Biology subjects

Perenthaler, E.

Publications and source records attributed to Perenthaler, E..

8 recordsLinked to original sources

bioRxiv2025

Empowering multiplexed ultra-throughout ribosome profiling with RiboWich

Ribosome profiling (RiboSeq) improved the understanding of mRNA translation, enabling the precise mapping of ribosome positioning along transcripts at single-nucleotide resolution. Although various library preparation protocols overcome the need for high input material, their technical complexity and limited efficiency hinder robust profiling, preventing them from keeping pace with other sequencing techniques and applications. To move towards high-throughput and single-cell RiboSeq technologies, we developed RiboWich (Ribosome sandWich). By directly ligating adaptors to ribosome-embedded RNA fragments, RiboWich eliminates the need for ribosome purification and size-selecting ribosome footprints and tackles two major bottlenecks, expanding RiboSeq for more advanced technologies. RiboWich offers robustness in profiling and excels in detecting upstream translons in immortalized and primary cells alike. By exploiting a dual-step multiplexing strategy, RiboWich enables the simultaneous profiling of at least 96 samples while retaining sensitivity and capturing condition-specific differences in translation. By enabling scalable, low-input translatome profiling, this advancement empowers proteogenomic approaches and AI/ML-driven data analysis to uncover regulatory dynamics, neoantigens, functional small translons, and drug-responsive signatures across diverse biological contexts and users. Altogether, RiboWich represents a straightforward, versatile, and scalable ribosome profiling conceptual platform that combines accessibility, sensitivity, and throughput potential, laying the foundation for advanced single-cell RiboSeq applications.

molecular biology↗

bioRxiv2025

Translation-specific disruption of Col1a1 expression in multiple models of Spinal Muscular Atrophy can be rescued by Risdiplam.

Spinal muscular atrophy (SMA) is a monogenic neurodegenerative disorder caused by decreased levels of Survival of Motor Neuron (SMN) protein. If left untreated, SMA patients have a poor prognosis, marked by the degeneration of motor neurons, progressive muscle weakness and atrophy. The approval of SMN-restoring therapies that improve symptoms and lifespan in patients with SMA has created emerging, non-neuronal phenotypes and an urgent need for deepening our understanding of disease pathogenesis. Leveraging the knowledge that SMN loss drives alterations in translation, we used multiple tissues from a mouse model of SMA to uncover early translational alterations in key mRNAs and proteins, which act as contributors to pathogenesis and hallmarks of the disease. Among hundreds of differentially translated mRNAs, Col1a1 emerged as a translation-specific manifestation of early defects in the mouse model. These findings were confirmed in fibroblasts derived from patients with varying levels of disease severity. Notably, treatment with SMN-restoring therapies rescued COL1A1 protein levels, particularly in fibroblasts from patients with the most severe forms of the disease. Overall, our study identifies COL1A1 as an indicator of disease severity in SMA, which captures early molecular alterations and respond to SMN-modifying therapies.

molecular biology↗

bioRxiv2024

Patient-specific responses to SMN2 splice-modifying treatments in spinal muscular atrophy fibroblasts

The availability of three therapies for the neuromuscular disease spinal muscular atrophy (SMA) highlights the need to match patients to the optimal treatment. Two of these treatments (nusinersen and risdiplam) target splicing of SMN2, but treatment outcomes vary from patient to patient. An incomplete understanding of the complex interactions between SMA genetics, SMN protein and mRNA levels, and gene-targeting treatments, limits our ability to explain this variability and identify optimal treatment strategies for individual patients. To address this, we analyzed responses to nusinersen and risdiplam in 45 primary fibroblast cell lines. Pre-treatment SMN2-FL, SMN2{Delta}7 mRNA, and SMN protein levels were influenced by SMN2 copy number, age, and sex. After treatment, SMN and mRNA levels were more heterogeneous. In 43% of patients, response to both therapies was similar, but in 57% one treatment led to a significantly higher SMN increase than the other treatment. Younger age, higher SMN2 copy number, and higher SMN levels before treatment predicted better in vitro efficacy. These findings showcase patient-derived fibroblasts as a tool for identifying molecular predictors for personalized treatment.

molecular biology↗

bioRxiv2021

Comprehensive multi-omics integration identifies differentially active enhancers during human brain development with clinical relevance

BackgroundNon-coding regulatory elements (NCREs), such as enhancers, play a crucial role in gene regulation and genetic aberrations in NCREs can lead to human disease, including brain disorders. The human brain is complex and can be affected by numerous disorders; many of these are caused by genetic changes, but a multitude remain currently unexplained. Understanding NCREs acting during brain development has the potential to shed light on previously unrecognised genetic causes of human brain disease. Despite immense community-wide efforts to understand the role of the non-coding genome and NCREs, annotating functional NCREs remains challenging. ResultsHere we performed an integrative computational analysis of virtually all currently available epigenome data sets related to human fetal brain. Our in-depth analysis unravels 39,709 differentially active enhancers (DAEs) that show dynamic epigenomic rearrangement during early stages of human brain development, indicating likely biological function. Many of these DAEs are linked to clinically relevant genes, and functional validation of selected DAEs in cell models and zebrafish confirms their role in gene regulation. Compared to enhancers without dynamic epigenomic rearrangement, these regions are subjected to higher sequence constraints in humans, have distinct sequence characteristics and are bound by a distinct transcription factor landscape. DAEs are enriched for GWAS loci for brain related traits and for genetic variation found in individuals with neurodevelopmental disorders, including autism. ConclusionOur compendium of high-confidence enhancers will assist in deciphering the mechanism behind developmental genetics of the human brain and will be relevant to uncover missing heritability in human genetic brain disorders.

genomics↗

bioRxiv2019

Loss of UGP2 in brain leads to a severe epileptic encephalopathy, emphasizing that bi-allelic isoform specific start-loss mutations of essential genes can cause genetic diseases

Developmental and/or epileptic encephalopathies (DEEs) are a group of devastating genetic disorders, resulting in early onset, therapy resistant seizures and developmental delay. Here we report on 12 individuals from 10 families presenting with a severe form of intractable epilepsy, severe developmental delay, progressive microcephaly and visual disturbance. Whole exome sequencing identified a recurrent, homozygous variant (chr2:64083454A>G) in the essential UDP-glucose pyrophosphorylase (UGP2) gene in all probands. This rare variant results in a tolerable Met12Val missense change of the longer UGP2 protein isoform but causes a disruption of the start codon of the shorter isoform. We show that the absence of the shorter isoform leads to a reduction of functional UGP2 enzyme in brain cell types, leading to altered glycogen metabolism, upregulated unfolded protein response and premature neuronal differentiation, as modelled during pluripotent stem cell differentiation in vitro. In contrast, the complete lack of all UGP2 isoforms leads to differentiation defects in multiple lineages in human cells. Reduced expression of Ugp2a/Ugp2b in vivo in zebrafish mimics visual disturbance and mutant animals show a behavioral phenotype. Our study identifies a recurrent start codon mutation in UGP2 as a cause of a novel autosomal recessive DEE. Importantly, it also shows that isoform specific start-loss mutations causing expression loss of a tissue relevant isoform of an essential protein can cause a genetic disease, even when an organism-wide protein absence is incompatible with life. We provide additional examples where a similar disease mechanism applies.

genetics↗

bioRxiv2019

SMN-primed ribosomes modulate the translation of transcripts related to Spinal Muscular Atrophy

The contribution of ribosome heterogeneity and ribosome-associated factors to the molecular control of proteomes in health and disease remains enigmatic. We demonstrate that Survival Motor Neuron (SMN) protein, loss of which causes the neuromuscular disease spinal muscular atrophy (SMA), binds to ribosomes and that this interaction is tissue-dependent. SMN-primed ribosomes are positioned within the first five codons of a set of mRNAs which are enriched in IRES-like sequences in the 5UTR and rare codons at the beginning of their coding sequence. Loss of SMN at early-stages of SMA induces translational defects in vivo, characterized by ribosome depletion in rare codons at the third and fifth position of the coding sequence. These positional defects cause ribosome depletion from mRNAs bound by SMN-primed ribosomes and translational impairment of proteins involved in motor neuron function and stability, including acetylcholinesterase. Thus, SMN plays a crucial role in the regulation of ribosome fluxes along mRNAs which encode proteins relevant to SMA pathogenesis.

neuroscience↗

bioRxiv2017

Active ribosome profiling with RiboLace

Ribosome profiling, or Ribo-Seq, is based around large-scale sequencing of RNA fragments protected from nuclease digestion by ribosomes. Thanks to its unique ability to provide positional information concerning ribosomes flowing along transcripts, this method can be used to shed light on mechanistic aspects of translation. However, current Ribo-Seq approaches lack the ability to distinguish between fragments protected by ribosomes in active translation or by inactive ribosomes. To overcome these significant limitation, we developed RiboLace: a novel method based on an original puromycin-containing molecule capable of isolating active ribosomes by means of an antibody-free and tag-free pull-down approach. RiboLace is fast, works reliably with low amounts of input material, and can be easily and rapidly applied both in vitro and in vivo, thereby generating a global snapshot of active ribosome footprints at single nucleotide resolution.

molecular biology↗

bioRxiv2017

In vivo translatome profiling reveals early defects in ribosome biology underlying SMA pathogenesis

BackgroundGenetic alterations impacting on ubiquitously expressed proteins involved in mRNA metabolism often result in neurodegenerative conditions, with increasing evidence suggesting that translational defects can contribute to disease. Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by low levels of SMN protein, whose role in disease pathogenesis remains unclear.\n\nResultsBy determining in parallel the in vivo transcriptome and translatome in SMA mice we identified a robust decrease in translational efficiency, arising during early stages of disease. Translational defects affected translation-related transcripts, were cell autonomous, and were fully rescued after treatment with antisense oligonucleotides to restore SMN levels. Defects in translation were accompanied by a decrease in the number of ribosomes in motor neurons in vivo.\n\nConclusionOur findings suggest that neuronal tissues and cells are particularly sensitive to perturbations in translation during SMA, and identify ribosome biology as an important, yet largely neglected, factor in motor neuron degeneration.

neuroscience↗