Biology subjects

Van Heetvelde, M.

Publications and source records attributed to Van Heetvelde, M..

3 recordsLinked to original sources

bioRxiv2023

Juggling offsets unlocks RNA-seq tools for fast scalable differential usage, aberrant splicing and expression analyses.

RNA-seq data analysis relies on many different tools, each tailored to specific applications and coming with unique assumptions and limitations. Indeed, tools for differential transcript usage or rare disease diagnosis through splicing and expression outliers, either lack performance, discard information, or do not scale to large datasets. We show that replacing normalization offsets unlocks bulk RNA-seq tools for differential usage and aberrant splicing, providing a single framework for various short- and long-read applications. We then introduce saseR, a tool for prioritizing expression and usage outliers that is much faster than state-of-the-art methods, and significantly outperforms these for aberrant splicing detection.

bioinformatics↗

bioRxiv2022

Multi-omics profiling, in vitro and in vivo enhancer assays dissect the cis -regulatory mechanisms underlying North Carolina macular dystrophy, a retinal enhanceropathy

North Carolina macular dystrophy (NCMD) is a rare autosomal dominant disease affecting macular development. The disease is caused by non-coding single nucleotide variants (SNVs) in two hotspot regions near PRDM13 and by duplications in two distinct chromosomal loci, overlapping DNase I hypersensitive sites near either PRDM13 or IRX1. To unravel the mechanisms by which these variants cause disease, we first established a genome-wide multi-omics retinal database, RegRet. Integration of UMI-4C profiles we generated on adult human retina then allowed fine-mapping of the interactions of the PRDM13 and IRX1 gene promoters, and the identification of eighteen candidate cis-regulatory elements (cCREs), the activity of which was investigated by luciferase and Xenopus enhancer assays. Next, luciferase assays showed that the non-coding SNVs located in the two hotspot regions of PRDM13 affect cCRE activity, including two novel NCMD-associated non-coding SNVs that we identified. Interestingly, the cCRE containing one of these SNVs was shown to interact with the PRDM13 promoter, demonstrated in vivo activity in Xenopus, and is active at the developmental stage when progenitor cells of the central retina exit mitosis, putting forward this region as a PRDM13 enhancer. Finally, mining of single-cell transcriptional data of embryonic and adult retina revealed the highest expression of PRDM13 and IRX1 when amacrine cells start to synapse with retinal ganglion cells, supporting the hypothesis that altered PRDM13 or IRX1 expression impairs interactions between these cells during retinogenesis. Overall, this study gained insight into the cis-regulatory mechanisms of NCMD and supports that this condition is a retinal enhanceropathy. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=149 SRC="FIGDIR/small/481329v2_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@4a85e3org.highwire.dtl.DTLVardef@9bfe55org.highwire.dtl.DTLVardef@156a9d8org.highwire.dtl.DTLVardef@a8cb92_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

bioRxiv2021

Loss of CEP162 function at the primary cilium delays ciliogenesis and causes retinal ciliopathy in humans

Defects in primary or motile cilia result in a variety of human pathologies, and retinal degeneration is frequently associated with these so-called ciliopathies. We show that homozygosity for a truncating variant in CEP162, a centrosome and microtubule-associated protein required for transition zone (TZ) assembly during ciliogenesis and neuronal differentiation in the retina, causes late-onset retinitis pigmentosa in 2 unrelated families. The mutant CEP162-E646R*5 protein is expressed and properly localized to the mitotic spindle but missing from the basal body in primary and photoreceptor cilia. This impairs recruitment of TZ components to the basal body and corresponds to complete loss of CEP162 function at the ciliary compartment, reflected by delayed formation of dysmorphic cilia. In contrast, rescue of increased cell death in the developing mouse retina after shRNA knockdown of Cep162 by expression of CEP162-E646R*5 indicates that the mutant retains its role for retinal neurogenesis. Human retinal degeneration thus results from specific loss of ciliary CEP162 function. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=134 HEIGHT=200 SRC="FIGDIR/small/469779v3_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@593dccorg.highwire.dtl.DTLVardef@e84d7forg.highwire.dtl.DTLVardef@137ce56org.highwire.dtl.DTLVardef@cba1f7_HPS_FORMAT_FIGEXP M_FIG C_FIG

genetics↗