Project description:The retinal projection neurons, retinal ganglion cells (RGCs), can be categorized into distinct morphological and functional subtypes and by the laterality of their projections. Here, we used a new method for purifying the sparse population of ipsilaterally projecting RGCs in mouse retina from their contralaterally-projecting counterparts during embryonic development through rapid retrograde labeling followed by fluorescence-activated cell sorting (FACS). Through microarray analysis, we have uncovered the distinct molecular signatures that define and distinguish ipsilateral and contralateral RGCs during the critical period of axonal outgrowth and decussation, with over three hundred genes differentially experienced within these two cell populations. Amongst the genes upregulated in ipsilateral RGCs are many that are known to be expresed in progenitors cells and mark “immaturity," including Math5 (Atoh7), Sox2, and cyclin D2. Many of these differentially regulated genes were subsequently validated via in vivo expression analysis. Thus, the molecular signatures of ipsilateral and contralateral RGCs and the mechanisms that regulate their differentiation are more diverse than previously expected.
Project description:To obtain and analyze early retinal changes at molecular level at 24h after ipsilateral intraorbital nerve radiation injury by gamma knife surgery Unilateral intraorbital optic nerves of three Rhesus Macaques were treated by gamma knife surgery (GKS) with irradiated doses of 15Gy, while the contralateral optic nerves and retinas served as the control. Gene expression profiles of control and affected retinas were analyzed with Affymetrix Rhesus Macaque Genome arrays at 24h after treatment
Project description:Axon pathfinding is a key step during the formation of neural circuits but however the transcriptional mechanisms regulating its progression remain poorly understood. The binary decision of crossing or avoiding the midline that neurons make during developmente midline that mammalian retinal ganglion cell (RGC) axons take at the optic chiasm has classically represented a robust model to search for novel mechanisms controlling the selection of axonal trajectories. Here, in order to identify new axon pathfinding regulators, we compared the transcriptome and chromatin accessibility profiles of mammalian retinal ganglion cells RGCs projecting ipsilateral (iRGCs) or contralaterally (cRGCs). Overall, our analyses retrieved dozens of new molecules potentially involved in axon pathfinding and uncovered the regulatory logic behind axon trajectories selection.
Project description:Objective: To identify genes that are differentially expressed in retinal ganglion cells undergoing axon regeneration after optic nerve injury. Adult mice that express cyan-fluorescent protein (CFP) in RGCs were treated with pro-regenerative treatment after optic nerve injury. The treated RGCs were selected by FACS (CFP+mcherry) and their RNA profiles were analyzed.
Project description:Expression profiling of L4 and L5 Dorsal Root Ganglion (DRG) in the spinal nerve ligation model of neuropathic pain. The goal of the study was to identify genes involved in neuropathic pain This series of samples comprises of contralateral and ipsilateral L4 and L5 DRG tissue collected 4 weeks after rats underwent a L5 spinal nerve ligation (SNL) or a sham operation with no L5 spinal nerve ligation. This defines 8 groups (i) contralateral L4 DRG from the sham cohort (n=5), (ii) ipsilateral L4 DRG from sham cohort (n=5), (iii) contralateral L4 DRG from SNL cohort (n=5), (iv) ipsilateral L4 DRG from the SNL chort (n=5), (v) contralateral L5 DRG from the sham cohort (n=5), (vi) ipsilateral L5 DRG from sham cohort (n=5), (vii) contralateral L5 DRG from SNL cohort (n=5), (viii) ipsilateral L5 DRG from the SNL cohort (n=5)
Project description:Dnmt3a deficiency in retinal ganglion cells promotes axon regeneration in an optic nerve crush mouse model. To investigate the role of Dnmt3a in axon regeneration, retinal ganglion cell nuclei were sorted from control and retinal ganglion cell-specific Dnmt3a knockout mice at 2 days post optic nerve crush and applied for single nuclei RNA-seq analysis by 10X Genomics technology.
Project description:Dnmt3a deficiency in retinal ganglion cells promotes axon regeneration in an optic nerve crush mouse model. To investigate the role of Dnmt3a in axon regeneration, retinal ganglion cells isolated from control and retinal ganglion cell-specific Dnmt3a knockout mice at 2 days post-crush were applied for Bulk RNA-seq analysis by NovaSeq platform.
Project description:Dnmt3a deficiency in retinal ganglion cells promotes axon regeneration in an optic nerve crush mouse model. To investigate the contribution of Dnmt3a to DNA methylation and axon regeneration, retinal ganglion cells isolated from control and retinal ganglion cell-specific Dnmt3a knockout mice at 2 days post-crush were applied for whole genome bisulfite-seq analysis by Illumina NovaSeq 6000.
Project description:Retinal ganglion cell (RGC) death is the final consequence of many blinding diseases, where there is considerable variation in the time course and severity of RGC loss. Indeed, this process appears to be influenced by a wide variety of genetic and environmental factors. In this study we explored the genetic basis for differences in ganglion cell death in two inbred strains of mice. We found that RGCs are more susceptible to death following optic nerve crush in C57BL/6J mice (54% survival) than in DBA2/J mice (62% survival). Using the Illumina Mouse-6 microarray, we identified 1,580 genes with significant change in expression following optic nerve crush in these two strains of mice. Our analysis of the changes occurring after optic nerve crush demonstrated that the greatest amount of change (44% of the variance) was due to the injury itself. This included changes associated with ganglion cell death, reactive gliosis, and abortive regeneration. The second pattern of gene changes (23% of the variance) was primarily related to differences in gene expressions observed between the C57BL/6J and DBA/2J mouse strains. The remaining changes in gene expression represent interactions between the effects of optic nerve crush and the genetic background of the mouse. We extracted one genetic network from this dataset that appears to be related to tissue remodeling. One of the most intriguing sets of changes included members of the crystallin family of genes, which may represent a signature of pathways modulating the susceptibility of cells to death. Differential responses to optic nerve crush between two widely used strains of mice were used to define molecular networks associated with ganglion cell death and reactive gliosis. These results form the basis for our continuing interest in the modifiers of retinal injury. 18 Samples: 9 per strain (C57BL/6J & DBA/2J); 3 conditions per strain
Project description:To investigate the role of aldose reductase (AR) inhibition using Sorbinil on retinal microglia (RMG) activation, retinal ganglion cell (RGC) survival, and axon regeneration after optic nerve trauma. We observed that AR inhibition using Sorbinil attenuates RMG activation and subsequently promotes RGC survival and delays axon degeneration one week after optic nerve crush.
