To better understand the mechanistic basis of aging and its relationship with retinal degeneration, we examined gene expression changes in aging rod photoreceptors. Rod photoreceptor cell death is a feature of normal retinal aging and is accelerated in many retinal degenerative diseases, including AMD, the leading cause of untreatable adult blindness in the United States and other western countries. To our knowledge, the examination of age-related gene expression changes in a specific neuronal cell-type is novel, and it has allowed us to identify significant age-related changes with better resolution than is possible with whole retina samples. We used flow cytometry and a transgenic mouse with GFP-tagged rod photoreceptors to purify this specific cell population, and gene expression changes were evaluated at three time points using microarrays and quantitative RT-PCR. Our results suggest that aging is progressive, beginning even in young adult mice. Although rod photoreceptors are highly specialized neurons, our analyses revealed changes in consensus pathways of aging, including oxidative phosphorylation and stress responses affecting transcription and inflammation. In addition, we identified stress response processes that may be especially relevant for the aging retina and retinal diseases, such as angiogenesis and nuclear receptor signaling pathways that affect retinoid and lipid metabolism.
Distinct signature of altered homeostasis in aging rod photoreceptors: implications for retinal diseases.
Age, Specimen part
View SamplesThe study aims to define gene expression changes associated with mithramycin treatment of Ewing Sarcoma cell lines.
Identification of an inhibitor of the EWS-FLI1 oncogenic transcription factor by high-throughput screening.
Cell line, Treatment
View SamplesThis dataset contains Affymetrix Mouse Genome 430 2.0 Array data obtained from K7M2 cells over-expressing ezrinT567A and the wild-type
Dysregulation of ezrin phosphorylation prevents metastasis and alters cellular metabolism in osteosarcoma.
Cell line
View SamplesDetermination of gene expression changes in hindlimb muscle (gastrocnemius/soleus) of mdx (dystrophin-deficient) mice at postnatal ages 7, 14, 23, 28, 56, and 112.
Dissection of temporal gene expression signatures of affected and spared muscle groups in dystrophin-deficient (mdx) mice.
No sample metadata fields
View SamplesDetermination of gene expression changes in extraocular muscle of mdx (dystrophin-deficient) mice at postnatal ages 14, 28, 56, and 112 days. 3 independent replicates/age/strain.
Dissection of temporal gene expression signatures of affected and spared muscle groups in dystrophin-deficient (mdx) mice.
No sample metadata fields
View SamplesRhesus monkey extraocular muscle. Data set includes: (a) whole medial and lateral rectus muscle and (b) global and orbital muscle layers separately microdissected using a Leica LSM. All samples were expression profiled here using the Affymetrix human U133 A&B arrays. Data form part of publication: Investigative Ophthalmology and Visual Science 45, 2004.
Genome-wide transcriptional profiles are consistent with functional specialization of the extraocular muscle layers.
No sample metadata fields
View SamplesStaphylococcus aureus enterotoxins cause debilitating systemic inflammatory responses, but how they spread systemically and trigger cascading inflammation is unclear. Here, we showed in mice that after inhalation, Staphylococcus aureus enterotoxin A rapidly entered the bloodstream and induced T cells to orchestrate systemic recruitment of inflammatory monocytes and neutrophils. To study the mechanism used by specific T cells that mediate this process, a systems approach revealed inducible and non-inducible pathways as potential targets. It was found that TNF induced neutrophil entry into the peripheral blood, while CD28 signaling, but not TNF, was needed for chemotaxis of inflammatory monocytes into blood and lymphoid tissue. However, both pathways triggered local recruitment of neutrophils into lymph nodes. Thus, our findings revealed a dual mechanism of monocyte and neutrophil recruitment by T cells relying on overlapping and non-overlapping roles for the non-inducible costimulatory receptor CD28 and the inflammatory cytokine TNF. During sepsis, there might be clinical value in inhibiting CD28 signaling to decrease T cell-mediated inflammation and recruitment of innate cells while retaining bioactive TNF to foster neutrophil circulation. Overall design: The purpose of this analysis was to determine changes in gene expression in SEA-specific Vß3+ T cells and bystander T Vß14+ cells 40 min after SEA or vehicle inhalation.The samples were collected from three independent experiments with total n=3 per group. Three groups of samples were prepared: vehicle Vß3+ T cells, SEA Vß3+ T cells, and SEA Vß14+ T cells.
TNF and CD28 Signaling Play Unique but Complementary Roles in the Systemic Recruitment of Innate Immune Cells after Staphylococcus aureus Enterotoxin A Inhalation.
Specimen part, Cell line, Subject
View SamplesRod and cone photoreceptors in mammalian retina are generated from common pool(s) of neuroepithelial progenitors. NRL, CRX and NR2E3 are key transcriptional regulators that control photoreceptor differentiation. Mutations in NR2E3, a rod-specific orphan nuclear receptor, lead to loss of rods, increased density of S-cones, and supernormal S-cone-mediated vision in humans. To better understand its in vivo function, NR2E3 was expressed ectopically in the Nrl-/- retina, where post-mitotic precursors fated to be rods develop into functional S-cones similar to the human NR2E3 disease. Expression of NR2E3 in the Nrl-/- retina completely suppressed cone differentiation and resulted in morphologically rod-like photoreceptors, which were not functional. Gene profiling of FACS-purified photoreceptors confirmed the role of NR2E3 as a strong suppressor of cone genes and an activator of a subset of rod genes (including rhodopsin) in vivo. Ectopic expression of NR2E3 in cone precursors and differentiating S-cones of wild type retina also generates rod-like cells. The dual regulatory function of NR2E3 is not dependent upon the presence of NRL and/or CRX, but on the timing and level of its expression. Our studies reveal a critical role of NR2E3 in establishing functional specificity of post-mitotic photoreceptor precursors during retinal neurogenesis.
In vivo function of the orphan nuclear receptor NR2E3 in establishing photoreceptor identity during mammalian retinal development.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Distinctive morphological and gene/protein expression signatures during myogenesis in novel cell lines from extraocular and hindlimb muscle.
No sample metadata fields
View SamplesDetermination of gene expression changes in extraocular muscle of mdx (dystrophin-deficient) mice at postnatal ages 7, 14, 23, 28, 56, and 112 days. 3 independent replicates/age/strain. Data form part of publication: Human Molecular Genetics 13:257-269, 2004.
Temporal gene expression profiling of dystrophin-deficient (mdx) mouse diaphragm identifies conserved and muscle group-specific mechanisms in the pathogenesis of muscular dystrophy.
No sample metadata fields
View Samples