Project description:In mammalian albinism, disrupted melanogenesis in the retinal pigment epithelium (RPE) is associated with fewer retinal ganglion cells (RGCs) projecting ipsilaterally to the brain, resulting in numerous abnormalities in the retina and visual pathway, especially binocular vision. To further understand the molecular link between disrupted RPE and a reduced ipsilateral RGC projection in albinism, we compared gene expression in the embryonic albino and pigmented mouse RPE.
Project description:The retinal pigment epithelium (RPE) is a monolayer of polarized epithelial cells lying between the retina and the choroid/sclera, with a major function in supporting photoreceptor homeostasis, but the role of RPE in eye size regulation is yet to be further explored. it was recently reported that selective deletion of Low density lipoprotein receptor-related protein 2 (Lrp2) in the mouse RPE resulted in large eyes, similar to the phenotypes of Lrp2 whole eye knockout mice, suggesting that the RPE is the tissue in which LRP2 functions. Here, to investigate which downstream pathways of Srebp2 and Lrp2 are responsible for regulating eye growth, we performed RNA-seq analysis with the mouse RPE tissues. Postnatal day 0 (P0) mice were injected with AAV8-Best1-GFP/nSrebp2/ctrl sh/Lrp2 sh1/Lrp2 sh2 viruses to overexpress the constitutively active form of Srebp2 or to knockdown Lrp2 in the RPE specifically. At P14, RPE cells were carefully dissociated for RNA extraction. Via RNA-seq analysis and functional validation, we identified that Bmp2 is the target and the effector of the Srebp2-Lrp2 pathway. Overall, the present study unveils an essential role of RPE in regulating eye size via the Srebp2-Lrp2-Bmp2 signaling pathway, shedding light on the underlying mechanism of eye size control.
Project description:To evaluate the effect of oxidative stress on transcript localization in the retinal pigment epithelium (RPE), we performed poly-A RNA sequencing on nuclear and cytoplasmic fractions from induced pluripotent stem cell-derived retinal pigment epithelium (iPSC-RPE) cells exposed to hydrogen peroxide, as well as untreated controls.
Project description:The retinal pigment epithelium (RPE) provides vital support to photoreceptor cells and its dysfunction is associated with the onset and progression of age-related macular degeneration (AMD). Surgical provision of RPE cells may ameliorate AMD and thus it would be valuable to develop sources of patient-matched RPE cells for this application of regenerative medicine. We describe here the generation of functional RPE-like cells from fibroblasts that represent an important step toward that goal. We identified candidate master transcriptional regulators of RPEs using a novel computational method and then used these regulators to guide exploration of the transcriptional regulatory circuitry of RPE cells and to reprogram human fibroblasts into RPE-like cells. The RPE-like cells share key features with RPEs derived from healthy individuals, including morphology, gene expression and function, and thus represent a step toward the goal of generating patient-matched RPE cells for treatment of macular degeneration. Expression analysis was performed on induced retinal pigment epithelium-like cells.
Project description:Illumina Infinium HumanMethylation450 BeadChip data from genomic DNA of retinal pigment epithelium from Age-related Macular Degeneration patients or age-matched controls.
Project description:Eye development and photoreceptor maintenance requires the retinal pigment epithelium (RPE), a thin layer of cells that underlies the neural retina. Despite its importance, RPE development has not been studied by a genomic approach. A microarray expression profiling methodology was established in this study for studying RPE development. The intact retina with RPE attached was dissected from developing embryos, and differentially expressed genes in RPE were inferred by comparing the dissected tissues with retinas without RPE using microarray and statistical analyses. We found 8810 probesets to be significantly expressed in RPE at 52 hours post-fertilization (hpf), of which 1443 might have biologically meaningful expression levels. Further, 78 and 988 probesets were found to be significantly over- or under-expressed in RPE respectively compared to retina. Also, 79.2% (38/48) of the known over-expressed probesets have been independently validated as RPE-related transcripts. The results strongly suggest that this methodology can obtain in vivo RPE specific gene expression from the zebrafish embryos and identify novel RPE markers. Keywords: Development, retina, retinal pigment epithelium