Single Molecule, Real-Time (SMRT) Sequencing uses the natural process of DNA replication to sequence long fragments of native DNA. As such, starting with high-quality, high molecular weight (HMW) genomic DNA (gDNA) will result in better sequencing performance across difficult to sequence regions of the genome. To obtain the highest quality, long DNA it is important to start with sample types compatible with HMW DNA extraction methods. This technical note is intended to give general guidance on sample collection, preparation, and storage across a range of commonly encountered sample types used for SMRT Sequencing whole genome projects. It is important to…
With Single Molecule, Real-Time (SMRT) Sequencing and the Sequel Systems, you can affordably assemble reference-quality microbial genomes that are >99.999% (Q50) accurate.
Brett Hannigan, Computational Biology Project Leader at DNAnexus, demonstrates a fast, accurate, and cost-efficient solution for diploid-aware de novo genome assembly utilizing FALCON on the DNAnexus platform.
This tutorial provides an overview of the Hierarchical Genome Assembly Process (HGAP4) de novo assembly analysis application. HGAP4 generates accurate de novo assemblies using only PacBio data. HGAP4 is suitable for assembling a wide range of genome sizes and complexity. HGAP4 now includes some support for diploid-aware assembly. This tutorial covers features of SMRT Link v5.0.0.
In this webinar, Emily Hatas of PacBio shares information about the applications and benefits of SMRT Sequencing in plant and animal biology, agriculture, and industrial research fields. This session contains an overview of several applications: whole-genome sequencing for de novo assembly; transcript isoform sequencing (Iso-Seq) method for genome annotation; targeted sequencing solutions; and metagenomics and microbial interactions. High-level workflows and best practices are discussed for key applications.
The goal of this session is to help users complete their PacBio genome assembly and generate the best resource for their research. Kingan begins with a brief review of the diploid assembly process used by FALCON and FALCON-Unzip, highlighting the enhanced phasing of the Unzip module, and concluding with recommendations for genome polishing. Next, she explores how heterozygosity can influence the assembly process and how read coverage depth along the assembly can reveal important characteristics of assembly structure. Kingan then recommends approaches, including specific tools, that can be used to quality filter and curate the assembly, including annotation-, coverage-, and…
In this PacBio User Group Meeting presentation, PacBio scientist Kristin Mars speaks about recent updates, such as the single-day library prep that’s now possible with the Iso-Seq Express workflow. She also notes that one SMRT Cell 8M is sufficient for most Iso-Seq experiments for whole transcriptome sequencing at an affordable price.
Jana U’Ren of the University of Arizona discusses the fungi that live inside of plants at a PacBio workshop at the PAG 2020 conference. U’Ren studies the biology and evolution of mycorrhizal fungi found in the photosynthetic tissue of plant leaves, which are grouped together functionally as endophytes. In this video, she shares some of her preliminary findings collecting and analyzing samples from Boreal forests around the world.
Mark Blaxter, project lead of the Sanger Institute’s Darwin Tree of Life, shared an update of the ambitious effort to sequence all 60,000 species believed to be on the British Isles over the next 12 years in this presentation at the PAG 2020 Conference. The Sanger team has already generated data for 94 species, including 44 new moth and butterfly (Lepidoptera) PacBio assemblies, which Blaxter describes in this presentation.
PacBio SMRT Sequencing has the unique ability to directly detect base modifications in addition to the nucleotide sequence of DNA. Because eukaryotes use base modifications to regulate gene expression, the absence or presence of epigenetic events relative to the location of genes is critical to elucidate the function of the modification. Therefore an integrated approach that combines multiple omic-scale assays is necessary to study complex organisms. Here, we present an integrated analysis of three sequencing experiments: 1) DNA sequencing, 2) base-modification detection, and 3) Iso-seq analysis, in Neurospora crassa, a filamentous fungus that has been used to make many landmark…
Single Molecule Real-Time (SMRT) DNA sequencing provides a wealth of kinetic information beyond the extraction of the primary DNA sequence, and this kinetic information can provide for the direct detection of modified bases present in genomic DNA. This method has been demonstrated for base modification detection in prokaryotes at base and strand resolutions. In eukaryotes, the common base modifications known to exist are the cytosine variants including methyl, hydroxymethyl, formyl and carboxyl forms. Each of these modifications exhibits different signatures in SMRT kinetic data, allowing for unprecedented possibilities to differentiate between them in direct sequencing data. We present early results…
PacBio sequencing holds promise for addressing large-genome complexities, such as long, highly repetitive, low-complexity regions and duplication events that are difficult to resolve with short-read technologies. Several strategies, with varying outcomes, are available for de novo sequencing and assembling of larger genomes. Using a diploid fungal genome, estimated to be ~80 Mb in size, as the basis dataset for comparison, we highlight assembly options when using only PacBio sequencing or a combined strategy leveraging data sets from multiple sequencing technologies. Data generated from SMRT Sequencing was subjected to assembly using different large-genome assemblers, and comparisons of the results will be…
SFAF 2014 Presentation Slides: James Gurtowski of Cold Spring Harbor Laboratory (CSHL) shared assembly results for a variety of eukaryotic genomes, including yeast, arabidopsis, and rice.
Since the advent of Next-Generation Sequencing (NGS), the cost of de novo genome sequencing and assembly have dropped precipitately, which has spurred interest in genome sequencing overall. Unfortunately the contiguity of the NGS assembled sequences, as well as the accuracy of these assemblies have suffered. Additionally, most NGS de novo assemblies leave large portions of genomes unresolved, and repetitive regions are often collapsed. When compared to the reference quality genome sequences produced before the NGS era, the new sequences are highly fragmented and often prove to be difficult to properly annotate. In some cases the contiguous portions are smaller than…
PacBio 2015 User Group Meeting Presentation Slides: Ken Naito of the NIAS Genetic Resource Center presented on whole genome sequencing of the azuki bean (Vigna angularis). Using single molecule real-time (SMRT) sequencing technology, they achieved the best contiguity and coverage among currently assembled legume crops.