Project description:Retinitis pigmentosa (RP) and Leber congenital amaurosis are inherited retinal dystrophies caused by mutations in, among others, the Crumbs homologue 1 (CRB1) gene. CRB1 is required for organizing apical-basal polarity and adhesion between photoreceptors and Müller glial cells. Using human CRB1 patient induced pluripotent stem cells from RP patients we derived CRB1 retinal organoids, with diminished expression of variant CRB1 protein with immunohistochemical analysis. Single cell RNA-sequencing revealed impact on, among others, the endosomal pathway and cell adhesion and migration in CRB1 patient derived retinal organoids compared to isogenic controls. Adeno-associated viral (AAV) vector-mediated hCRB2 or hCRB1 gene augmentation in Müller glial and photoreceptor cells partially restored the histological and differentially expressed genes phenotype. Altogether, we show proof-of-concept that AAV.hCRB1 or AAV.hCRB2 treatment improved the phenotype of CRB1 patient derived retinal organoids, providing essential information for future gene therapy approaches for patients with mutations in the CRB1 gene.
Project description:Retinitis Pigmentosa (RP) is a progressive retinal degeneration in which the retina loses nearly all of its photoreceptor cells and undergoes major structural changes. Little is known regarding the role the resident glia, the Müller glia, play in the progression of the disease. Here we define gene expression changes in Müller glial cells (MGCs) from two different mouse models of RP, the retinal degeneration 1 (rd1) and rhodopsin knock-out (Rhod-ko) models. The RNA repertoire of 28 single MGCs was comprehensively profiled, and a comparison was made between MGC from wild type (WT) and mutant retinas. Two time points were chosen for analysis, one at the peak of rod photoreceptor death and one during the period of cone photoreceptor death. MGCs have been shown to respond to retinal degeneration by undergoing gliosis, a process marked by the upregulation of GFAP. In this data, many additional transcripts were found to change. These can be placed into functional clusters, such as retinal remodeling, stress response, and immune related response. It is noteworthy that a high degree of heterogeneity among the individual cells was observed, possibly due to their different spatial proximities to dying cells, and/or inherent heterogeneity among MGCs.
Project description:Retinitis pigmentosa (RP) is an inherited eye disease that causes progressive vision loss.To investigate the biological processes and molecular changes that occur in different cell types in the retinas in rd1 mice, a mouse model of retinitis pigmentosa, we performed single-cell RNA-seq to examine the transcriptomes of various retinal cells.
Project description:Transcriptome perturbations within NIH3T3 cell lines expressing rhodopsin and its retinitis pigmentosa mutant and implication for drug screening
Project description:In mammals, retinal damage is followed by Müller glia cell activation and proliferation. While retinal gliosis persists in adult mammals after an insult or disease, some vertebrates, including zebrafish, have the capacity to regenerate. We believe we are the first group to show that gliosis is a fibrotic-like process in mammals’ eyes caused by differential activation of canonical and non-canonical TGFβ signaling pathways.
2019-11-03 | GSE132140 | GEO
Project description:Muller glial responses compensate for degenerating photoreceptors in retinitis pigmentosa
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
| S-EPMC8784167 | biostudies-literature
Project description:FGF21 via retinal glial modeling preserves photoreceptor function in retinitis pigmentosa