Project description:S. meliloti strains with a bi- and monopartite genome configuration were constructed by consecutive Cre/lox-mediated site-specific fusions of the secondary replicons. Beside the correct genomic arrangements, these strains and precursors were tested for variations in the nucleotide sequence. Futher, a marker fequency analysis was performed to test if replication is initiated at all origins and to determine the replication termination regions of the triple replicon fusion molecule. To gain the sequence data for these analyses, respective strains were applied to whole genome sequencing using an Illumina MiSeq-System and Oxford Nanopore (MinION) sequencing technology.
Project description:To identify aberrant splicing isoforms and potential neoantigens, we performed full-length cDNA sequencing of lung adenocarcinoma cell lines using a long-read sequencer MinION. We constructed a comprehensive catalog of aberrant splicing isoforms and detected isoform-specific peptides using proteome analysis.
Project description:These experiments use a barcoded pool of reporter transcripts, each of which encode the same mScarlet-PPIG_LCD fusion protein, but using different degrees of GA-multivalency via codon bias, and containing a different number of constitutive introns. In order to be able to perform experiments using this pool, it was necessary to perform long-read sequencing of the plasmid pool to relate the barcodes in the 3' ends of the reporter to their gene structure. Therefore, we performed long-read sequencing of the plasmid pool (both the original pool used for transfection and the ePB plasmid used for PiggyBac integration). Furthermore, to determine the splicing patterns of the reporter genes, we transfected the plasmid pool into HeLa cells for 16 hours, then performed targeted long-read sequencing of the reporter plasmids via RT-PCR. Note: the Nanopore adapter ligation strategy means that reads can come in either orientation. To determine the gene architectures and barcodes, we used fuzzy string matching. First we matched to various fixed sequences throughout the reporter transcripts to determine the orientation of the read and that the read spanned the full length of the transcript. Then we used the same string matching strategy to detect the presence of the different intronic or exonic sequences - the gene architecture. Then we extracted the associated unique plasmid barcode associated with that gene architecture. Example reporter sequences can be found here: https://benchling.com/faraway/f_/kXCfddtQ-public-reporter-plasmid-maps/ or alternatively, in Supplemental Table 2 of the bioRxiv submission here: https://www.biorxiv.org/content/10.1101/2023.08.21.554177v1.supplementary-material
Project description:Here we describe CapTrap-Seq, an experimental workflow designed to address the problem of reduced transcript end detection by long-read RNA sequencing methods, especially at the 5' ends. We apply CapTrap-Seq to profile transcriptomes of the human heart and brain and we compared the obtained results with other library preparation approaches. CapTrap-Seq is a platform-agnostic method and here tested the method by using 3 different long-read sequencing platforms: MinION (ONT), Sequel (PacBaio) and Sequel II (PacBio).
Project description:We applied direct RNA long read sequencing for characterization of transcripts from constructs inserted into HEK293T mammalian cells with different promoters. Direct RNA sequencing was performed on an Oxford Nanopore GridION device using the Direct Sequencing Kit (SQK-RNA004, date accessed 15 May 2024), MinION RNA flow cell (FLO-MIN00RA), and data pre-processing was performed with MinKNOW (v24.06.10).
Project description:More than 60 human disorders have been linked to unstable expansion of short tandem repeat (STR) tracts. STR length and the extent of DNA methylation is linked to disease pathology and can be mosaic in a cell type-specific manner in several repeat expansion disorders. Mosaic phenomenon have been difficult to study to date due to technical bias intrinsic to repeat sequences and the need for multi-modal measurements at single-allele resolution. Nanopore long-read sequencing accurately measures STR length and DNA methylation in the same single molecule but is cost prohibitive for studies assessing a target locus across multiple experimental conditions or patient samples. Here, we describe MASTR-seq, Multiplexed Analysis of Short Tandem Repeats, for cost-effective, high-throughput, accurate, multi-modal measurements of DNA methylation and STR genotype at single-allele resolution. MASTR-seq couples long-read sequencing, Cas9-mediated target enrichment, and PCR-free multiplexed barcoding to achieve a >ten-fold increase in on-target read mapping for 8-12 pooled samples in a single MinION flow cell. We provide a detailed experimental protocol and computational tools and present evidence that MASTR-seq quantifies tract length and DNA methylation status for CGG and CAG STR loci in normal-length and mutation-length human cell lines. The MASTR-seq protocol takes approximately eight days for experiments and one additional day for data processing and analyses.
Project description:In this work, we generated a MHCC97H proteome datasets by In-gel digestion on Orbitrap Fusion Lumos. We systematically compared RNC-seq and Ribo-seq in the context of proteome identification, especially when identifying protein isoforms from AS. We also demonstrated that the single-molecule long read sequencing technique identified thousands of new splice variants and guided the MS identifications of new protein isoforms.