Project description:Library preparation for whole genome bisulphite sequencing (WGBS) is challenging due to side effects of the bisulphite treatment, which leads to extensive DNA damage. Recently, a new generation of methods for bisulphite sequencing library preparation have been devised. They are based on initial bisulphite treatment of the DNA, followed by adaptor tagging of single stranded DNA fragments, and enable WGBS using low quantities of input DNA. In this study, we present a novel approach for quick and cost effective WGBS library preparation that is based on splinted adaptor tagging (SPLAT) of bisulphite-converted single-stranded DNA. Moreover, we validate SPLAT against three commercially available WGBS library preparation techniques, two of which are based on bisulphite treatment prior to adaptor tagging and one is a conventional WGBS method.
Project description:Here we present a performance evaluation of three different plate-based scRNA-seq protocols. Two commercially available kits; NEBNext Single Cell/ Low Input RNA Library Prep Kit (NEB), SMART-seq HT kit (Takara), and non-commercially available protocol Genome & transcriptome sequencing (G&T). We evaluated each kit based upon sensitivity, reproducibility, ease of use and price point per cell. This evaluation is specifically relevant for implementation of scRNA-seq in e.g. diagnostics, requiring high sensitivity in regards of gene detection, high reproducibility between samples, minimum hands on time and smooth sample preparation for technicians, as well as keeping a reasonable price point per patient. G&T protocol delivered the highest detection of genes per single cell, at the absolute lowest price point. Takara's kit delivered likewise high gene detection per single cell, and high reproducibility between sample, however at the absolute highest price points. Here we present pros and cons of each protocol, sequencing breast cancer cell line T47D.
Project description:Protein synthesis is dysregulated in many diseases, but we lack a systems-level picture of how signaling molecules and RNA binding proteins interact with the translational machinery, largely due to technological limitations. Here we present riboPLATE-seq, a scalable method for generating paired libraries of ribosome-associated and total mRNA. As an extension of the PLATE-seq protocol, riboPLATE-seq utilizes barcoded primers for pooled library preparation, but additionally leverages rRNA immunoprecipitation on whole polysomes to measure ribosome association (RA). We demonstrate the performance of riboPLATE-seq and its utility in detecting translational alterations induced by inhibition of protein kinases.
Project description:We present a high-throughput and droplet-based bisulfite sequencing library preparation platform. Our protocol allows production of BS library of 2,000-10,000 single cells within 2 days. In addition to validation using mixed cell lines, we also used the technology to profile various cell types in mouse and human brain samples.
Project description:We performed a parallel analysis of commonly used pre- and post-bisulfite WGBS library preparation protocols for their performance and quality of sequencing outputs. Our results show that bisulfite conversion per se generates pronounced sequencing biases, and subsequent fragmentation and amplification steps lead to several-fold overrepresentation of these artefacts. Standard pre-bisulfite library preparation methods lead to a significantly biased genomic sequence representation and a marked overestimation of methylation levels. We have integrated a bias diagnostic tool in the Bismark package and propose that amplification-free and post-bisulfite procedures should become the gold standard for WGBS library preparation.
Project description:In recent years, tagmentation-based library preparation using a hyperactive version of the Tn5 transposase gained more and more popularity. The limited hands-on time, robustness and high efficiency of the method are essential for the processing of next-generation sequencing libraries form little input material like single cells or the processing of hundreds of samples simultaneously. The hyperactive Tn5 is commercially available (Nextera XT DNA library preparation kit), however, high-throughput experiments with hundreds of samples are costly. Here, we present a highly reproducible Tn5 transposase purification strategy via an N-terminal His6-Sumo3 tag and the workflow for the tagmentation-based NGS library preparation. We demonstrate that NGS libraries processed with the in-house produced Tn5 are of the same quality like those processed with the Nextera XT DNA library preparation kit and that the purification of the transposase is reproducible across institutes. Producing the Tn5 transposase in-house allows for customized experimental design and reduces costs of large-scale experiments dramatically. We describe a novel single cell polyadenylation site mapping protocol that benefits from the fact that the in-house produced Tn5 can be loaded with any desired linker oligonucleotide for tagmentation.
Project description:In recent years, tagmentation-based library preparation using a hyperactive version of the Tn5 transposase gained more and more popularity. The limited hands-on time, robustness and high efficiency of the method are essential for the processing of next-generation sequencing libraries from little input material like single cells or the processing of hundreds of samples simultaneously. The hyperactive Tn5 is commercially available (Nextera XT DNA library preparation kit), however, high-throughput experiments with hundreds of samples are costly. Here, we present a highly reproducible Tn5 transposase purification strategy via an N-terminal His6-Sumo3 tag and the workflow for the tagmentation-based NGS library preparation. We demonstrate that NGS libraries processed with the in-house produced Tn5 are of the same quality like those processed with the Nextera XT DNA library preparation kit and that the purification of the transposase is reproducible across institutes. Producing the Tn5 transposase in-house allows for customized experimental design and reduces costs of large-scale experiments dramatically. We describe a novel single cell polyadenylation site mapping protocol that benefits from the fact that the in-house produced Tn5 can be loaded with any desired linker oligonucleotide for tagmentation.
Project description:We optimzed ATAC-seq library preparation for use with Drosophila melanogaster. The protocol addresses factors specific to fruit flies, such as the insect exoskeleton and smaller genome size. The optimized protocol provides guidelines for sample input, nuclei isolation, and enzymatic reaction times. The data included here were generated using our optimized library preparation workflow.
Project description:Major advances have been made to develop an automated universal 384-well plate sample preparation platform with high reproducibility and adaptability for extraction of proteins from cells within a culture plate. An in-solution digest strategy is employed to generate peptides from the extracted proteins for LC-MS analysis in the 384-well plate. Method evaluation utilized HeLa cells cultured in the 384-well plate ranging from 500 – 10,000 cells. Digestion efficiency was excellent in comparison to the commercial digest peptides standard with minimal sample loss while improving sample preparation throughput by 20 – 40 fold. Analysis of six human cell types, which included two primary cell samples identified and quantified approximately 4,000 proteins for each sample in a single LC-MS/MS injection with as little as 100 – 10,000 cells depending on cell type demonstrating universality of the platform. Implementation of the comprehensive 384-well format protocol for processing cells to clean digested peptides enables large-scale biomarker validation and compound screening through proteomic analysis.