Transcription profiling of rat small and large retinal ganglion cells
Ontology highlight
ABSTRACT: Different sub-types of ganglion cells existing in mammalian retinas possessing distinct function in processing the visual information. In primates, RGC are commonly divided into midget cells, which are relatively small, and parasol cells, with a larger soma size. Rodents also possess morphologically distinct populations, but their physiological properties are less characterized. The two types of mammalian RGCs differ in their response to pathological conditions such as retinal ischemia, diabetic retinopathy and glaucoma. In this work, we compared gene expression profiles of large (LRGCs) and small (SRGCs) ganglion cells isolated from rat retina in attempt to identify molecular determinants underlying differences in function and tolerance to stress. Experiment Overall Design: Rat RGCs retrogradely labeled with 4DI-10ASP were purified from freshly dissected retinas and subjected to fluorescent-activated cell sorting (FACS) in order to separate the SRGC and LRGC sub-populations. Actinomycin D was added to prevent new transcription during experimental procedures. Purified cells were used for RNA isolation. Following two rounds of linear amplification aRNA probes were hybridized with two-color Agilent Rat Genomic Oligo Arrays. We utilized the dye swap experimental design to eliminate the dye bias effects and make data from different experiments available for the cross-comparison.
Project description:We report the genome-wide RNA sequencing changes to isolated retinal ganglion cells (RGCs) from immunopanned embryonic day 18 (E18) and early postnatal (P5) wildtype mouse retinas. We report the transcriptomic change associated with RGCs in a survival and regenerative state, and use gene-set enrichment analysis (GSEA) to predict the upstream transcription factors likely regulating these observed changes.
Project description:Different sub-types of ganglion cells existing in mammalian retinas possessing distinct function in processing the visual information. In primates, RGC are commonly divided into midget cells, which are relatively small, and parasol cells, with a larger soma size. Rodents also possess morphologically distinct populations, but their physiological properties are less characterized. The two types of mammalian RGCs differ in their response to pathological conditions such as retinal ischemia, diabetic retinopathy and glaucoma. In this work, we compared gene expression profiles of large (LRGCs) and small (SRGCs) ganglion cells isolated from rat retina in attempt to identify molecular determinants underlying differences in function and tolerance to stress. Keywords: comparative hybridization
Project description:Mice lacking the beta 2 subunit (Chrnb2) of the neuronal nicotinic acetylcholine receptor display altered retinal waves and disorganized projections of the retinal ganglion cells to the lateral geniculate nucleus (LGN). mRNA populations from retinas and LGN from Chrnb2-/-and wild type (C57BL/6J) mice were compared at 4 days postnatal, when RGC segregation to the LGN begins in WT mice. Retinal mRNAs were also compared at adulthood. Using microarray hybridization, we identified transcripts which are differentially expressed between Chrnb2-/- and wild type animals in these two tissues at these two ages. mRNA was isolated from retina and LGN of three male littermates each of WT and Chrnb2-/- mice at P4. mRNA from retinas of two adult male littermates of each type was also examined.
Project description:Experimental ocular hypertension (IOP) induces senescence of retinal ganglion cells (RGCs) that mimicks events occurring in human glaucoma. An established transgenic p16-3MR mouse model in which the systemic administration of the small molecule ganciclovir (GCV) selectively kills p16INK4a-expressing cells was used to compare transcriptomes of retinas from IOP and control eyes in GCV-treated and non-treated mice, to investigate how experimental removal of senescent p16INK4a-positive cells impacts retinal cells in conditions resembling glaucoma.
Project description:We used gene microarray analysis to compare the global expression profile of genes involved in adaptation to exercise training in skeletal muscle from chronically strength/resistance trained (ST), endurance trained (ET) and untrained control subjects (Con). Resting skeletal muscle samples (~100mg) were obtained from the vastus lateralis of 20 subjects (Con n=7, ET n=7, ST n=6; trained groups >8 years specific training). Total RNA was extracted from tissue and microarrays completed, with test samples compared with standard human reference RNA. Subjects were characterised by performance measures of maximal oxygen uptake (VO2max) on a cycle ergometer and maximal concentric and eccentric leg strength on an isokinetic dynamometer. 263 genes were differentially expressed in trained (TR collectively ET + ST) subjects compared with Con (P<0.05) while 21 genes were different between ST and ET (P<0.05). Manual cluster analyses revealed significant regulation of genes involved in muscle structure and development in TR subjects compared with Con (P<0.05), and expression of these correlated significantly with measures of performance (P<0.05). ET had increased and ST decreased expression of gene clusters related to mitochondrial/oxidative capacity (P<0.05), and these mitochondrial gene clusters correlated significantly with VO2max (P<0.05). VO2max also correlated with expression of gene clusters that regulate fat and carbohydrate oxidation (P<0.05). We have demonstrated that chronic training has marked effects on basal gene expression by regulating levels of multiple mRNAs that transcribe genes for important functional groups in human skeletal muscle. Some specific gene clusters are expressed regardless of the training stimulus, whereas others exhibit divergent expression patterns as a result of specific training stimuli. Keywords: Comparative, cluster analysis, endurance training, strength training, muscle phenotype This was a crossectional study examining basal gene expression profiles of the human vastus lateralis. Twenty healthy males volunteered for this investigation. Seven were endurance trained cyclists (ET), who had been participating in endurance training for 8 yr. These subjects had no history of resistance training. Six subjects were strength trained power-lifters (ST) who had been participating exclusively in strength/resistance training for 9 yr. The final seven subjects were healthy controls (CON) that did not participate in any formal exercise. The study was approved by the Human Research Ethics Committee of RMIT University and Monash University Standing Committee on Ethics Research on Humans. After RNA extraction, amplification and indirect labelling, a dual colour micro-array analysis was conducted by hybridizing a test (muscle RNA; Cy5) sample and a reference (Universal human RNA; Cy3) sample on the AGRF glass slide human 8K micro-array. After data capture with the Genepix scanner and associated software data was normalised and the three populations compared using GeneSpring and simplified cluster analysis.
Project description:Retinal ganglion cells (RGCs) are the sole projection neurons that connect the eye with the brain, and the degeneration of these cells in diseases such as glaucoma results in vision loss or blindness. Similar to other neurons throughout the central nervous system, RGCs are postmitotic and therefore highly dependent upon autophagy to remove damaged proteins or organelles to maintain proper cellular homeostasis. Autophagy deficits have been implicated in multiple neurodegenerative diseases including glaucoma. In addition, a subpopulation of glaucoma patients possesses mutations in the autophagy receptor Optineurin (OPTN) resulting glaucoma within a normal range of intraocular pressure, with the OPTN(E50K) mutation known to induce a severe degeneration. Despite this, our knowledge of how autophagy impairment promotes neurodegeneration within RGCs remains limited. We advanced a human pluripotent stem cell (hPSC) model of RGC neurodegeneration with an underlying OPTN(E50K) mutation to study how autophagy disruption contributes to RGC neurodegeneration. We identified OPTN protein was reduced but accumulated within the somas in RGCs with the OPTN(E50K) mutation, and this accumulation was associated with a decrease in autophagic flux. To rule out the possibilities that the specificity of the antibody incapable to recognize E50K region resulting the reduction of OPTN protein, we performed proteomics analysis at week 2 hPSC-RGCs of post purification and identified 154 downregulated proteins as well as 178 upregulated proteins associated with OPTN(E50K) RGCs compared with isogenic controls. Taken together, we identified proteins that were altered by OPTN(E50K) mutation in RGCs, and which may provide potential mechanisms that contribute to RGC neurodegeneration.
Project description:This SuperSeries is composed of the following subset Series: GSE16733: Analysis of Gene Expression in Tissues of Two Turmeric Varieties at Different Developmental Stages GSE16734: Analysis of Gene Expression in Ginger Tissues at Different Developmental Stages Refer to individual Series
Project description:Rhizome, root and leaf of Yellow ginger were compared in this study. Rhizomes from 2, 3, 4, 6, and 7 month old plants (after planting) were compared to each other and to root from 2 and 7 month plants and leaves from 2 and 7 month old plants. Plants were grown under controlled conditions in the greenhouse. We used an interwoven loop design for hybridizations. There are two interwoven loops included in this experiment: one for rhizome developmental stages (2, 3, 4, 6, and 7 months old), the other one for all tissues of 2 and 7 month old plants. These interwoven designs are connected at the 2 month old and 7 month old rhizome samples.
Project description:Two varieties of turmeric, FMO (Fat Mild Orange) and TYA (Thin Yellow Aromatic) were compared. Rhizomes were harvested 3, 5, and 7 months after planting, roots were harvested at 7 months, and leaves were harvested at 7 months. Plants were grown under controlled conditions in the greenhouse. We used an interwoven loop design for hybridizations. There are two interwoven loops included in this experiment, one for rhizome samples from the different developmental stages, and a second for leaf and root 7 month old samples compared to 7 month old rhizome samples. The two loops were connected at the 7 month old rhizome samples.
Project description:Chickens were kept under a regimen of 12 hours of light and 12 hours of dark for 7 days. At LD2, 2 hours into the light cycle on the 8th day, 3 chickens were sacrificed by decapitation and their retinas dissected and pooled. Similarly, at LD18, 6 hours into the dark cycle on the 8th day, retinas were harvested from 3 chickens. Total RNA was extracted from each set of retinas using Trizol Reagent (Invitrogen). The total RNA samples were amplified to produce aRNA using the Message Amp Kit (Ambion). Randomly primed fluorescent probes were produced from the aRNA samples using a Genisphere 3DNA Array 900MPX expression array detection kit. The fluorescent dye on the probe derived from the experimental aRNA (LD2) was Cy5 while the dye on the control probe (LD18) was Cy3. Hybridizations and washes were as suggested by Genisphere. Labeled arrays were scanned in an Affymetrix 428 array scanner. The images obtained were subsequently analyzed by GenePixPro software (Axon Instruments). The GenePix results (.gpr) file was further analyzed by GeneSpring 5 (Silicon Genetics) which applied intensity dependent LOWESS normalization to the results and calculated normalized Cy5 to Cy3 ratios. This GEO Series was created by the GEO staff as part of a cleanup effort to ensure that all GEO Samples are included within a Series entry.