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Roubroeks, J. A. Y.

Publications and source records attributed to Roubroeks, J. A. Y..

3 recordsLinked to original sources

Prediction of Cell States and Key Transcription Factors of the Human Cornea through Integrated Single-Cell Omics Analyses

The cornea, a transparent tissue composed of multiple layers, allows light to enter the eye. Several single-cell RNA-seq analyses have been performed to explore the cell states and to understand the cellular composition of the human cornea. However, the inconsistences in cell state annotations between these studies complicate the application of these findings in corneal studies. To address this, we integrated single-cell RNA-seq data from four published studies and created a human corneal cell state meta-atlas. This meta-atlas was subsequently evaluated in two applications. First, we developed a machine learning pipeline cPredictor, using the human corneal cell state meta-atlas as input, to annotate corneal cell states. We demonstrated the accuracy of cPredictor and its ability to identify novel marker genes and rare cell states in the human cornea. Furthermore, cPredictor revealed the differences of the cell states between pluripotent stem cell-derived corneal organoids and the human cornea. Second, we integrated the single-cell RNA-seq based cell state meta-atlas with chromatin accessibility data, conducting motif-focused and gene regulatory network analyses. These approaches identified distinct transcription factors driving cell states of the human cornea. The novel marker genes and transcription factors were validated by immunohistochemistry. Overall, this study offers a reliable and accessible reference for profiling corneal cell states, which facilitates future research in cornea development, disease and regeneration. Significance statementThis study creates a human corneal cell state meta-atlas that provides a common nomenclature of cells in the human cornea, through integrating multiple single-cell RNA-seq analyses. Using this meta-atlas, we developed a machine learning pipeline, cPredictor, to accurately annotate cell states in corneal studies using single-cell RNA-seq. Additionally, we identified distinct transcription factors driving cell states through integrating the atlas with chromatin accessibility data. This meta-atlas and the computational tool cPredictor enable future research in cornea development, disease, and regeneration.

cell biology↗

Epigenome-wide profiling in the dorsal raphe nucleus highlights cell-type-specific changes in TNXB in Alzheimer's disease

Recent studies have demonstrated that the dorsal raphe nucleus (DRN) is among the first brain regions affected in Alzheimers disease. Hence, in this study we conducted the first comprehensive epigenetic analysis of the DRN in AD, targeting both bulk tissue and single isolated cells. The Illumina Infinium MethylationEPIC BeadChip array was used to analyze the bulk tissue, assessing differentially modified positions (DMoPs) and regions (DMoRs) associated with Braak stage. The strongest Braak stage-associated DMoR in TNXB was targeted in a second patient cohort utilizing single laser-capture microdissected serotonin-positive (5-HT+) and -negative (5-HT-) cells isolated from the DRN. Our study revealed previously identified epigenetic loci, including TNXB and PGLYRP1, and novel loci, including RBMXL2, CAST, GNAT1, MALAT1, and DNAJB13. Strikingly, we found that the methylation profile of TNXB depends both on disease phenotype and cell type analyzed, emphasizing the significance of single cell(-type) neuroepigenetic studies in AD.

neuroscience↗

Meta-analysis of epigenome-wide association studies in Alzheime's disease highlights 220 differentially methylated loci across cortex

Epigenome-wide association studies of Alzheimers disease have highlighted neuropathology-associated DNA methylation differences, although existing studies have been limited in sample size and utilized different brain regions. Here, we combine data from six DNA methylomic studies of Alzheimers disease (N=1,453 unique individuals) to identify differential methylation associated with Braak stage in different brain regions and across cortex. We identify 236 CpGs in the prefrontal cortex, 95 CpGs in the temporal gyrus and ten CpGs in the entorhinal cortex at Bonferroni significance, with none in the cerebellum. Our cross-cortex meta-analysis (N=1,408 donors) identifies 220 CpGs associated with neuropathology, annotated to 121 genes, of which 84 genes have not been previously reported at this significance threshold. We have replicated our findings using two further DNA methylomic datasets consisting of a further > 600 unique donors. The meta-analysis summary statistics are available in our online data resource (www.epigenomicslab.com/ad-meta-analysis/).

genomics↗