Project description:We performed a microarray screening of adult rat retinas to identify genes that could show and up- or down-regulation due to exposure to light. This study was performed using ex-vivo retinas collected from adult Long Evans rats that were exposed to light (1000 Lux), or were left in dark as control. All experiments were performed at the same hour, so that the contribution from the circadian rhythm would not affect the observations. The hours to which the experiment was performed were at 7am (always in dark), 10am (under 1000 lux) and as control 10am (always kept in dark), 1pm (under 1000 Lux) and 1pm (Always in dark).
Project description:We performed a microarray screening of adult rat retinas to identify genes that could show and up- or down-regulation due to exposure to light.
Project description:Transcriptional profiles were compared between dark adapted and light damaged BALBc (albino) mouse retinas. Experiment Overall Design: BALBc mice were dark adapted for one week. To produce light damage a subset of the mice were then exposed to 6,000 lux white fluorescent light for 6 hours. Retinas were collected for RNA extraction 24 hours after light damage.
Project description:Purpose: In the C57BL/6J mouse retina, hyperoxia-induced degeneration of photoreceptors shows strong regional variation, beginning at a locus ~0.5mm inferior to the optic disc. To identify gene expression differences that might underlie this variability in vulnerability, we have used microarray techniques to describe regional (superior-inferior) variations in gene expression in the retina. Methods: Young adult C57BL/6J mice raised in dim cyclic illumination (12h 5lux, 12h darkness) were exposed to hyperoxia (75% oxygen for 2w). Retinas were collected from hyperoxia-exposed and control animals without fixation, and divided into superior and inferior halves. RNA was extracted from each sample, purified and hybridised to mouse 1.0 ST arrays (Affymetrix). The consistency of the microarray results was assessed with quantitative PCR for selected genes. Expression data were analysed to identify genes and ncRNAs whose differential expression between superior and inferior retina could be associated with relative vulnerability to hyperoxia.
Project description:To obtain an unbiased, thorough understanding of the biological pathways implicated in atRAL-induced cytotoxicity and PDE inhibitor-mediated cytoprotection, we performed a mass spectrometry-based quantitative proteomic analysis of ARPE19 cells, using stable-isotope labeling of amino acids in cell culture (SILAC). We identified differentially expressed proteins in ARPE19 cells exposed to stress (60 μM atRAL or 5 mM H2O2) in the absence or presence of PDE inhibitor (10 μM BAY 60-7550, rolipram, or BC11-38), relative to vehicle-treated controls. We also performed combined label-free mass spectrometry-based quantitative proteomic and phosphoproteomic analyses of retinas from the Abca4-/-Rdh8-/- double-knockout (dKO) light-sensitive mouse model of photoreceptor degeneration. First, we identified differentially expressed proteins in retinas exposed to bright-light stress (10,000 lux for 30 min) relative to unstressed controls. Next, we identified differentially expressed proteins in PDE inhibitor-treated mice (2 mg/kg intraperitoneal BAY 60-7550, rolipram, or BC11-38) exposed to stress relative to DMSO vehicle-treated controls. Altogether, these analyses provided insights into the proteomic and phosphoproteomic changes induced by stress and modulated by PDE-inhibitor therapy.
Project description:Human organoids recapitulating the cell-type diversity and function of their target organ are valuable for basic and translational research. We developed light-sensitive human retinal organoids with multiple nuclear and synaptic layers, and functional synapses. We sequenced the RNA of 285,441 single cells from these organoids at seven developmental time points and from the periphery, fovea, pigment epithelium and choroid of light-responsive adult human retinas.
Project description:Human organoids recapitulating the cell-type diversity and function of their target organ are valuable for basic and translational research. We developed light-sensitive human retinal organoids with multiple nuclear and synaptic layers, and functional synapses. We sequenced the RNA of 285,441 single cells from these organoids at seven developmental time points and from the periphery, fovea, pigment epithelium and choroid of light-responsive adult human retinas.