Purpose: Age-related degeneration (AMD) is a major cause of blindness in developed countries. The molecular pathogenesis of early events in AMD is poorly understood. We investigated differential gene expression in samples of human retinal pigment epithelium (RPE)/choroid from early AMD and control maculas using exon-based arrays. Methods: Gene expression levels in nine early AMD and nine control human donor eyes were assessed using Affymetrix Human Exon ST 1.0 arrays. Two controls did not pass quality control and were removed. Differentially expressed genes were annotated using DAVID, and gene set enrichment analysis (GSEA) was performed on RPE-specific and endothelium-associated gene sets. CFH genotype was also assessed and differential expression was analyzed with respect to high AMD risk (YH/HH) and low AMD risk (YY) genotypes. Results: Seventy-five genes were identified as differentially expressed (raw p-value < 0.01; >50% fold change, mean log2 expression level in AMD or control median of all average gene expression values); however, no genes were significant (adj. p-value < 0.01) after correction for multiple hypothesis testing. Of 52 genes with decreased expression in AMD (fold change < 0.5; raw p-value < 0.01), 18 genes were identified by DAVID analysis as associated with vision or neurological processes. GSEA of RPE-associated and endothelium-associated genes revealed a significant decrease in genes typically expressed by endothelial cells in the early AMD group compared to controls, consistent with previous histologic and proteomic studies. Analysis with respect to CFH genotype indicated decreased expression of ADAMTS9 in eyes with high-risk genotypes (fold change = -2.61; raw p-value = 0.0008). Conclusions: GSEA results suggest that RPE transcripts are preserved or elevated in early AMD, concomitant with loss of endothelial cell marker expression. These results are consistent with the notion that choroidal endothelial cell dropout occurs early in the pathogenesis of AMD.
Altered gene expression in dry age-related macular degeneration suggests early loss of choroidal endothelial cells.
Sex, Age, Specimen part
View SamplesPurpose: Single-cell RNA sequencing has revolutionized cell-type specific gene expression analysis. The goals of this study are to compare cell specific gene expression patterns between retinal cell types originating from the fovea and the periphery of human eyes. Methods: Independent libraries were prepared for foveal and peripheral samples of neural retina from three donors using the 10x Chromium system. Libraries were sequenced on a HiSeq4000. Sequenced reads were mapped to the human genome build hg19 will CellRanger(v3.0.1) and filters removed cells likely to be doublets or cells with a high proportion of mitochondrial reads. Clustering of cells with similar expression profiles was performed with Seurat (v2.3.4). Results: Independent libraries were prepared for foveal and peripheral samples of neural retina from three donors using the 10x Chromium system. Libraries were sequenced on a HiSeq4000. Sequenced reads were mapped to the human genome build hg19 will CellRanger(v3.0.1) and filters removed cells likely to be doublets or cells with a high proportion of mitochondrial reads. Clustering of cells with similar expression profiles was performed with Seurat (v2.3.4). Conclusions: Our study generates a large atlas of human retinal transcriptomes at the single cell level. We identified the majority of expected neural and supportive cell types, and describe regional differences in gene expression between the fovea and the periphery. Our results show that that single-cell RNA sequencing can be performed on human retina after cryopreservation, and that cone photoreceptors and Muller cells demonstrate region-specific patterns of gene expression. Overall design: mRNA profiles for thousands of cells from foveal and peripheral retinal isolates were generated from three human donor eyes using 10X Genomics Chromium single-cell system followed by sequencing on an Illumina HiSeq 4000.
Molecular characterization of foveal versus peripheral human retina by single-cell RNA sequencing.
Subject
View SamplesWe used expression quantitative trait locus mapping in the laboratory rat (Rattus norvegicus) to gain a broad perspective of gene regulation in the mammalian eye and to identify genetic variation relevant to human eye disease. Of >31,000 gene probes represented on an Affymetrix expression microarray, 18,976 exhibited sufficient signal for reliable analysis and at least 2-fold variation in expression among 120 F2 rats generated from an SR/JrHsd x SHRSP intercross. Genome-wide linkage analysis with 399 genetic markers revealed significant linkage with at least one marker for 1,300 probes (alpha = 0.001; estimated empirical false discovery rate = 2%). Both contiguous and noncontiguous loci were found to be important in regulating mammalian eye gene expression. We investigated one locus of each type in greater detail and identified putative transcription-altering variations in both cases. We found an inserted cREL binding sequence in the 5' flanking sequence of the Abca4 gene associated with an increased expression level of that gene, and we found a mutation of the gene encoding thyroid hormone receptor beta 2 associated with a decreased expression level of the gene encoding short-wave sensitive opsin (Opn1sw). In addition to these positional studies, we performed a pairwise analysis of gene expression to identify genes that are regulated in a coordinated manner and used this approach to validate two previously undescribed genes involved in the human disease Bardet-Biedl syndrome. These data and analytic approaches can be used to facilitate the discovery of additional genes and regulatory elements involved in human eye disease.
Regulation of gene expression in the mammalian eye and its relevance to eye disease.
No sample metadata fields
View Samples3 pairs of wt and ClC-6 knockout mice, RNA from p14 hippocampus
Lysosomal storage disease upon disruption of the neuronal chloride transport protein ClC-6.
Sex, Age, Specimen part, Subject, Time
View SamplesmRNA sequencing was used to identify genome wide transcriptional changes occuring in fly heads in response to spermidine feeding. This study shed light on the molecular mechanisms through wich spermidine can protect against age-dependent memory impairment. Overall design: mRNA profiles from 3 and 10 day old Drosophila melanogaster heads were generated in duplicate by deep sequencing using Illumina GAIIx. mRNA profiles from flies that were fed food with 5mM spermidine were compared to profiles from flies that had no spermidine in thier food.
Restoring polyamines protects from age-induced memory impairment in an autophagy-dependent manner.
Age, Specimen part, Subject
View SamplesThe normal gene expression profiles of the tissues in the eye are a valuable resource for considering genes likely to be involved with disease processes. This is based on the assumption that transcript abundances in healthy tissue are correlated to the continued health of that tissue.
Exon-level expression profiling of ocular tissues.
Specimen part
View SamplesMaintenance and maturation of primordial germ cells is controlled by complex genetic and epigenetic cascades, and disturbances in this network lead to either infertility or malignant aberration. Transcription factor Tcfap2c / TFAP2C has been described to be essential for primordial germ cell maintenance and to be upregulated in several human germ cell cancers. Using global gene expression profiling, we identified genes deregulated upon loss of Tcfap2c in primordial germ cell-like cells. We show that loss of Tcfap2c affects many aspects of the genetic network regulating germ cell biology, such as downregulation maturation markers and induction of markers indicative of somatic differentiation, cell cycle, epigenetic remodeling, and pluripotency associated genes. Chromatin-immunoprecipitation analyses demonstrated binding of Tcfap2c to regulatory regions of deregulated genes (Sfrp1, Dmrt1, Nanos3, c-Kit, Cdk6, Cdkn1a, Fgf4, Klf4, Dnmt3b and Dnmt3l) suggesting that these genes are direct transcriptional targets of Tcfap2c in primordial germ cells. Since Tcfap2c deficient primordial germ cell like cells display cancer related deregulations in epigenetic remodeling, cell cycle and pluripotency control, the Tcfap2c-knockout allele was bred onto 129S2/Sv genetic background. There, mice heterozygous for Tcfap2c develop germ cell cancer with high incidence. Precursor lesions can be observed as early as E16.5 in developing testes displaying persisting expression of pluripotency markers. We further demonstrate, that mice with a heterozygous deletion of the Tcfap2c target gene Nanos3 are also prone to develop teratoma. These data highlight Tcfap2c as a critical and dose-sensitive regulator of germ cell fate.
Transcription factor TFAP2C regulates major programs required for murine fetal germ cell maintenance and haploinsufficiency predisposes to teratomas in male mice.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage.
Treatment
View SamplesGenome maintenance defects cause complex disease phenotypes characterized by developmental failure, cancer susceptibility and premature aging. It remains poorly understood how DNA damage responses function during organismal development and maintain tissue functionality when DNA damage accumulates with aging. Here we show that the FoxO transcription factor DAF-16 is activated in response to DNA damage during development while the DNA damage responsiveness of DAF-16 declines with aging. We find that in contrast to its established role in mediating starvation arrest, DAF-16 alleviates DNA damage induced developmental arrest and even in the absence of DNA repair promotes developmental growth and enhances somatic tissue functionality. We demonstrate that the GATA transcription factor EGL-27 co-regulates DAF-16 target genes in response to DNA damage and together with DAF-16 promotes developmental growth. We propose that EGL-27/GATA activity specifies DAF-16 mediated DNA damage responses to enable developmental progression and to prolong tissue functioning when DNA damage persists.
DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage.
Treatment
View SamplesGenome maintenance defects cause complex disease phenotypes characterized by developmental failure, cancer susceptibility and premature aging. It remains poorly understood how DNA damage responses function during organismal development and maintain tissue functionality when DNA damage accumulates with aging. Here we show that the FoxO transcription factor DAF-16 is activated in response to DNA damage during development while the DNA damage responsiveness of DAF-16 declines with aging. We find that in contrast to its established role in mediating starvation arrest, DAF-16 alleviates DNA damage induced developmental arrest and even in the absence of DNA repair promotes developmental growth and enhances somatic tissue functionality. We demonstrate that the GATA transcription factor EGL-27 co-regulates DAF-16 target genes in response to DNA damage and together with DAF-16 promotes developmental growth. We propose that EGL-27/GATA activity specifies DAF-16 mediated DNA damage responses to enable developmental progression and to prolong tissue functioning when DNA damage persists.
DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage.
Treatment
View Samples