TCDD increased expression of numerous differentiation specific genes and decreased expression of numerous genes involved in mitochondrial health and redox homeostasis
2,3,7,8-Tetrachlorodibenzo-p-dioxin-mediated production of reactive oxygen species is an essential step in the mechanism of action to accelerate human keratinocyte differentiation.
Specimen part, Cell lineView Samples
The detachment of epithelial cells, but not cancer cells, causes anoikis due to reduced energy production. Invasive tumor cells generate three splice variants of the metastasis gene osteopontin. The cancer-specific form osteopontin-c supports anchorage-independence through inducing oxidoreductases and upregulating intermediates/enzymes in the hexose monophosphate shunt, glutathione cycle, glycolysis, glycerol phosphate shuttle, and mitochondrial respiratory chain. Osteopontin-c signaling upregulates glutathione (consistent with the induction of the enzyme GPX-4), glutamine and glutamate (which can feed into the tricarboxylic acid cycle). Consecutively, the cellular ATP levels are elevated. The elevated creatine may be synthesized from serine via glycine and also supports the energy metabolism by increasing the formation of ATP. Metabolic probing with N-acetyl-L-cysteine, L-glutamate, or glycerol identified differentially regulated pathway components, with mitochondrial activity being redox dependent and the creatine pathway depending on glutamine. The effects are consistent with a stimulation of the energy metabolism that supports anti-anoikis. Our findings imply a synergism in cancer cells between osteopontin-a, which increases the cellular glucose levels, and osteopontin-c, which utilizes this glucose to generate energy. Overall design: mRNA profiles of MCF-7 cells transfected with osteopontin-a, osteopontin-c and vector control were generated by RNA-Seq, in triplicate, by Illumina HiSeq.
Energy metabolism during anchorage-independence. Induction by osteopontin-c.
No sample metadata fieldsView Samples
Cone photoreceptors are specialised sensory retinal neurons responsible for photopic vision, colour perception and visual acuity. Retinal degenerative diseases are a heterogeneous group of eye diseases in which the most severe vision loss typically arises from cone photoreceptor dysfunction or degeneration. Establishing a method to purify cone photoreceptors from retinal tissue can accelerate the identification of key molecular determinants that underlie cone photoreceptor development, survival and function. The work herein describes a new method to purify enhanced green fluorescent protein (EGFP)-labelled cone photoreceptors from adult retina of Tg(3.2TCP:EGFP) zebrafish. Electropherograms confirmed downstream isolation of high-quality RNA with RNA integrity number (RIN) >7.6 and RNA concentration >5.7 ng/l obtained from both populations. Reverse Transcriptase-PCR (RT-PCR) confirmed that the EGFP-positive cell populations express known genetic markers of cone photoreceptors that were not expressed in the EGFP-negative cell population. This work is an important step towards the identification of cone photoreceptor-enriched genes, protein and signalling networks responsible for their development, survival and function. In addition, this advancement facilitates the identification of novel candidate genes for inherited human blindness.
HDAC6 inhibition by tubastatin A is protective against oxidative stress in a photoreceptor cell line and restores visual function in a zebrafish model of inherited blindness.
Specimen partView Samples
Methamphetamine (Meth) seeking progressively increases after withdrawal (incubation of Meth craving), but the transcriptional mechanisms that contribute to this incubation are unknown. Here we used RNA-sequencing to analyze transcriptional profiles associated with incubation of Meth craving in central amygdala (CeA) and orbitofrontal cortex (OFC), two brain areas previously implicated in relapse to drug seeking. We trained rats to self-administer either saline (control condition) or Meth (10 days; 9 h/day, 0.1 mg/kg/infusion). Next, we collected brain tissue from CeA and OFC on withdrawal day 2 (when Meth seeking is low and non-incubated) and on day 35 (when Meth seeking is high and incubated), for subsequent RNA-sequencing. In CeA, we identified 10-fold more differentially expressed genes (DEGs) on withdrawal day 35 than day 2. These genes were enriched for several biological processes, including protein ubiquitination and histone methylation. In OFC, we identified many fewer expression changes than in CeA. Interestingly, there were more DEGs on withdrawal day 2 than on day 35. Several genes in OFC showed opposing expression changes on withdrawal day 2 (increase) when compared to withdrawal day 35 (decrease), which was further validated by qPCR. Our analyses highlight the CeA as a key region of transcriptional regulation associated with incubation of Meth seeking. In contrast, transcriptional regulation in OFC may contributes to Meth seeking during early withdrawal. Overall, these findings provide a unique resource of gene expression data for future studies examining transcriptional mechanisms in CeA that mediate Meth seeking after prolonged withdrawal. Overall design: Exp. 1 Genome-wide transcriptional profiling of CeA during incubation of Meth craving We performed intravenous surgeries on two groups of rats (total n=26) and trained them to self-administer either saline (n=12) or Meth (n=14) as described above in 2 independent runs. We performed live decapitation on withdrawal days 2 and 35, and collected CeA tissue for mRNA preparation. We used the extracted mRNA for library preparation and RNA-sequencing. We pooled tissue from two rats as one biological replicate. The number of biological replicates in each group was: Day 2: Saline=3, Meth=4; Day 35: Saline=3, Meth=3. Exp. 2 Genome-wide transcriptional profiling of OFC during incubation of Meth craving As above, two groups of rats (total n=32) were trained to self-administer saline (n=16) or Meth (n=16) in 2 independent runs. We performed live decapitation on withdrawal days 2 and 35, and collected OFC tissue for mRNA preparation. We used the extracted mRNA either for library preparation and RNA-sequencing or for cDNA synthesis and qPCR. We pooled tissue from two rats as one biological replicate. The number of biological replicates in each group was: Day 2: Saline=4, Meth=4; Day 35: Saline=4, Meth=4.
Genome-wide transcriptional profiling of central amygdala and orbitofrontal cortex during incubation of methamphetamine craving.
Specimen part, Cell line, Treatment, SubjectView Samples
The analysis of capped RNAs by massively parallel sequencing has identified a large number of previously unknown transcripts, some of which are small RNAs and others are 5 truncated forms of RefSeq genes. The latter may be generated by endonuclease cleavage or by stalling of Xrn1 at defined sites. With the exception of promoter-proximal transcripts the caps on all of these are added post-transcriptionally by a cytoplasmic capping enzyme complex that includes capping enzyme and a kinase that converts 5-monophosphate ends to a diphosphate capping substrate. We previously described a modified form of capping enzyme with dominant negative activity against cytoplasmic capping (DN-cCE). A tet-inducible form of this was used to identify substrates for cytoplasmic capping by treating cytoplasmic RNA from control and induced cells with and without Xrn1. Surviving RNA was analyzed on Affymetrix Human Exon 1.0 arrays and scored for changes in probe intensity as a function of its position on each RefSeq gene to derive a factor (alpha) that could be compared between sets. Notably, transcriptome-wide changes were not evident unless RNA was treated with Xrn1. This analysis identified 2,666 uncapped mRNAs in uninduced cells, 672 mRNAs that appeared in the uncapped pool in cells expressing DN-cCE, and 835 mRNAs that were in both populations. Changes in cap status of 10 re-capping targets and 5 controls were assessed by 3 independent measures; susceptibility to Xrn1, recovery with a biotin-tagged DNA primer after ligating a complementary RNA oligonucleotide to uncapped 5 ends, and binding or exclusion from a high affinity cap-binding matrix comprised of immobilized eIF4E and the corresponding binding domain of eIF4G.
Identification of cytoplasmic capping targets reveals a role for cap homeostasis in translation and mRNA stability.
Cell lineView Samples
Gene expression profiling of zebrafish early eye development on 3 to 5 days post fertilization (dpf)
Integrating multiple genome annotation databases improves the interpretation of microarray gene expression data.
Specimen partView Samples
Years after the discovery that Dicer is a key enzyme in gene-silencing, the role of its helicase domain remains enigmatic. Here we show that this domain is critical for accumulation of certain endogenous small interfering RNAs (endo-siRNAs) in C. elegans. The domain is required for the production of the direct products of Dicer, or primary endo-siRNAs, and consequently, affects levels of downstream intermediates, the secondary endo-siRNAs. Consistent with the role of endo-siRNAs in silencing, their loss correlates with an increase in cognate mRNA levels. We find that the helicase domain of Dicer is not required for microRNA (miRNA) processing, or RNA interference following exposure to exogenous double-stranded RNA. Comparisons of wildtype and helicase-defective strains using deep-sequencing analyses show that the helicase domain is required by a subset of annotated endo-siRNAs, in particular, those associated with the slightly longer 26 nucleotide small RNA species containing a 5' guanosine. Overall design: We reintroduced either wildtype Dicer, or Dicer harboring a mutation (K39A) in it''s helicase domain, into dcr-1(ok247) mutant worms via transgene rescue. We then used high-throughput sequencing to compare levels of small RNAs present in each of these strains.
Dicer's helicase domain is required for accumulation of some, but not all, C. elegans endogenous siRNAs.
Cell line, SubjectView Samples
Through Next Generation Sequencing (mRNA-Seq) of intracellular miRNAs in measles virus-stimulated B and CD4+ T cells isolated from high and low antibody responders to measles vaccination, we identified a set of B cell-specific miRNAs (e.g., miR-151a-5p, miR-223, miR-29, miR-15a-5p, miR-199a-3p, miR-103a, and miR-15a/16 cluster) associated with measles-specific antibody response after vaccination. No CD4+ T cell-specific miRNA expression differences between high and low antibody responders were found. DIANA tool was used for gene/target prediction and pathway enrichment analysis and this yielded several biological processes/pathways, including regulation of adherens junction proteins, Fc-receptor signaling pathway, phosphatidylinositol-mediated signaling pathway, growth factor signaling pathway/pathways, transcriptional regulation, apoptosis and virus-related processes, that were significantly associated with neutralizing antibody titers after measles vaccination. This study demonstrates that miRNA expression directly or indirectly influences humoral immunity to measles vaccination and suggests that B cell-specific miRNAs may potentially serve as predictive biomarkers of vaccine response. Overall design: Examination of miRNA expression differences in/between purified B and CD4+ T cells of high and low responders to measles vaccination.
Differential miRNA expression in B cells is associated with inter-individual differences in humoral immune response to measles vaccination.
Specimen part, SubjectView Samples
Deregulation of the transforming growth factor- (TGF) signaling pathway in epithelial ovarian cancer has been reported, but the precise mechanism underlying disrupted TGF signaling in the disease remains unclear. We performed chromatin immunoprecipitation followed by sequencing (ChIP-seq) to investigate genome-wide screening of TGF-induced SMAD4 binding in epithelial ovarian cancer. Following TGF stimulation of the A2780 epithelial ovarian cancer cell line, we identified 2,362 SMAD4 binding loci and 318 differentially expressed SMAD4 target genes. Comprehensive examination of SMAD4-bound loci, revealed four distinct binding patterns: 1) Basal; 2) Shift; 3) Stimulated Only; 4) Unstimulated Only. SMAD4-bound loci were primarily classified as either Stimulated only (74%) or Shift (25%), indicating that TGF-stimulation alters SMAD4 binding patterns in epithelial ovarian cancer cells compared to normal epithelial cells. Furthermore, based on gene regulatory network analysis, we determined that the TGF-induced SMAD4-dependent regulatory network was strikingly different in ovarian cancer compared to normal cells. Importantly, the TGF/SMAD4 target genes identified in the A2780 epithelial ovarian cancer cell line were predictive of patient survival, based on in silico mining of publically available patient data bases. In conclusion, our data highlight the utility of next generation sequencing technology to identify genome-wide SMAD4 target genes in epithelial ovarian cancer. The results link aberrant TGF/SMAD signaling to ovarian tumorigenesis. Furthermore, the identified SMAD4 binding loci, combined with gene expression profiling and in silico data mining of patient cohorts, may provide a powerful approach to determine potential gene signatures with biological and future translational research in ovarian and other cancers.
ChIP-seq defined genome-wide map of TGFβ/SMAD4 targets: implications with clinical outcome of ovarian cancer.
Cell line, TreatmentView Samples