Project description:5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are modified versions of cytosine in DNA with roles in regulating gene expression. Using whole genomic DNA from mouse cerebellum, we benchmark 5mC and 5hmC detection by Oxford Nanopore Technologies sequencing against other standard techniques. In addition, we assess the ability of duplex base-calling to study strand asymmetric modification. Nanopore detection of 5mC and 5hmC is accurate relative to compared techniques and opens new means of studying these modifications. Strand asymmetric modification is widespread across the genome but reduced at imprinting control regions and CTCF binding sites in mouse cerebellum. Here we demonstrate the unique ability of nanopore sequencing to improve the resolution and detail of cytosine modification mapping.
Project description:Whole-genome bisulfite sequencing (WGBS) is currently the gold standard for DNA methylation (5-methylcytosine, 5mC) profiling, however the destructive nature of sodium bisulfite results in DNA fragmentation and subsequent biases in sequencing data. Such issues have led to the development of bisulfite-free methods for 5mC detection. Nanopore sequencing is a long read non-destructive approach that directly analyzes DNA and RNA fragments in real time. Recently, computational tools have been developed that enable base-resolution detection of 5mC from Oxford Nanopore sequencing data. In this chapter we provide a detailed protocol for preparation, sequencing, read assembly and analysis of genome-wide 5mC using Nanopore sequencing technologies.
Project description:We identified hankyphage prophages within B. thetaiotaomicron isolates gathered from French hospitals. We extracted genomic DNA from an overnight culture from a single colony of each strain and sequenced them using Nanopore sequencing using the Plasmidsaurus platform. This long-read approach helped the assembly of the phages and determination of the hankyphage ends. We also improved the annotation of the reference hankyphage (hankyphage p00 from P. dorei HM719) using a structural prediction approach and annotated our B. thetaiotaomicron hankyphages using this new annotation. In this project we upload the genomic raw reads of nanopore sequencing of our hankyphage-bearing B. thetaiotaomicron collection (jmh strains) and the processed assembled hankyphages.