Biology subjects

Naarmann-de Vries, I.

Publications and source records attributed to Naarmann-de Vries, I..

3 recordsLinked to original sources

bioRxiv2026

WarpDemuX-custom - Multiplexed sequence-specific direct RNA sequencing

Nanopore direct RNA sequencing has emerged as a powerful technology for studying RNA and modifications at single-molecule resolution. Although originally developed for polyadenylated RNAs, protocol adaptations have extended its application to non-polyadenylated RNA species, including tRNAs and rRNAs. However, the lack of open and flexible (de)multiplexing solutions remains a limitation for large-scale sequencing studies. Existing community-driven approaches enable multiplexing of polyadenylated RNAs and, more recently, tRNAs, but do not fully address the challenges of targeted sequence-specific Nanopore sequencing of non-polyadenylated RNAs. Here, we present an improved sequence-specific direct RNA sequencing protocol for ribosomal RNAs, achieving enhanced capture and longer read lengths as demonstrated for human 28S rRNA. We complement this protocol with an expanded WarpDemuX software toolbox for flexible sequence-specific (de)multiplexing. We validate the approach using human cell lines carrying knockouts of different C/D box snoRNAs involved in site-specific 2'-O-ribose methylation of 28S rRNA. Our results demonstrate efficient multiplexed detection of sequence-specific RNA molecules and associated modification changes. While established here using rRNA, we validate our approach on another panel of non-polyadenylated RNA species, providing an open and scalable framework for targeted direct RNA sequencing and RNA modification analysis

bioinformatics↗

bioRxiv2023

mAFiA: Detecting m6A at single-molecular resolution via direct-RNA sequencing

Direct-RNA sequencing offers the possibility to simultaneously identify canonical bases and epi-transcriptomic modifications in each single RNA molecule. Thus far, the development of computational methods has been hampered by the lack of biologically realistic training data that carries modification labels at molecular resolution. Here, we report on the synthesis of such samples and the development of a bespoke algorithm that accurately detects single m6A nucleotides on single molecules in both synthetic RNAs and natural mRNA.

bioinformatics↗

bioRxiv2018

On the optimal design of metabolic RNA labeling experiments.

Massively parallel RNA sequencing (RNA-seq) in combination with metabolic labeling has become the de facto standard approach to study alterations in RNA transcription, processing or decay. Regardless of advances in the experimental protocols and techniques, every experimentalist needs to specify the key aspects of experimental design: For example, which protocol should be used (biochemical separation vs. nucleotide conversion) and what is the optimal labeling time? In this work, we provide approximate answers to these questions using asymptotic theory of optimal design. Specifically, we derive the optimal labeling time for any given degradation rate and show that sub-optimal time points yield better rate estimates if they precede the optimal time point. Subsequently, we show that an increase in sample numbers should be preferred over an increase in sequencing depth. Lastly, we provide some guidance on use cases when laborious biochemical separation outcompetes recent nucleotide conversion based methods (such as SLAMseq).

bioinformatics↗