During early vertebrate development, a large number of noncoding RNAs are maternally inherited or expressed upon activation of zygotic transcription. The exact identity, expression levels, and function during early vertebrate development for most of these noncoding RNAs remains largely unknown. miRNAs (microRNAs) and piRNAs (piwi-interacting RNAs) are two classes of small non-coding RNAs that play important roles in gene regulation during early embryonic development. Here, we utilized Illumina next generation sequencing technology to determine temporal expression patterns for both miRNAs and piRNAs during four distinct stages of early vertebrate development using zebrafish as a model system. For miRNAs, the expression patterns for 192 known miRNAs and 12 novel miRNAs within 123 different miRNA families were determined. Significant sequence variation was observed at the 5'' and 3'' ends of miRNAs with a large number of extra nucleotides added in a non-template directed manner. We also identified a large and diverse set of piRNAs expressed during early development, far beyond that expected if piRNA expression is restricted to germ cells. Our analyses represent the deepest investigation to date of small RNA expression during early vertebrate development and suggest important novel functions for small RNAs during embryogenesis. Overall design: Identify the expression of small RNAs in zebrafish embryos of four different developmental stages using high through-put sequencing
Transcriptome-wide analysis of small RNA expression in early zebrafish development.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Negative energy balance and hepatic gene expression patterns in high-yielding dairy cows during the early postpartum period: a global approach.
No sample metadata fields
View SamplesMost dairy cows suffer uterine microbial contamination postpartum. Persistent endometritis often develops, associated with reduced fertility. We used a model of differential feeding and milking regimes to produce cows in differing negative energy balance (NEB) status in early lactation.
Negative energy balance alters global gene expression and immune responses in the uterus of postpartum dairy cows.
Age, Specimen part
View SamplesIn high yielding dairy cows the liver undergoes extensive physiological and biochemical changes during the early postpartum period in an effort to re-establish metabolic homeostasis and to counteract the adverse effects of negative energy balance (NEB). These adaptations are likely to be mediated by significant alterations in hepatic gene expression. To gain new insights into these events an EB model was created using differential feeding and milking regimes to produce two groups of cows with either a mild (MNEB) (n=5) or severe NEB (SNEB) (n=6) status. Cows were slaughtered and liver tissues collected on days 6-7 of the first follicular wave postpartum. Using an Affymetrix 23k oligonucleotide bovine array to determine global gene expression in hepatic tissue of these cows, a total of 416 genes (189 up- and 227 down-regulated) were found to be altered by SNEB. Network analysis using Ingenuity Pathway Analysis revealed that SNEB was associated with widespread changes in gene expression classified into 36 gene networks including those associated with lipid metabolism, connective tissue development and function, cell signalling, cell cycle and metabolic diseases. Severe NEB cows displayed reduced expression of transcription activators and signal transducers that regulate the expression of genes and gene networks associated with cell signalling and tissue repair. These alterations are linked with increased expression of abnormal cell cycle and cellular proliferation associated pathways. This study provides new information and insights on the effect of SNEB on gene expression in high yielding Holstein Friesian dairy cows in the early postpartum period.
Negative energy balance and hepatic gene expression patterns in high-yielding dairy cows during the early postpartum period: a global approach.
No sample metadata fields
View SamplesGeminin is a small nucleoprotein that neuralizes ectoderm in the Xenopus embryo. Geminin promotes neural fate acquisition of mouse embryonic stem cells: Geminin knockdown during neural fate acquisition decreased expression of neural precursor cell markers (Pax6, Sox1), while increasing expression of Pitx2, Lefty1 and Cited2, genes involved in formation of the mouse node. Here we differentiated mouse embryonic stem cells into embryoid bodies to study Geminin's ability to repress primitive streak mesendoderm fate acquisition. We used microarrays to define the sets of genes that are regulated by Geminin during cell fate acquisition in embryoid bodies, using Dox-inducible Geminin knockdown or overexpression mouse embryonic stem cell lines.
Geminin restrains mesendodermal fate acquisition of embryonic stem cells and is associated with antagonism of Wnt signaling and enhanced polycomb-mediated repression.
Specimen part
View SamplesFormation of the complex vertebrate nervous system begins when pluripotent cells of the early embryo are directed to acquire a neural fate. Although cell intrinsic controls play an important role in this process, the molecular nature of this regulation is not well defined. Here we assessed the role for Geminin, a nuclear protein expressed in embryonic cells, in neural fate acquisition from mouse embryonic stem (ES) cells. While Geminin knockdown does not affect the ability of ES cells to maintain or exit pluripotency, we found that it significantly impairs their ability to acquire a neural fate. Conversely, Geminin overexpression promotes neural gene expression, even in the presence of growth factor signaling that antagonizes neural transcriptional responses. These data demonstrate that Geminins activity contributes to mammalian neural cell fate acquisition. We investigated the mechanistic basis of this phenomenon and found that Geminin maintains a hyperacetylated and open chromatin conformation at neural genes. Interestingly, recombinant Geminin protein also rapidly alters chromatin acetylation and accessibility even when Geminin is combined with nuclear extract and chromatin in vitro. These findings define a novel activity for Geminin in regulation of chromatin structure. Together, these data support a role for Geminin as a cell intrinsic regulator of neural fate acquisition that promotes expression of neural genes by regulating chromatin accessibility and histone acetylation.
Geminin promotes neural fate acquisition of embryonic stem cells by maintaining chromatin in an accessible and hyperacetylated state.
Specimen part, Treatment
View SamplesRecent studies have shown that circular RNAs (circRNAs) are abundant, widely expressed in mammals, and can display cell-type specific expression. However, how production of circRNAs is regulated and their precise biological function remains largely unknown. To study how circRNAs might be regulated during colorectal cancer progression, we used three isogenic colon cancer cell lines that differ only in KRAS mutation status. Cellular RNAs from the parental DLD-1 cells that contain both wild-type and G13D mutant KRAS alleles and isogenically-matched derivative cell lines, DKO-1 (mutant KRAS allele only) and DKs-8 (wild-type KRAS allele only) were analyzed using RNA-Seq. We developed a bioinformatics pipeline to identify and evaluate circRNA candidates from RNA-Seq data. Hundreds of high-quality circRNA candidates were identified in each cell line. Remarkably, circRNAs were significantly down-regulated at a global level in DLD-1 and DKO-1 cells compared to DKs-8 cells, indicating a widespread effect of mutant KRAS on circRNA abundance. This finding was confirmed in two independent colon cancer cell lines HCT116 (KRAS mutant) and HKe3 (KRAS WT). In all three cell lines, circRNAs were also found in secreted extracellular-vesicles, and circRNAs were more abundant in exosomes than cells. Our results suggest that circRNAs may serve as promising cancer biomarkers. Overall design: RNAseq deep sequencing for both cell and exosome mRNAs
Circular RNAs are down-regulated in KRAS mutant colon cancer cells and can be transferred to exosomes.
No sample metadata fields
View SamplesIncreased energy demands to support lactation, coupled with lowered feed intake capacity results in negative energy balance (NEB) and is typically characterized by extensive mobilization of body energy reserves in the early postpartum dairy cow. The catabolism of stored lipid leads to an increase in the systemic concentrations of nonesterified fatty acids (NEFA) and -hydroxy butyrate (BHB). Oxidation of NEFA in the liver result in the increased production of reactive oxygen species and the onset of oxidative stress and can lead to disruption of normal metabolism and physiology. The immune system is depressed in the peripartum period and early lactation and dairy cows are therefore more vulnerable to bacterial infections causing mastitis and or endometritis at this time. A bovine Affymetrix oligonucleotide array was used to determine global gene expression in the spleen of dairy cows in the early postpartum period. Spleen tissue was removed post mortem from five severe NEB (SNEB) and five medium NEB (MNEB) cows 15 days postpartum.SNEB increased systemic concentrations of NEFA and BHB, and white blood cell and lymphocyte numbers were decreased in SNEB animals. A total of 545 genes were altered by SNEB. Network analysis using Ingenuity Pathway Analysis revealed that SNEB was associated with NRF2-mediated oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress, natural killer cell signaling, p53 signaling, downregulation of IL-15, BCL-2, and IFN- ; upregulation of BAX and CHOP and increased apoptosis with a potential negative impact on innate and adaptive immunity.
Pleiotropic effects of negative energy balance in the postpartum dairy cow on splenic gene expression: repercussions for innate and adaptive immunity.
No sample metadata fields
View SamplesExpression profile of human donor lungs that have developed primary graft dysfunction (PGD) after lung transplantation and those that have not.
Expression profiling of human donor lungs to understand primary graft dysfunction after lung transplantation.
No sample metadata fields
View SamplesThe Lim1 gene has essential functions during several stages of kidney development. In particular, a tissue specific knockout in the early metanephric mesenchyme results in the formation of the earliest nephron precursor, the renal vesicle, but failure of this structure to progress to the next stage, the comma shaped body. To better understand the molecular nature of this developmental arrest we used a laser capture microdissection-microarray strategy to examine the perturbed gene expression pattern of the mutant renal vesicles. Among the genes found differently expressed were Chrdl2, an inhibitor of BMP signaling, the pro-apoptotic factor Bmf, as well as myob5, an atypical myosin which modulates chemokine and transferring signaling, and pdgfr1, which is important in epithelial folding. Of particular interest, the microarray data indicated that the Dkk1 gene, which encodes an inhibitor of Wnt signaling, was downregulated nine fold in mutants. This was confirmed by in situ hybridizations. It is interesting to note that Lim1 and Dkk1 mutant mice have striking similarities in phenotype. These results suggest that the Dkk1 gene might be a key downstream effector of Lim1 function.
Laser capture-microarray analysis of Lim1 mutant kidney development.
No sample metadata fields
View Samples