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Olguin-Nava, M.

Publications and source records attributed to Olguin-Nava, M..

2 recordsLinked to original sources

Demultiplexing and barcode-specific adaptive sampling for nanopore direct RNA sequencing

Nanopore direct RNA sequencing (dRNA-seq) enables unique insights into (epi-)transcriptomics. However, applications are currently limited by the lack of accurate and cost-effective sample multiplexing. We introduce WarpDemuX, an ultra-fast and highly accurate adapter-barcoding and demultiplexing approach. WarpDemuX enhances speed and accuracy by fast processing of the raw nanopore signal, use of a lightweight machine-learning algorithm and design of optimized barcode sets. We demonstrate its utility by performing a rapid phenotypic profiling of different SARS-CoV-2 viruses, crucial for pandemic prevention and response, through multiplexed sequencing of longitudinal samples on a single flowcell. This identifies systematic differences in transcript abundance and poly(A) tail lengths during infection. Additionally, integrating WarpDemuX into sequencing control software enables real-time enrichment of target molecules through barcode-specific adaptive sampling, which we demonstrate by enriching low abundance viral RNA. In summary, WarpDemuX is a broadly applicable, high-performance, and economical multiplexing solution for nanopore dRNA-seq, facilitating advanced (epi-)transcriptomic research.

bioinformatics↗

Building Blocks of Understanding: Constructing a Reverse Genetics Platform for studying determinants of SARS-CoV-2 replication.

To better understand viral pathogenesis, host-virus interactions, and potential therapeutic interventions, the development of robust reverse genetics systems for SARS-CoV-2 is crucial. Here, we present a reverse genetics platform that enables the efficient manipulation, assembly, and rescue of recombinant SARS-CoV-2. The versatility of our reverse genetics system was demonstrated by generating recombinant SARS-CoV-2 viruses. We used this system to generate N501Y and Y453F spike protein mutants. Characterization studies revealed distinct phenotypic effects, impact on viral fitness, cell binding, and replication kinetics. We also investigated a recently discovered priming site for NSP9, which is postulated to produce a short RNA antisense leader sequence. By introducing the U76G mutation into the 5UTR, we show that this priming site is necessary for the correct production of genomic and subgenomic RNAs, and also for efficient viral replication. In conclusion, our developed reverse genetics system provides a robust and adaptable platform for the efficient generation of recombinant SARS-CoV-2 viruses for their comprehensive characterization. Significance statementIn this study, we present a versatile reverse genetics platform facilitating the efficient manipulation, assembly, and rescue of recombinant SARS-CoV-2. Demonstrating its adaptability, we successfully engineered N501Y and Y453F spike protein mutants, each exhibiting distinct phenotypic effects on viral fitness, cell binding, and replication kinetics. We also investigated a novel negative sense priming site for NSP9, demonstrating a role in RNA production and viral replication. This straightforward reverse genetic system is therefore a powerful tool to generate recombinant viruses for advancing our understanding of SARS-CoV-2 biology.

microbiology↗