Investigating neuronal and photoreceptor regeneration in the retina of zebrafish has begun to yield insights into both the cellular and molecular means by which this lower vertebrate is able to repair its central nervous system. However, knowledge about the signaling molecules in the local microenvironment of a retinal injury and the transcriptional events they activate during neuronal death and regeneration is still lacking. To identify genes involved in photoreceptor regeneration, we combined light-induced photoreceptor lesions, laser-capture microdissection (LCM) of the outer nuclear layer (ONL) and analysis of gene expression to characterize transcriptional changes for cells in the ONL as photoreceptors die and are regenerated. Using this approach, we were able to characterize aspects of the molecular signature of injured and dying photoreceptors, cone photoreceptor progenitors and microglia within the ONL. We validated changes in gene expression and characterized the cellular expression for three novel, extracellular signaling molecules that we hypothesize are involved in regulating regenerative events in the retina.
Identification of the molecular signatures integral to regenerating photoreceptors in the retina of the zebra fish.
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View SamplesIn the retina of adult teleosts, stem cells are sustained in two specialized niches: the ciliary marginal zone (CMZ) and the microenvironment surrounding adult Mller glia. Recently, Mller glia were identified as the regenerative stem cells in the teleost retina. Secreted signaling molecules that regulate neuronal regeneration in the retina are largely unknown. In a microarray screen to discover such factors, we identified midkine-b (mdkb). Midkine is a highly conserved heparin-binding growth factor with numerous biological functions. The zebrafish genome encodes two distinct midkine genes: mdka and mdkb. Here, we describe the cellular expression of mdka and mdkb during retinal development and the initial, proliferative phase of photoreceptor regeneration. The results show that in the embryonic and larval retina mdka and mdkb are expressed in stem cells, retinal progenitors and neurons in distinct patterns that suggest different functions for the two molecules. Following the selective death of photoreceptors in the adult, mdka and mdkb are co-expressed in horizontal cells and proliferating Mller glia and their neurogenic progeny. These data reveal that Mdka and Mdkb are signaling factors present in the retinal stem cell niches in both embryonic and mature retinas, and that their cellular expression is actively modulated during retinal development and regeneration.
Cellular expression of midkine-a and midkine-b during retinal development and photoreceptor regeneration in zebrafish.
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View SamplesExercise training improves whole body glucose homeostasis through effects largely attributed to adaptations in skeletal muscle; however, training also affects other tissues including adipose tissue. To determine if exercise-induced adaptations to adipose tissue contribute to training-induced improvements in glucose homeostasis, subcutaneous white adipose tissue (scWAT) from trained or sedentary donor mice was transplanted into the visceral cavity of sedentary recipients. Remarkably, nine days post-transplantation, mice receiving trained scWAT had improved glucose tolerance and enhanced insulin sensitivity compared to mice transplanted with sedentary scWAT or sham-treated mice. Mice transplanted with trained scWAT had increased insulin-stimulated glucose uptake in tibialis anterior and soleus muscles and brown adipose tissue, suggesting that the transplanted scWAT exerted endocrine effects. Furthermore, the deleterious effects of high-fat feeding on glucose tolerance and insulin sensitivity were completely reversed if high-fat fed recipient mice were transplanted with trained scWAT. In additional experiments, voluntary exercise training by wheel running for only 11 days resulted in profound changes in scWAT including increased expression of 1550 genes involved in numerous cellular functions, including metabolism. Exercise training causes adaptations to scWAT that elicit metabolic improvements in other tissues, demonstrating a previously unrecognized role for adipose tissue in the beneficial effects of exercise on systemic glucose homeostasis.
A novel role for subcutaneous adipose tissue in exercise-induced improvements in glucose homeostasis.
Sex, Age, Specimen part
View SamplesRNA-seq of UPMM3 with restoration of BAP1 and BAP1 mutant proteins. Cell line UPMM3 contains a frameshift mutation in BAP1. Overall design: RNA-seq of UPMM3 with restoration of BAP1 and BAP1 mutant proteins
GNA11 Q209L Mouse Model Reveals RasGRP3 as an Essential Signaling Node in Uveal Melanoma.
Cell line, Subject
View SamplesThe molecular mechanism by which lncRNAs derived from the promoter region where the transcriptional machinery is assembled regulate the expression of neighboring genes during cell differentiation is largely unknown. Myogenesis process has been studied as a model of cell differentiation. Using this model, we found a novel lncRNA, Myoparr, expressed from the promoter region of myogenin gene, one of the regulators of myogenesis. We show that Myoparr regulates the expression of myogenin in vitro and in vivo. In addition, we identified Ddx17 and hnRNPK as Myoparr-binding-proteins. We compared the Transcriptome profiles of C2C12 cells (mouse myoblast cell line) with or without siRNAs against myogenin, Myoparr, Ddx17, and hnRNPK during myogenesis.
Data describing the effects of depletion of <i>M</i><i>yoparr</i>, <i>myogenin</i>, <i>Ddx17</i>, and <i>hnRNPK</i> in differentiating C2C12 cells.
Specimen part, Cell line
View SamplesA promoter associated lncRNA Myoparr is involved in the regulation of skeletal muscle atrophy caused by denervation. However, the molecular mechanism by which Myoparr regulates the expression of downstream genes in skeletal muscle tissue is largely unknown. Thus, we compared the Transcriptome profiles of denervated tibialis anterior muscles transfected with control or Myoparr shRNA.
Long Non-Coding RNA <i>Myoparr</i> Regulates GDF5 Expression in Denervated Mouse Skeletal Muscle.
Sex, Specimen part, Cell line, Treatment
View SamplesDuring translation elongation, the ribosome ratchets along its mRNA template, incorporating each new amino acid and translocating from one codon to the next. The elongation cycle requires dramatic structural rearrangements of the ribosome. We show here that deep sequencing of ribosome-protected mRNA fragments reveals not only the position of each ribosome but also, unexpectedly, its particular stage of the elongation cycle. Sequencing reveals two distinct populations of ribosome footprints, 28-30 nucleotides and 20-22 nucleotides long, representing translating ribosomes in distinct states, differentially stabilized by specific elongation inhibitors. We find that the balance of small and large footprints varies by codon and is correlated with translation speed. The ability to visualize conformational changes in the ribosome during elongation, at single-codon resolution, provides a new way to study the detailed kinetics of translation and a new probe with which to identify the factors that affect each step in the elongation cycle. Overall design: Ribosome profiling, or sequencing of ribosome-protected mRNA fragments, in yeast. We assay ribosome footprint sizes and positions in three conditions: untreated yeast (3 replicates) and yeast treated with translation inhibitors cycloheximide (2 replicates) and anisomycin (2 biological replicates, one technical replicate). We also treat yeast with 3-aminotriazole to measure the effect of limited histidine tRNAs on ribosome footprint size and distribution (two treatment durations).
Distinct stages of the translation elongation cycle revealed by sequencing ribosome-protected mRNA fragments.
Cell line, Treatment, Subject
View SamplesSTRRIDE is an exercise intervention study of different doses and intensities in overweight women and men with the metabolic syndrome. We profiled biopsies from 3 female and 3 male STRRIDE subjects in the high exercise group (2,200 kCal/wk). Muscle biopsies were profiled at entry (0h), and after 9 months of aerobic training (24 hrs post-last bout, 96 hrs post last bout, and 336h (14 days) de-training). Included also are pilot expression data from 3 male subjects.
Exercise training increases electron and substrate shuttling proteins in muscle of overweight men and women with the metabolic syndrome.
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View SamplesTranscriptomes of mouse embryonic autopods were generated detecting expression of approximately 26179 transcripts in the developing forelimb or hindlimb autopods, representing about 58 % of the probe sets on MOE-430 A/B GeneChip. Three biological replicate array experiments were finished for each condition and MAS5.0 signal were used to do data analysis. Forty-four transcripts with expression differences higher than 2-fold were detected(T test, P<0.05), including Tbx4, Tbx5, Hoxc10 and Pitx1 which were previously shown to be differentially expressed in developing forelimb and hindlimb bud by in situ hybridization and SAGE study (Margulies 2001). RTPCR and in situ experiments confirmed several top differentially expressed genes which were newly discovered by our experiments. Vast amount of transcripts and its family members such as Bmp, Fgf, Epha, Wnt, T-box and Hox families detected to be highly expressed or differentially expressed in developing autopods, suggesting that the complexity of transcriptomes of developing autopods and dynamic differential expression and differential combinations of gene expression signals in the developing limb tissue contributes to differences in forelimb versus hindlimb patterning. The differentially expressed genes are the essential factors for morphological diversification of developing limb structures.
Transcriptome analysis of the murine forelimb and hindlimb autopod.
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View SamplesTo explore gene expression profiles of cells sensitive to necrosis (such as L929 cells) and those sensitive to apoptosis (such as NIH3T3 cells), we conducted expression microarray analysis of L929 cells and NIH3T3 cells.
Identification of a molecular signaling network that regulates a cellular necrotic cell death pathway.
No sample metadata fields
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