Project description:The autosomal-dominant Y2334N mutation in PRPF8 is associated with retinitis pigmentosa, a progressive retinal disorder. Here, we investigated how the Y2334N mutation affects circRNA differential expression in the retinas of homozygous Y2334N mutant mice.
Project description:Mutations in pre-mRNA processing factors (PRPFs) cause autosomal dominant retinitis pigmentosa (RP), but it is unclear why mutations in ubiquitously expressed genes cause retinal disease. We have generated transcriptome profiles from RP11 (PRPF31-mutated) patient-derived retinal organoids and retinal pigment epithelium (RPE), as well as Prpf31+/- mouse tissues, which revealed that disrupted alternative splicing occurred for specific splicing programmes. Mis-splicing of genes encoding pre-mRNA splicing proteins was limited to patient-specific retinal cells and Prpf31+/- mouse retinae and RPE. Mis-splicing of genes implicated in ciliogenesis and cellular adhesion was associated with severe RPE defects that include disrupted apical-basal polarity, reduced trans-epithelial resistance and phagocytic capacity, and decreased cilia length and incidence. Disrupted cilia morphology also occurred in patient-derived photoreceptors, associated with progressive degeneration and cellular stress. In situ gene-editing of a pathogenic mutation rescued protein expression and key cellular phenotypes in RPE and photoreceptors, providing proof-of-concept for future therapeutic strategies.
Project description:Mutations in the carboxy terminal of the core spliceosome factor PRPF8 cause autosomal dominant retinitis pigmentosa (RP) 13. Comprehensive cellular, biochemical, and molecular investigations of iPSC-derived retinal organoids, retinal pigment epithelium (RPE) and kidney organoids from four patients carrying the pathogenic PRPF8 RP type 13 c.6926A>C (p.H2309P) heterozygous missense mutation, revealed retinal tissue-specific effects including lower splicing specificity, ciliary abnormalities, altered apical-basal polarity, rod degeneration and loss of photoreceptors. The p.H2309P mutation affected the 5’ splice site recognition by PRPF8 of transcripts encoding ciliary proteins, altered spliceosome kinetics and organisation of nuclear speckles as well as PRPF8 binding to spliceosomal U6 snRNAs and snoRNAs, leading to accumulation of unspliced poly A+ mRNAs specifically in RPE cells and retinal organoids. Together these data provide the most comprehensive characterisation of splicing factor causing RP disease, providing molecular insights into the tissue specificity of pathomechanisms and informing future therapeutic approaches.
Project description:Rhodopsin P23H mutation is the most comment mutation causing autosomal dominant retinitis pigmentosa in the USA. The goal of this project is to compare the transcriptome changes of the Rhodopsin P23H knock-in mouse model of adRP to the wildtype control at different ages. The transcriptomic profile will help us understand the molecular events along the pathophysiology of reititis pigmentosa in this mouse model. We include the RNA seq data of Rhodopsin P23H heterozygous mouse retinas at 1, 3 and 6 months of age to compare with age-matched wildtype mouse retinas. N=3 and each sample is from an individual animal.
Project description:Pathogenic variants in splicing factors are the second most common cause of autosomal dominant retinitis pigmentosa (RP), with mutations in PRPF31 being the most prevalent. Here, we characterize a novel intronic variant in PRPF31 (c.1074-11C>G) that creates a cryptic 3′ splice site, resulting in an aberrantly spliced transcript predicted to encode a protein with an altered C-terminus. However, the pathogenic protein was not detected in patient-derived induced pluripotent stem cells (iPSCs). In addition, expression of PRPF31 protein was reduced in patient iPSC-derived retinal pigment epithelium (RPE). To correct the splicing defect, we designed a panel of antisense oligonucleotides (ASOs) targeting putative RNA-binding sites in exon 10 and intron 10 and identified a candidate that corrects PRPF31 splicing in a minigene reporter system as well as in patient-derived iPSCs and RPE. Finally, we showed that ASO treatment enhances PRPF31 protein expression in patient iPSC-derived RPE, supporting its potential as a therapeutic approach to restore PRPF31 expression in RP patients.
Project description:Recessive retinitis pigmentosa (RP) is often caused by nonsense mutations that lead to low mRNA levels as a result of nonsense-mediated decay. Some RP genes are expressed at detectable levels in leukocytes as well as in the retina. We designed a microarray-based method to find recessive RP genes based on low lymphoblast mRNA expression levels Keywords: Recessive mutations; mRNA expression; nonsense mediated-decay; retinitis pigmentosa; lymphocyte; Affymetrix genechip Human Genome U133Plus2.0.
Project description:Inherited retinal degenerations (IRDs) are a leading cause of blindness among the young population in the developed world. Approximately half of IRDs initially manifest as gradual loss of night vision and visual fields, characteristic of retinitis pigmentosa (RP). Due to challenges in genetic testing, and the large heterogeneity of mutations underlying RP, targeted gene therapies are an impractical largescale solution in the foreseeable future. For this reason, identifying common key pathophysiological pathways in IRDs that could be used as targets for mutation-agnostic and disease-modifying therapies (DMTs) is warranted. In this study, we investigated retinal proteome of three distinct IRD mouse models, comparing to sex- and age-matched wild-type mice. Specifically, we used the Pde6βRd10 (rd10) and RhoP23H/WT (P23H) mouse models of autosomal recessive and autosomal dominant RP, respectively, as well as the Rpe65-/- mouse model of Leber´s congenital amaurosis type 2 (LCA2). The mice were housed at two distinct institutions and analyzed using LC-MS in three separate facilities/instruments following data-dependent and data-independent acquisition modes. This cross-institutional and multi-methodological approach signifies the reliability and reproducibility of the results. The largescale retinal proteome profiling, coupled with in vivo electroretinography recordings, provided us with a reliable basis for comparing the disease phenotypes and severity.